Evaluation of topical application of clobetasol 17-propionate from various cream bases

The effect of clobetasol 17-propionate (CP), a potent corticosteroid, in various cream bases on the permeation through artificial membrane was sought. Four formulations were then chosen for a further in vivo skin blanching assay. After calculation of the relationship between in vivo flux0-8 hr determined from a surface recovery technique and in vitro release rate0-8 hr of CP from various formulations, a high correlation coefficient of 0.9996 was achieved. Therefore, the in vitro release study could be used as an index to predict and evaluate the in vivo penetration capacity of CP cream to screen the effective formulation preclinically. After a series of in vivo investigations in this study, it was concluded that myristic acid-added formulations may show a bioequivalence with commercial Dermovate. Furthermore, the flux calculated from the surface recovery technique and delta E detected from the skin blanching assay may be useful as parameters evaluating the quality and effectiveness of CP cream.

A method to measure the solubility of drugs in ointment bases

The solubility of a drug in an ointment base is an important factor determining the efficacy of the formulation. However, it is difficult to measure the solubility of drugs in ointment bases. Thus, a rapid and simple method to determine the solubility of drugs in ointment bases was investigated. Using oxybenzone as a model drug, the bleeding liquid which leaked out from various ointments was collected, and the drug concentration in the bleeding liquid was measured. The drug concentrations in the bleeding liquid collected from soluble type ointments in which the drug is dissolved in bases were in accord with that in the ointments. On the other hand, the drug concentrations in the bleeding liquid collected from crystal dispersion type ointments in which drug crystal are dispersed in bases were the same in spite of the variance in total drug concentrations in the ointments. It was confirmed by microscopic examination that crystals do not flow out into bleeding liquid in the crystal dispersion type ointment. It was also confirmed that the solubility of the drug obtained in the present study was in a solubility range consistent with microscopic examination. Furthermore, an increase in the drug solubility was detected by this method when the drug solubility in the base was raised by adding a detergent into the base. And the results from this method were in accord with the results from microscopic examination. These results suggest that the drug concentration in bleeding liquid represents the solubility of the drug in an ointment.

In vitro properties of ciprofloxacin suppositories formulated with glycerogelatin and theobroma oil bases

Ciprofloxacin suppositories formulated with glycerogelatin approximately nd theobroma oil bases were evaluated for in vitro bioavailability in 0.01N sodium hydroxide (pH approximately 10) and in phosphate buffer (pE- approximately 7.8). The release of ciprofloxacin from the two bases under conditions which simulated the conditions in the rectum was assessed using isolated pig rectum. The release of ciprofloxacin was faster from theobroma oil base than from glycerogelatin base using 0.01N sodium hydroxide as the dissolution medium. The cumulative amount of ciprofloxacin released was markedly reduced from each of the two bases in the presence of isolated pig's rectum and in phosphate buffer.

[Preliminay studies on polyvinyl alcohol gel and its transderman therapeutic system]

By pouring-cooling method, five kinds of hydrophilic gels (starch, agar, gelatin, CMC-Na and PVA) were prepared. The characteristics of preparation, tenacity and elasticiey were compared. Taking the PVA gel which features better characteristics as the carrier a plaster of verapamine hydrochloride and a traditional Chinese antitussive and expectorant in the form of plaster were prepared. The behavior of drug-releasing in vitro and curative effect were preliminarily studied. The results show that the PVA gel may be a fine carrier for transdermal therapeutic system.

In vitro release of betamethasone dipropionate from petrolatum-based ointments

The purpose of this research was to develop new in vitro methodology for measuring release from petrolatum-based semisolids and to determine whether two ointments, both of which contained betamethasone dipropionate, 0.05%, but with different formulations, could be distinguished by release measurements. Several receptor media were explored to optimize the procedure utilizing Franz-type cells. Analysis was by HPLC. The release slope was 1.5 to 6 times greater from the ointment than the "augmented" ointment (which had greater clinical potency). Release was highest with a receptor consisting of a 5% solution of hexane in acetonitrile. Even so, it was necessary to subject samples of receptor from the augmented ointment to evaporation followed by reconstitution with a smaller volume of mobile phase to bring corticosteroid concentrations up to quantifiable levels. In another series of experiments, the HPLC mobile phase was used as the receptor and a relatively large volume (100 microliters) was injected onto the column. With the second approach, measured concentrations were lower but more reproducible. Quantifