Beclomethasone dipropionate enemas for treating inflammatory bowel disease without producing Cushing's syndrome or hypothalamic pituitary adrenal suppression

Anti-Inflammatory Potential of Beclometasone-Loaded Filomicelles on Activated Human Monocytes

Polymeric micelles with a hydrophobic core represent versatile nanostructures for encapsulation and delivery of water-insoluble drugs. Here, water-insoluble beclometasone dipropionate (BDP) which is a potent anti-inflammatory therapeutic agent but limited to topical applications so far, is encapsulated. Therefore, this work used an amphiphilic block copolymer self-assembling into flexible polymeric filomicelles, which have recently proven to selectively target inflamed areas in patients with inflammatory bowel disease (IBD). The small diameter and flexibility of these filomicelles is considered beneficial for transepithelial passages, while their length minimizes the unspecific uptake into nontargeted cells. This work successfully establishes a protocol to load the water-insoluble BDP into the core of the filomicelles, while maintaining the particle stability to prevent any premature drug release. The anti-inflammatory efficacy of BDP-loaded filomicelles is further investigated on lipopolysaccharide (LPS) stimulated human monocytes. In these ex vivo assays, the BDP-loaded filomicelles significantly reduce TNF-α, IL-6, IL-1ß, IL-12p70, IL-17a, and IL-23 release after 24 h. Additional time course study of drug-loaded filomicelles and their comparison with a common water-soluble and unspecific corticosteroid demonstrate promising results with significant immune response suppression in stimulated monocytes after 2 and 6 h. These findings demonstrate the potential of polymeric filomicelles as a vehicle for potent water-insoluble corticosteroids.

Efficacy and safety of oral beclomethasone dipropionate and budesonide MMX versus 5-aminosalicylates or placebo in ulcerative colitis: a systematic review and meta-analysis

Background

Low bioavailability steroids, including beclomethasone dipropionate (BDP) and budesonide MMX, have been developed to ensure colonic targeting and low systemic activity than systematic corticosteroids in treating patients with ulcerative colitis (UC).

Objectives

This systematic review and meta-analysis evaluated the efficacy and safety of BDP and budesonide MMX® compared with 5-aminosalicylic acid (5-ASAs) or placebo, in patients with mild-to-moderate UC.

Design

Systematic review and meta-analysis.

Methods

We searched MEDLINE, EMBASE, and the Cochrane central register of controlled trials from inception to December 2021. We included all available randomized controlled trials (RCTs) comparing oral BDP or budesonide MMX with 5-ASAs or with placebo in induction of remission of mild-to-moderate UC. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.

Results

We identified two RCTs comparing BDP 5 mg with 5-ASA, one RCTs comparing BDP 10 mg with 5-ASA, two RCTs BDP 5 mg versus placebo, one RCT BDP 10 mg versus placebo, two RCTs budesonide MMX 9 mg versus 5-ASA, and six RCTs budesonide MMX 9 mg versus placebo. In terms of achieving clinical remission or improvement, BDP 5 mg, BDP 10 mg, and budesonide MMX 9 mg were more effective than placebo (OR 2.36, 95% CI 1.37-4.08; OR 2.23, 95% CI 1.02-4.87; and OR 2.03, 95% CI 1.45-2.85, respectively). The drugs were also more effective than placebo in achieving endoscopic remission. Regarding the comparisons with 5-ASA, we found no differences between 5-ASA and BDP 5 mg or BDP 10 mg or budesonide MMX 9 mg in achieving clinical remission or improvement (OR 0.90, 95% CI 0.51-1.57; OR 1.54, 95% CI 0.42-5.64; and OR 1.17, 95% CI 0.82-1.66). However, 5-ASA was more effective than budesonide MMX 9 mg in achieving histological remission (OR 0.33, 95% CI 0.16-0.70). Overall, all the drugs were safe and well tolerated.

Conclusion

Low bioavailability steroids were more effective than placebo in achieving clinical remission, clinical and endoscopic remission, and histological remission. No differences were found between 5-ASA and BDP or budesonide MMX. Surely, more RCTs, also comparing BDP and budesonide MMX, are mandatory to confirm or not these results.

Glucocorticoid induced adrenal insufficiency

Synthetic glucocorticoids are widely used for their anti-inflammatory and immunosuppressive actions. A possible unwanted effect of glucocorticoid treatment is suppression of the hypothalamic-pituitary-adrenal axis, which can lead to adrenal insufficiency. Factors affecting the risk of glucocorticoid induced adrenal insufficiency (GI-AI) include the duration of glucocorticoid therapy, mode of administration, glucocorticoid dose and potency, concomitant drugs that interfere with glucocorticoid metabolism, and individual susceptibility. Patients with exogenous glucocorticoid use may develop features of Cushing's syndrome and, subsequently, glucocorticoid withdrawal syndrome when the treatment is tapered down. Symptoms of glucocorticoid withdrawal can overlap with those of the underlying disorder, as well as of GI-AI. A careful approach to the glucocorticoid taper and appropriate patient counseling are needed to assure a successful taper. Glucocorticoid therapy should not be completely stopped until recovery of adrenal function is achieved. In this review, we discuss the factors affecting the risk of GI-AI, propose a regimen for the glucocorticoid taper, and make suggestions for assessment of adrenal function recovery. We also describe current gaps in the management of patients with GI-AI and make suggestions for an approach to the glucocorticoid withdrawal syndrome, chronic management of glucocorticoid therapy, and education on GI-AI for patients and providers.

Use of corticosteroids and immunosuppressive drugs in inflammatory bowel disease: Clinical practice guidelines of the Italian Group for the Study of Inflammatory Bowel Disease

The two main forms of intestinal bowel disease, namely ulcerative colitis and Crohn's disease, are not curable but can be controlled by various medical therapies. The Italian Group for the Study of Inflammatory Bowel Disease (IG-IBD) has prepared clinical practice guidelines to help physicians prescribe corticosteroids and immunosuppressive drugs for these patients. The guidelines consider therapies that induce remission in patients with active disease as well as treatment regimens that maintain remission. These guidelines complement already existing guidelines from IG-IBD on the use of biological drugs in patients with inflammatory bowel diseases.

Efficacy and Safety of Oral Beclomethasone Dipropionate in Ulcerative Colitis: A Systematic Review and Meta-Analysis

Background and Aim

We performed a systematic review and meta-analysis of all the available evidence comparing efficacy and safety of oral prolonged released beclomethasone dipropionate (BDP) to active oral controls in patients with mild-to-moderate ulcerative colitis (UC). A subgroup-analysis compared the effectiveness of BDP and 5-ASA.

Methods

Literature research was performed in different databases, as well as manual search to identify abstracts from international meetings with data not included in extensive publications. Experts in the field and companies involved in BDP development and manufacture were contacted to identify unpublished studies used for registration purposes. Dichotomous data were pooled to obtain odds ratio meta-analysis.

Results

Five randomized controlled trials that compared oral BDP 5mg/day vs. all oral active controls in treating UC were identified as eligible. Efficacy and safety have been addressed after 4-week treatment period. One study evaluated efficacy and safety of BDP vs. prednisone and 4 of BDP vs. 5-ASA. Treatment with oral BDP 5 mg/day induces a significant better clinical response compared to oral 5-ASA (OR 1.86, 95% CI = 1.23–2.82, P = 0.003). The effect is detectable even when the comparison to prednisone is added (OR 1.41, 95% CI = 1.03–1.93, P = 0.03). Data on remission indicate that the potential clinical efficacy of BDP may be better than 5-ASA (OR 1.55, 95% CI = 1.00–2.40, P = 0.05). This difference is lost when the comparison with prednisone is added (OR 1.30, 95% CI = 0.76–2.23, P = 0.34). The safety analysis showed no differences between BDP and 5-ASA (OR 0.55, 95% CI = 0.24–1.27, P = 0.16). The lack of difference is maintained even when the study with prednisone is added (OR 0.67, 95% CI = 0.44–1.01, P = 0.06). However, the trend of difference is clear and indicates a more favourable safety profile of BDP compared to 5-ASA and PD.

Conclusions

Oral prolonged release BDP showed a superior efficacy vs. oral 5-ASA in inducing clinical improvement of mild-to-moderate UC with a similar safety profile.

Efficacy and Safety of Beclomethasone Dipropionate versus 5-Aminosalicylic Acid in the Treatment of Ulcerative Colitis: A Systematic Review and Meta-Analysis

Background

Ulcerative colitis (UC) is a chronic and remitting inflammatory disease that is characterized by chronic idiopathic inflammation of the colon and bloody diarrhea. Currently drug treatment is the main intervention for patients with mild to moderate UC. Mesalazine (5-ASA) and beclomethasone dipropionate (BDP) have been widely used for the treatment of UC and have yielded satisfactory results. This study compared the effectiveness of 5-ASA and BDP in the treatment of UC.

Methods

The PubMed, Medline, SinoMed, Embase, and Cochrane Librinary databases were searched for eligible studies. Data were extracted by two of the coauthors independently and were analyzed using RevMan statistical software, version 5.3. Weighted mean differences (WMDs), odds ratios (ORs), and 95% confidence intervals (CIs) were calculated. Cochrane Collaboration’s Risk of Bias Tool was used to assess the risk of bias.

Results

Seven randomized controlled trials that compared BDP with 5-ASA in treating UC were identified as eligible. The methodological quality of the trials ranged from low to moderate. A pooled analysis of effectiveness based on the Disease Activity Index (DAI) or other assessment method after treatment revealed that in the treatment of UC, there are no obvious differences between BDP and 5-ASA in inducing remission and clinical improvement (OR = 0.76, 95% CI = 0.56–1.03, P = 0.08). The total numbers of adverse events associated with BDP and 5-ASA treatments for UC were similar (OR = 1.21, 95% CI = 0.71–2.09, P = 0.48). The safety profiles for these two drugs are good. According to subgroup-analysis, we found no obvious differences of clinical efficacy between BDP and 5-ASA no matter oral or enema administration was used in the treatment of UC. A sensitivity analysis demonstrated the stability of the pooled results.

Conclusion

During induction treatment of mild to moderate UC, there is no obvious difference between the two groups with respect to remission and clinical improvement. Given that the upper confidence limit for the OR barely exceeds 1.0 and that the p-value is close to 0.05 for this primary efficacy outcome as well as that the horizontal block lies to the left of the vertical line, it indicates that the clinical efficacy of BDP may be better than 5-ASA. However, taking into account that BDP has the risk of hypothalamic-pituitary-adrenal axis (HPA) suppression, 5-ASA has a potential advantage of safety in the treatment of mild to moderate UC.

An observational study of the use of beclomethasone dipropionate suppositories in the treatment of lower urinary tract inflammation in men

Background

Nonbacterial prostatitis, together with chronic pelvic pain syndrome, accounts for 90–95 % of prostatitis cases. Anti-inflammatory medications are commonly used to reduce storage/inflammatory symptoms that can deteriorate quality of life. The purpose of this study was to observe the efficacy and safety of beclomethasone dipropionate rectal suppositories (Topster®) in inflammations of the lower urinary tract in men.

Methods

Patients underwent diagnostic and therapeutic protocols according to current evidence-based practice. Efficacy assessments: voiding parameters, perineal pain, International Prostate Symptom Score (IPSS), digital rectal examination (DRE). Adverse events and patient compliance were recorded throughout the study.

Results

One hundred eighty patients were enrolled, mean age 52 ± 14.97. Most frequent diagnosis: nonbacterial prostatitis (85 %). All patients completed visits 1 and 2. All patients were treated with beclomethasone dipropionate (BDP) suppositories, 136/180 also with Serenoa repens (SR) extract. Antibiotics were rarely required.

162/180 patients presented clinically significant improvements and terminated treatment.

Mean change vs. baseline in voiding frequency: −3.55 ± 2.70 n/day in patients taking only BDP and −3.68 ± 2.81 n/day in those taking both BDP and SR (P<.0001 in both groups). Uroflowmetry improved significantly; change from baseline 3.26 ± 5.35 ml/s in BDP only group and 5.61 ± 7.32 ml/s in BDP + SR group (P = 0.0002 for BDP, P<.0001 for BDP + SR). Urine stream normal in 35 % of patients at visit 1 and 57.22 % of patients at visit 2. Mean change in perineal pain, on 0–10 VAS, −0.66 ± 2.24 for BDP only group (P = 0.0699) and −1.37 ± 2.40 for BDP + SR group (P<.0001). IPSS increased at visit 2. No adverse events were reported.

For all parameters, none of the comparisons between groups was found to be statistically significant.

Conclusion

This study confirmed the drug’s good safety profile. We also observed an improvement in the main storage symptoms and clinical findings associated with lower urinary tract inflammation in patients treated with beclomethasone dipropionate suppositories.

Topical agents for idiopathic distal colitis and proctitis

Rectally administered topical agents have demonstrated efficacy in the maintenance of distal colitis (DC) and proctitis and as they are rarely associated with significant blood drug levels, side effects are infrequent. The topical 5-aminosalicylic acid (5-ASA) suppositories and enemas target different regions of the distal colon and are effective for proctitis and DC, respectively. They demonstrate clinical results that are better than oral 5-ASAs and are preferred to topical steroids with better clinical, endoscopic and histological outcomes, without the risk of adrenal suppression. Disease resistant to topical agents, however, can be extremely difficult to manage. The addition of oral 5ASAs, steroids, immunosuppressants and the anti-tumor necrosis factor-α agents may be effective, but can result in significant side effects and not all patients will respond to the therapies. It is for these patients that new and novel therapies are required. Novel topical agents have been proposed for the management of resistant DC. These agents included butyrate, cyclosporine, and nicotine enemas, as well as tacrolimus suppositories, and tacrolimus, ecabet sodium, arsenic, lidocaine, bismuth, rebamipide and thromboxane enemas. While some of these agents appear to demonstrate impressive outcomes, the majority have only been examined in small open-labeled studies. There is thus a desperate need for more randomized double-blinded placebo controlled studies to investigate the clinical utility of these topical therapies. This review summarizes the efficacy of the established topical therapies, and explores the available data on the new and novel topical agents for the management of DC and proctitis.

Drug targeting strategies for the treatment of inflammatory bowel disease: a mechanistic update

The therapeutic management of inflammatory bowel disease (IBD) represents the perfect scenario for drug targeting to the site(s) of action. While existing formulation-based targeting strategies include rectal dosage forms and oral systems that target the colon by pH-, time-, microflora- and pressure-triggered drug release, novel approaches for site-specific delivery in IBD therapy will target the inflamed intestine per se rather than intestinal region. The purpose of this article is to present a mechanistic update on the strategies employed to achieve minimal systemic exposure accompanied by maximal drug levels in the inflamed intestinal tissue. The introduction of biological agents, micro/nanoparticulate carriers including liposomes, transgenic bacteria, and gene therapy opportunities are discussed, as well as the challenges remaining to be achieved in the targeted treatment of IBD.

Meta-analysis: the efficacy of rectal beclomethasone dipropionate vs. 5-aminosalicylic acid in mild to moderate distal ulcerative colitis

BACKGROUND

Beclomethasone dipropionate (BDP) is a second-generation steroid with topical effects and minimal systemic activity for patients with ulcerative colitis (UC).

AIM

To review all available literature to assess the efficacy of enema/foam BDP compared with enema/foam 5-aminosalicylic acid (5-ASA) in the control of left-sided mild-moderate UC.

METHODS

We selected randomized controlled trials of enema/foam BDP compared with enema/foam 5-ASA treatment in patients with UC. Two reviewers assessed trial quality and extracted data independently.

RESULTS

Four trials involving 428 UC patients, 209 treated with 5-ASA (1-4 g o.d.) and 219 with BDP (3 mg o.d.), were included. Intention-to-treat analysis showed that 5-ASA induced improvement/remission of UC in 146 (69.9%) patients, while BDP in 143 (65.3%). The test for heterogeneity (Cochran Q) was not significant and Mantel-Haenszel pooled estimate of odds ratio was 1.23 (95% CI = 0.82-1.85). The results did not change when analysis was performed on a per-protocol basis.

CONCLUSION

The randomized controlled trials identified in this review showed that rectal BDP has equal effect as 5-ASA to control symptoms in UC.

Efficacy and safety of oral beclomethasone dipropionate for ileal or ileal-right colon Crohn's disease of mild-to-moderate activity or in remission: Retrospective study

Although conventional glucocorticosteroids are the main treatments for active Crohn's disease, several problems are associated with steroid dependence and steroid-related adverse events. To assess the efficacy and safety of oral beclomethasone dipropionate (BDP) coated tablets in adults with mild-to-moderate Crohn's disease. Thirty-four patients (age 18-70years) with a diagnosis of Crohn's disease confirmed by conventional criteria (barium enema, clinical criteria, colonoscopy, histology) were retrospectively evaluated in the study. All subjects received a treatment schedule with BDP 5-10mg/day for 24weeks. BDP significantly (p=0.005) reduced mean Crohn's Disease Activity Index (CDAI) score from 169.6 at baseline to 123.2 after 24weeks. Clinical success was evident at 24weeks in 66.7% of patients with initial active disease, and remission was maintained at week 24 in 93.8% of patients with remission at baseline. Overall, female non-smokers had the best response to treatment. BDP was well tolerated and the only adverse events observed were nausea (n=1), facial erythema (n=1) and one patient with raised fasting blood glucose level. These results clearly suggest that oral BDP coated tablets are effective and safe for treatment of mild-to-moderate Crohn's disease of ileal or ileal-right colonic localisation.

Beclomethasone dipropionate versus mesalazine in distal ulcerative colitis: a multicenter, randomized, double-blind study

BACKGROUND

Topical beclomethasone diproprionate has shown efficacy in ulcerative colitis.

AIM

To assess, in a multicenter, randomized, double-blind study, the tolerability and safety of topical beclomethasone diproprionate (3mg) enema and foam versus mesalazine (2g) enema and foam in mild-moderate distal ulcerative colitis.

PATIENTS

In 15 referral gastrointestinal units, 99 patients with distal ulcerative colitis were enrolled. This number was lower than planned according to the statistical analysis, due to a low recruitment rate.

METHODS

Patients were randomly assigned to random preparations (beclomethasone diproprionate enema, beclomethasone diproprionate foam, mesalazine enema, mesalazine foam) once nightly for 8 weeks, with clinical and endoscopical assessment (Disease Activity Index score) at baseline (T0), 4 (T4) and 8 weeks (T8). Results were expressed as median and range (95% confidence interval). The efficacy was assessed by comparing the Disease Activity Index value at T4 and T8 by using the Student's t-test or the Wilcoxon-Mann-Whitney test.

RESULTS

Efficacy was comparable in the beclomethasone diproprionate or mesalazine groups at both T4 and T8 (response at T4: beclomethasone diproprionate 78% [95% confidence interval 0.6-0.8] versus mesalazine 79% [95% confidence interval 0.6-0.8]; T8: beclomethasone diproprionate 84% [95% confidence interval 0.7-0.9] versus mesalazine 90% [95% confidence interval 0.7-1.0]; p=n.s.; remission at T4: beclomethasone diproprionate 24% [95% confidence interval 0.1-0.3] versus mesalazine 28% [95% confidence interval 0.1-0.3]; remission at T8: beclomethasone diproprionate 36% [95% confidence interval 0.2-0.5] versus mesalazine 52% [95% confidence interval 0.3-0.6]; p=n.s.). The Disease Activity Index lowered at T4 and T8 versus T0 in the four groups (T4 versus T0: beclomethasone diproprionate foam Disease Activity Index 2 versus 6 p<0.0001; beclomethasone diproprionate enema 4 versus 6, mesalazine enema 3 versus 6, mesalazine foam 3.5 versus 7, p<0.001 for all three groups; T8 versus T0: p<0.01). The Disease Activity Index lowered at T8 versus T4 in the beclomethasone diproprionate enema and foam (Disease Activity Index: 2 versus 4 and 1 versus 4, respectively; p<0.05) and in the mesalazine enema (Disease Activity Index: 1.5, range 0-4 versus 3, range 0-12; p<0.01), but not in the mesalazine foam group (Disease Activity Index: 1, range 0-9 versus 3.5, range 0-8; p=n.s.). The safety profile was favourable for all groups.

CONCLUSIONS

Beclomethasone diproprionate and mesalazine enema and foam show a comparable tolerability and efficacy in mild active distal ulcerative colitis.

Topical treatment of distal active ulcerative colitis with beclomethasone dipropionate or mesalamine: a single-blind randomized controlled trial

GOALS

Therapy for active ulcerative colitis (UC) usually involves rectal formulations of corticosteroids (CS), which are characterized by the risk of systemic steroid-related adverse effects.

BACKGROUND

To compare the efficacy and safety of the topically acting CS beclomethasone dipropionate (BDP) versus mesalamine (5-ASA) in the treatment of active UC.

STUDY

Patients with mild to moderate distal active UC were randomized to a 6-week treatment with BDP 3 mg enema o.d. or 5-ASA 1 g enema daily in a single-blind, multicenter, parallel-group, controlled study. The primary efficacy variable was the decrease in Disease Activity Index (DAI) score. Safety variables were adrenal function, monitoring of adverse events, vital signs, and laboratory parameters.

RESULTS

A total of 217 patients were enrolled and treated with BDP (n = 111) or 5-ASA (n = 106). A significant decrease in the DAI score (P < 0.05) was observed in both treatment groups, with a clinical remission rate of 36.7% in the BDP group and of 29.2% in the 5-ASA group. Both treatments were well tolerated. No changes from baseline in morning cortisol levels were observed in the BDP group.

CONCLUSIONS

BDP administered as a rectal enema over a 6-week treatment period was efficacious and safe in patients with active UC, without interference with pituitary adrenal axis.

Oral beclometasone dipropionate in the treatment of extensive and left-sided active ulcerative colitis: a multicentre randomised study

AIM

To explore the efficacy and safety of the topically acting steroid beclometasone dipropionate (BDP) in an oral controlled release formulation in the treatment of extensive or left-sided ulcerative colitis.

METHODS

In a multicentre, randomised, parallel-group, single-blind study, patients with active mild to moderate ulcerative colitis were randomised to a 4-week treatment with BDP 5 mg/day o.d. vs. 5-ASA 0.8 g t.d.s. The primary efficacy variable was the decrease of Disease Activity Index (DAI) (clinical symptoms and endoscopic appearance of mucosa). Safety was evaluated by monitoring adverse events, vital signs, haematochemical parameters and adrenal function.

RESULTS

One hundred and seventy-seven patients were enrolled and randomly treated with BDP (n = 90) or 5-ASA (n = 87). Mean DAI score decreased in both treatments groups (P < 0.0001 vs. baseline for both groups). Clinical remission was achieved in 63.0% of patients in the BDP group vs. 62.5% in the 5-ASA group. A significant DAI score improvement (P < 0.05) in favour of BDP was observed in patients with extensive disease. Both treatments were well tolerated. Mean plasma cortisol levels were significantly reduced vs. baseline in BDP recipients, but without signs of pituitary-adrenal function depletion.

CONCLUSION

Oral BDP gave an overall treatment result in patients with active ulcerative colitis without signs of systemic side-effects.

Oral beclometasone dipropionate in the treatment of active ulcerative colitis: a double-blind placebo-controlled study

AIM

To evaluate efficacy and safety of oral beclometasone dipropionate (BDP) when added to 5-ASA in the treatment of patients with active ulcerative colitis.

METHODS

In a 4-week, placebo-controlled, double-blind study, patients with extensive or left-sided mild to moderate active ulcerative colitis were randomized to receive oral 5-ASA (3.2 g/day) plus BDP (5 mg/day) or placebo. Clinical, endoscopic and histologic features, and haematochemical parameters were recorded at baseline and at the end of the study.

RESULTS

One hundred and nineteen patients were enrolled and randomly treated with BDP plus 5-ASA (n = 58) or placebo plus 5-ASA (n = 61). Both treatment groups showed a statistically significant decrease of disease activity index (DAI) and histology score at the end of treatment (P = 0.001, each). DAI score was lower in the BDP group than in the placebo group (P = 0.014), with more patients in clinical remission in the BDP group (58.6% vs. 34.4%, P = 0.008). Serum cortisol levels significantly decreased in BDP group vs. baseline (P = 0.002), but without signs of pituitary-adrenal function depletion. A low incidence of adverse events was observed in both groups.

CONCLUSIONS

Oral BDP in combination with oral 5-ASA is significantly more effective than 5-ASA alone in the treatment of patients with extensive or left-sided active ulcerative colitis.

Comparative tolerability of treatments for inflammatory bowel disease

Despite limited understanding of therapeutic aetiopathogenesis of ulcerative colitis and Crohn's disease, there is a strong evidence base for the efficacy of pharmacological and biological therapies. It is equally important to recognise toxicity of the medical armamentarium for inflammatory bowel disease (IBD). Sulfasalazine consists of sulfapyridine linked to 5-aminosalicylic acid (5-ASA) via an azo bond. Common adverse effects related to sulfapyridine 'intolerance' include headache, nausea, anorexia, and malaise. Other allergic or toxic adverse effects include fever, rash, haemolytic anaemia, hepatitis, pancreatitis, paradoxical worsening of colitis, and reversible sperm abnormalities. The newer 5-ASA agents were developed to deliver the active ingredient of sulfasalazine while minimising adverse effects. Adverse effects are infrequent but may include nausea, dyspepsia and headache. Olsalazine may cause a secretory diarrhoea. Uncommon hypersensitivity reactions, including worsening of colitis, pancreatitis, pericarditis and nephritis, have also been reported. Corticosteroids are commonly prescribed for treatment of moderate to severe IBD. Despite short term efficacy, corticosteroids have numerous adverse effects that preclude their long term use. Adverse effects include acne, fluid retention, fat redistribution, hypertension, hyperglycaemia, psycho-neurological disturbances, cataracts, adrenal suppression, growth failure in children, and osteonecrosis. Newer corticosteroid preparations offer potential for targeted therapy and less corticosteroid-related adverse effects. Azathioprine and mercaptopurine are associated with pancreatitis in 3 to 15% of patients that resolves upon drug cessation. Bone marrow suppression is dose related and may be delayed. The adverse effects of methotrexate include nausea, leucopenia and, rarely, hypersensitivity pneumonia or hepatic fibrosis. Common adverse effects of cyclosporin include nephrotoxicity, hypertension, headache, gingival hyperplasia, hyperkalaemia, paresthesias, and tremors. These adverse effects usually abate with dose reduction or cessation of therapy. Seizures and opportunistic infections have also been reported. Antibacterials are commonly employed as primary therapy for Crohn's disease. Common adverse effects of metronidazole include nausea and a metallic taste. Peripheral neuropathy can occur with prolonged administration. Ciprofloxacin and other antibacterials may be beneficial in those intolerant to metronidazole. Newer immunosuppressive agents previously reserved for transplant recipients are under investigation for IBD. Tacrolimus has an adverse effect profile similar to cyclosporin, and may cause renal insufficiency. Mycophenolate mofetil, a purine synthesis inhibitor, has primarily gastrointestinal adverse effects. Biological agents targeting specific sites in the immunoinflammatory cascade are now available to treat IBD. Infliximab, a chimeric antibody targeting tumour necrosis factor-or has been well tolerated in clinical trials and early postmarketing experience. Additional trials are needed to assess long term adverse effects.

Inflammatory bowel disease

IBD results from the interaction of genetic and environmental factors (e.g., smoking). Clinical suspicion is the key to diagnosis, which then rests on colonoscopy, histopathological examination of multiple biopsy specimens, small bowel barium radiology and faecal examination. The primary goal of treatment is remission--histological in ulcerative colitis and symptomatic in Crohn's disease. Treating active disease and maintaining remission require different approaches. For active disease, short term corticosteroids are the mainstay of treatment, while immunosuppressive drugs are important in chronically active disease. For maintenance, mesalazine-delivering drugs and immunosuppressive agents are efficacious in both ulcerative colitis and Crohn's disease; patients with Crohn's disease should not smoke.

The gastrointestinal passage and release of beclomethasone dipropionate from oral delivery systems in ileostomy volunteers

AIMS

To study the delivery of 15 mg beclomethasone 17,21-dipropionate (BDP) to the distal part of the small bowel for three oral sustained-release formulations (I-III) and a reference capsule in volunteer ileostomists, and to compare these findings with the in vitro dissolution profiles.

METHODS

Two groups of nine ileostomy volunteers (aged 20-61 years), who were otherwise healthy, were enrolled in the study. The recovery of BDP and its metabolite beclomethasone 17-monopropionate (B17P) in ileostomy effluent was investigated in a cross-over study after administration of formulations I or II or a reference capsule containing micronised BDP, and in a second open study after administration of formulation III. Radio-opaque granules were coadministered for evaluation of gastrointestinal passage. Ileostomy effluents were collected hourly for 10-12 h following drug intake. After marker beads had been counted on X-rays, ileostomy collections were analysed for BDP and its metabolites. Cumulative recovery, lag-time and mean transit time were determined for drug and marker beads.

RESULTS

Gastrointestinal passage characteristics were similar for all treatments. Total drug recovery was approximately three times higher for the sustained-release formulations than for the reference capsule. Recovery of B17P from stoma fluid samples was significantly lower for formulation III than for formulations I and II.

CONCLUSIONS

The novel oral formulations delivered substantial amounts of steroid drug at the distal small bowel/proximal colon, which may warrant further studies to evaluate clinical applicability.

Review article: issues in oral administration of locally acting glucocorticosteroids for treatment of inflammatory bowel disease

Inflammatory bowel diseases are treated in some cases by local administration of anti-inflammatory drugs. Local delivery of drugs in the colon following oral administration may lead to improved efficacy/side-effect profiles and may improve patient compliance. This review covers a number of issues important in the design of oral delivery systems of glucocorticosteroids for local therapy of colonic inflammation. The choice of specific glucocorticosteroids is based on the drug's physicochemical and pharmacological properties. The conditions under which an orally administered glucocorticosteroid (or other drug) must be delivered to treat ulcerative colitis are also discussed. These conditions include variations in local pH, transit throughout the gastrointestinal tract, the potential role of gut microflora, and drug dissolution in both the healthy and diseased large intestine. The effective delivery of topically-active glucocorticosteroids in ulcerative colitis and Crohn's colitis patients is complex, but if successful could improve their usefulness.

A practical guide to the management of distal ulcerative colitis

This article reviews the role of corticosteroids, sulfasalazine and mesalazine (5-aminosalicylic acid, mesalamine), immunosuppressive agents and alternative novel drugs for the treatment of distal ulcerative colitis. Short cycles of traditional, rectally administered corticosteroids (methylprednisolone, betamethasone, hydrocortisone) are effective for the treatment of mild to moderately active distal ulcerative colitis. In this context, their systemic administration is limited to patients who are refractory to either oral 5-amino-salicylates, topical mesalazine or topical corticosteroids. Of no value in maintaining remission, the long term use of either or topical corticosteroids may be hazardous. A new class of topically acting corticosteroids [budesonide, fluticasone, beclomethasone dipropionate, prednisolone-21-methasulphobenzoate, tixocortol (tixocortol pivalate)] represents a valid alternative for the treatment of active ulcerative colitis, and may be useful in the treatment of refractory distal ulcerative colitis. Although there is controversy concerning dosage or duration of therapy, oral and topical mesalazine is effective in the treatment of mild to moderately active distal ulcerative colitis. Sulfasalazine and mesalazine remain the first-choice drugs for the maintenance therapy of distal ulcerative colitis. Evidence exists showing a trend to a higher remission rate with higher doses of oral mesalazine. Topical mesalazine (suppositories or enemas) also is effective in maintenance treatment. For patients with chronically active or corticosteroid-dependent disease, azathioprine and mercaptopurine are effective in reducing either the need for corticosteroids or clinical relapses. Moreover, they are effective for long term maintenance remission. Cyclosporin may be useful in inducing remission in patients with acutely severe disease who do not achieve remission with an intensive intravenous regimen. Existing data suggest that azathioprine and mercaptopurine may be effective in prolonging remission in these patients. The role of alternative drugs for the treatment of distal ulcerative colitis and its different forms is reviewed. In particular data are reported concerning the effectiveness of 5-lipoxygenase inhibitors, topical use of short chain fatty acids, nicotine, local anaesthetics, bismuth subsalicylate enema, sucralfate, clonidine, free radical scavengers, heparin and hydroxychloroquine.

Beclomethasone dipropionate enemas versus prednisolone sodium phosphate enemas in the treatment of distal ulcerative colitis

AIM

To compare beclomethasone dipropionate 3 mg/60 mL enema (BDP) and prednisolone sodium phosphate 30 mg/60 mL enema (PP) once daily in patients with active distal ulcerative colitis.

METHODS

One hundred and fifty-seven patients were enrolled in a multicentre, 4-week, randomized, double-blind trial. Patients were assessed at baseline, 2 and 4 weeks.

RESULTS

Both treatment groups showed statistically significant improvement of clinical activity after 2 and 4 weeks. Endoscopy and biopsy showed a reduction in the activity score at the end of the treatment period in both groups. No statistically significant difference was observed between the two treatment groups. After 4 weeks, 29% of patients in the BDP group and 25% in the PP group were considered to be in clinical remission; an improvement was observed in 40% of patients on BDP and in 47% on PP. Mean morning plasma cortisol levels showed a slight but significant reduction in the PP group, while the ACTH test showed that neither drug interfered with the hypothalamic-pituitary-adrenal (HPA) axis function. No significant changes were observed in the laboratory tests. Finally, there was a low incidence of adverse events in both groups.

CONCLUSIONS

It is concluded that, in the topical treatment of active distal ulcerative colitis, BDP 3 mg enemas are as efficacious as PP 30 mg enemas, without interference with the HPA axis.

Colonic delivery of dexamethasone: a pharmacoscintigraphic evaluation

BACKGROUND

Colonic delivery of corticosteroids may reduce the side-effects commonly associated with their use. Therefore, we tested the ability of the naturally occurring polysaccharide guar gum to deliver a corticosteroid, dexamethasone, to the colon using pharmacoscintigraphy. Guar gum is metabolized in the colon by resident bacterial enzymes to trigger drug release.

MATERIALS

Each subject (eight per group, parallel study design) was administered one of four dexamethasone (9 mg) tablet formulations, radiolabelled with 153Sm using neutron activation, under fasted conditions. One formulation was designed to release drug rapidly following ingestion while the other three formulations were designed to delay release of dexamethasone to varying degrees. Progression of the formulations down the gastrointestinal tract was followed by gamma scintigraphy. Serum concentrations were measured over time to relate disintegration profiles of the tablets with pharmacokinetic observations.

RESULTS

The immediate release formulation disintegrated in the stomach, on average, within 20 min of dosing. One of the three delayed release preparations (CD1) began to disintegrate in the small intestine 1.7 +/- 1.0 h after dosing. The second and third delayed release preparations (CD2 and CD3) did not begin to disintegrate until 5.8 +/- 2.3 and 3.6 +/- 1.6 h after dosing, respectively. All three colonic delivery preparations completely disintegrated in the colon ranging from 7.8 +/- 2.7 h (CD1) to 12.4 +/- 3.2 h (CD2) following oral administration. Pharmacoscintigraphic data indicated that 72-82% of the dexamethasone was delivered into the colon although not all the dexamethasone delivered into the colon was absorbed.

CONCLUSIONS

Simple guar gum formulations are capable of delivering the corticosteroid dexamethasone to the colon of normal subjects. Locally delivered corticosteroids may be useful in the treatment of ulcerative colitis and Crohn's disease. Pharmacoscintigraphic evaluation is a useful method to discriminate between the in vivo behaviour of colonic delivery systems.

Review article: topical corticosteroids in inflammatory bowel disease

It would be ideal to treat inflammatory bowel disease with topical corticosteroids that are either not absorbed through the mucosa, or have a substantial first-pass hepatic metabolism. The topical use of hydrocortisone, prednisolone-21-phosphate or betamethasone is often associated with systemic side-effects. Newer corticosteroid preparations (prednisolone metasulphobenzoate, tixocortol pivalate, fluticasone propionate, beclomethasone dipropionate and budesonide) are usually associated with minimal systemic corticosteroid activity. This article reviews the clinical activity and safety of these newer preparations.

New therapeutic agents in the treatment of inflammatory bowel disease

Despite intense investigation, the etiology of inflammatory bowel disease (IBD) remains unknown. Recent studies with new therapeutic agents provide insight into the pathogenesis of IBD through analysis of the clinical response to pharmacologic agents whose mechanism of action is understood. Until new agents are established, IBD will be treated with conventional drugs directed toward modifying the inflammatory responses responsible for gastrointestinal mucosal damage. Sulfasalazine, mesalamine (5-aminosalicylic acid), and corticosteroids will continue to be the mainstay of therapy for the foreseeable future. Antibiotics such as metronidazole and immunosuppressants such as 6-mercaptopurine and methotrexate are useful in Crohn's disease and ulcerative colitis in selected cases. Many new exciting agents are being investigated and show encouraging results in the treatment of IBD. This article reviews the agents used in IBD with an emphasis on new therapeutic agents.

Drug therapy for inflammatory bowel disease: Part I

In a two-part series, recent improvements in drug therapy for inflammatory bowel disease are reviewed. Part I summarizes aminosalicylates and corticosteroids. The active moiety of sulfasalazine, which is 5-aminosalicylic acid (mesalamine), in topical or oral form is as effective as sulfasalazine for treatment and prophylaxis of ulcerative colitis and is tolerated by 80% of sulfasalazine-intolerant patients. Coated forms of mesalamine have a potential advantage in the treatment of Crohn's ileitis in that these forms do not require bacterial cleavage for activity. New rapidly metabolized corticosteroids (budesonide, tixocortol pivalate, beclomethasone dipropionate) in topical and oral forms are emerging as equivalent therapy to standard corticosteroids but are associated with less adrenal suppression.

A steroid enema, budesonide, lacking systemic effects for the treatment of distal ulcerative colitis or proctitis

The aim of this study was to evaluate whether budesonide enema (2 mg/100 ml) had a significantly better effect than placebo in the treatment of distal ulcerative colitis or proctitis. The trial was of controlled, randomized, double-blind design and included 41 treated patients. The treatment time was 4 weeks, with revisits after 2 and 4 weeks. If no improvement was seen, the patient could be switched over to open-label therapy with budesonide enema. Sigmoidoscopy, histology, blood chemistry, and diary cards were used for estimating the effect of treatment. The results showed that budesonide was superior to placebo. Sigmoidoscopy and biopsy scores improved significantly (p less than 0.01) in budesonide-treated patients compared with placebo. Significantly more patients switched over to open budesonide treatment in the placebo group owing to lack of efficacy compared with budesonide (p less than 0.001). No drug-related adverse experiences occurred, and there was no decrease in endogenous morning plasma cortisol levels. It is concluded that budesonide enema appears to be an effective and safe treatment for distal ulcerative colitis and proctitis.

Risk-benefit assessment of drugs used in the treatment of inflammatory bowel disease

Although the aetiology of inflammatory bowel disease remains elusive, many agents are available for the control of symptoms and inflammation. Knowledge of drug pharmacology, indications and side effects is essential to ensure the best possible clinical care while minimising toxicity and inappropriate use. Sulfasalazine consists of sulfapyridine linked to mesalazine (5-aminosalicylic acid) via an azobond. Its use is indicated in the treatment of mild to moderately active ulcerative colitis and in the prevention of relapse in patients with quiescent disease. Patients with mild to moderate colonic or ileocolonic Crohn's disease also benefit from this drug, as do a proportion of patients with isolated small bowel disease. Sulfasalazine has not been uniformly effective in preventing relapse in Crohn's disease, although many clinicians continue its use in patients who respond initially. A high incidence of side effects which limit therapy include intolerance, hypersensitivity reactions and impairment of male infertility. The newer aminosalicylates offer targeted delivery of mesalazine to the bowel, with fewer side effects. Topical mesalazine has proved extremely effective in patients with distal ulcerative colitis; oral forms are effective in the treatment of mild to moderately active ulcerative colitis and in relapse. Both types appear to be effective in the treatment of Crohn's disease, and possibly in preventing relapse. There is no current clinical advantage of one mesalazine preparation over another, nor is there an indication for their use in sulfasalazine-treated patients who have satisfactory response without adverse effects. Corticosteroids are indicated for more severe disease activity where the aminosalicylates have limited efficacy-specifically to induce remission in patients with severe or refractory ulcerative colitis or Crohn's disease. They should not be used to maintain disease remission or in the prevention of postoperative recurrence. Topical corticosteroids allow their local use in distal colitis with minimal systemic side effects. Long term use is limited by side effects, many of which are dose related, although alternate-day therapy may lessen the incidence. Immunosuppressive agents are beneficial for the treatment of refractory inflammatory bowel disease unresponsive to other medications, and may also facilitate the withdrawal of steroids in refractory patients. Mercaptopurine has an added benefit in the treatment of Crohn's disease fistulae; the role of cyclosporin in bowel disease has not been established and its use cannot currently be recommended. The potential toxicity of immunosuppressive agents warrants careful consideration of their use by both physician and patient. Metronidazole is indicated for the treatment of mild to moderate Crohn's disease, including perineal disease. Common side effects include peripheral neuropathy and nausea.(ABSTRACT TRUNCATED AT 400 WORDS)

Colon-specific delivery of dexamethasone from a glucoside prodrug in the guinea pig

Dexamethasone-beta-D-glucoside is a potential prodrug for colonic delivery of the antiinflammatory agent, dexamethasone. The ability of this prodrug to deliver dexamethasone selectively to the colon depends not only on its being slowly absorbed from the alimentary canal, but also on its having chemical and enzymatic stability in the stomach and small intestine. Once reaching the large bowel, it should be quantitatively hydrolyzed to release the active agent. The potential of dexamethasone-beta-D-glucoside for colon-specific delivery of dexamethasone is assessed by determining the rates of its hydrolysis down the alimentary canal of the guinea pig, an animal in which an inflammatory bowel disease model has been developed. The hydrolytic activity is examined in tissues and luminal contents of the stomach, proximal and distal segments of the small intestine, cecum, and colon. For the tissues, the greatest hydrolytic activity is in the proximal small intestine, while the stomach, cecum, and colon have only moderate activity. In contrast, the contents of the cecum and colon show greater activity than the contents of the small intestine and stomach. The luminal contents retained beta-glucosidase activity even after repeated centrifugation and resuspension in a buffer. The activity was unaffected by homogenization. These observations suggest that hydrolytic activity is associated with enzymes located on the surface of luminal cells. The movement and hydrolysis of dexamethasone-beta-D-glucoside down the gastrointestinal tract of the guinea pig are also examined. About 20 to 30% of an oral dose appears to reach the cecum. Here the prodrug is rapidly hydrolyzed to the active drug. From intravenous administration of the prodrug and drug, it is apparent that dexamethasone-beta-D-glucoside is poorly absorbed in the gastrointestinal tract (bioavailability, less than 1%). There is a ninefold selective advantage for delivery of dexamethasone in cecal tissues in the guinea pig under the conditions of this experiment. Thus, there is a potential for a decrease in the usual dose and a concomitant reduction in the systemic exposure to dexamethasone. Because humans have much less glucosidase activity in the small intestine, even greater site-selective delivery to the cecum and colon is expected.

Immunosuppressive drugs in inflammatory bowel disease. A review of their mechanisms of efficacy and place in therapy

Immune effector mechanisms are central to the disease process in inflammatory bowel disease, but it is not clear whether the mucosal or systemic immunological abnormalities are primary phenomena, or are secondary to disease activity. Corticosteroid drugs remain the most effective treatment for active disease, but there is no evidence that they are useful for maintenance therapy. Some patients, however, are dependent on low-dose corticosteroids, and relapse when the drug is withdrawn. These drugs have widespread actions on the immune response, and monocytes are particularly sensitive to corticosteroids. In contrast, sulphasalazine and 5-aminosalicylic acid are effective in maintenance therapy, but do not act primarily by immunosuppressive mechanisms. They are effective in maintenance therapy of ulcerative colitis, and mild relapses of ulcerative colitis and colonic Crohn's disease. New preparations of 5-aminosalicylic acid have reduced side effects, many of which are due to sulphapyridine. Azathioprine and 6-mercaptopurine are used less widely: in Crohn's disease there is reasonable evidence for benefit in chronic active disease unresponsive to corticosteroids, and maintenance of remission. In ulcerative colitis, the position is less clearcut. Overall, trials favour an effect in chronic active disease, and there are pointers to an effect in maintenance of remission. Because of their side effects, in particular marrow suppression, these drugs should be reserved for second-line therapy. Similarly, other cytotoxic drugs are not used because of their side effects. More recently, cyclosporin A, with its selective action on interleukin-2 release and/or synthesis, and inhibition of helper T cell function, has been shown to be helpful in Crohn's disease. At present it should only be used in controlled trials, for patients with unresponsive disease in whom surgery is contraindicated. Renal toxicity may limit long term use. There is little data for cyclosporin A in ulcerative colitis. On the basis that there may be an underlying immune defect in Crohn's disease leading to mucosal inflammation, immunostimulant therapy has been used, but there is no evidence for benefit from treatment with BCG or levamisole in active disease or in maintenance therapy. 7S-Immunoglobulin, plasmapheresis or T-lymphocyte apheresis have been used in acute relapse, but evidence is anecdotal, and does not support their use except as a desperate measure to avoid surgery. Further well-designed controlled trials are needed to define the role of all these drugs, and further research into the mechanism of action on the immune response may shed light on the pathogenesis of inflammatory bowel disease.

Formulation and stability of a beclomethasone dipropionate enema

A beclomethasone dipropionate (BDP) enema and a BDP/mesalazine combination enema (containing 2 mg BDP and 1 g mesalazine and 2 mg BDP, respectively per 40 ml) were formulated. BDP and mesalazine were suspended in a carbomer-water gel. No degradation of BDP was measured during the storage period of the BDP enema (4 weeks at 20 degrees C) and of the BDP/mesalazine enema (44 days at 4 degrees C, 20 degrees C and 37 degrees C, respectively). Progressive darkening of colour occurred for the BDP/mesalazine enema during storage at 20 degrees C and at 37 degrees C, probably induced by mesalazine degradation products. Only very slight colouring was observed at 4 degrees C. Hardly any precipitation of BDP and mesalazine was seen during the storage period and the enemas could easily be resuspended.

A controlled randomized trial of budesonide versus prednisolone retention enemas in active distal ulcerative colitis

Sixty-four patients with active distal ulcerative colitis participated in a multicentre, randomized, investigator-blind trial to compare the effect of budesonide enema, 2 mg/100 ml, with prednisolone disodium phosphate enema, 31.25 mg/100 ml. Budesonide is a new potent corticosteroid with a rapid first-pass elimination. The patients were treated for 4 weeks, and the efficacy of the drugs were evaluated by sigmoidoscopy, histology, and subjective symptoms after 2 and 4 weeks. After 4 weeks of treatment 16 of 31 patients (52%) receiving budesonide enema had healed endoscopically, compared with 8 of 33 (24%) (p = 0.045) receiving prednisolone enema. Budesonide was superior to prednisolone in terms of both significantly improved sigmoidoscopic and histologic scores and subjective symptoms evaluated by visual analogue scales. The patients receiving prednisolone had a significant depression of endogenous cortisol levels during the treatment period, but not the patients receiving budesonide. Budesonide enema seems to be a promising therapy for active distal ulcerative colitis and causes no adverse reactions.

Coating of oral beclomethasone dipropionate capsules with cellulose acetate phthalate enhances delivery of topically active antiinflammatory drug to the terminal ileum

Selective delivery of orally administered topically active antiinflammatory drugs to the terminal ileum and ascending colon could be potentially useful for patients with inflammatory bowel disease involving these sites. Because topical beclomethasone dipropionate (BDP) enemas have been used successfully in the treatment of distal idiopathic colitis, oral formulations of this drug were studied. Enteric-coated or uncoated capsules containing BDP were administered in a single-dose protocol on separate days to 6 healthy volunteers with postcolectomy ileostomies. Ileostomy effluent was collected for a minimum of 8 h and analyzed by high-performance liquid chromatography for BDP, its pharmacologically active derivative beclomethasone monopropionate (BMP), and inactive beclomethasone alcohol. Cellulose acetate phthalate coating of oral BDP capsules significantly increased the mean percentage recovery of BDP + BMP in ileal effluent (43.0% +/- 24.1%) compared to uncoated BDP capsules (13.5% +/- 8.5%, p less than 0.05, Student's paired t-test). We conclude that oral cellulose acetate phthalate-coated BDP capsules may merit clinical trial in Crohn's ileitis and ileocolitis or in conjunction with BDP enemas for topical treatment of ulcerative colitis involving the whole colon.

Treatment of distal ulcerative colitis with beclomethasone enemas: high therapeutic efficacy without endocrine side effects. A prospective, randomized, double-blind trial

Sixteen patients with 18 attacks of distal ulcerative colitis were treated randomly with either 0.5 mg topically administered beclomethasone dipropionate (BDP) or 5 mg betamethasone phosphate (BMT). The effect of the steroid enemas on adrenocortical function was examined by ACTH tests, which were performed before and 20 days after treatment. At completion of the trial, a marked suppression of the adrenocortical function was found in seven of eight patients treated for nine attacks with BMT but not in any patients in the BDP group (P less than 0.01). The mean posttreatment basal and stimulated plasma cortisol levels in the BMT group were significantly lower as compared with the BDP group. The overall therapeutic response assessed by score systems was comparable in the two treatment groups. It is concluded that, in the topical treatment of ulcerative colitis, BDP is preferable to BMT because it exerts an equal anti-inflammatory action without affecting adrenocortical function.

Drug therapy of inflammatory bowel disease

Although the etiology of inflammatory bowel disease is unknown and specific therapy is unavailable, enough information on existing empiric agents is available to allow rational therapy. These agents include sulfasalazine, steroids, immunosuppressive drugs, metronidazole and cholestyramine. Sulfasalazine is a two-part molecule that depends on bacterial cleavage in the colon to deliver locally acting 5-aminosalicylate, whose mechanism of action may relate to inhibition of prostaglandin synthesis. The other half of the molecule, sulfapyridine, is responsible for most of the side effects of the drug. While the efficacy of sulfasalazine in the treatment and prevention of attacks of ulcerative colitis is well established, its use in Crohn's disease appears to be limited to patients with active colitis and ileo-colitis. Sulfasalazine is of major benefit in preventing relapses in patients with ulcerative colitis in remission. New formulations of 5-aminosalicylate may allow delivery of the apparently active moiety to the small bowel and colon without concomitant sulfapyridine toxicity. Corticosteroids are highly effective in acute attacks of ulcerative colitis and Crohn's ileitis and ileo-colitis; the mechanism of antiinflammatory action remains speculative. However, maintenance therapy with steroids is ineffective in preventing relapses or recurrent attacks of either ulcerative colitis or Crohn's disease. Steroid enemas allow topical administration to patients with distal colitis and proctitis with few systemic side effects. In children with growth failure associated with active Crohn's disease, amelioration by steroid therapy may actually restore normal growth. Immunosuppressive agents such as azathioprine and 6-mercaptopurine are of little value in active Crohn's disease when administered alone; however, in combination with other agents they may help diminish steroid dose, close fistulae and prevent relapse. Their mode of action likely depends on long-term cytostatic effects on immune effector cells. Concern for leukopenia and the development of late malignancy has limited their use to patients not responding to other therapies. Metronidazole, an antimicrobial agent that is effective against anaerobes, has recently been shown useful in Crohn's disease involving the colon and perianal area. Its mechanism of action is uncertain, but may be related to its antibacterial actions on anaerobes. Cholestyramine can be successfully used to control bile salt-induced diarrhea in Crohn's patients with terminal ileal resections. Effective drug therapy of inflammatory bowel disease is only part of a total program of management including reassurance, frequent explanation, well-timed use of surgery, and an understanding physician.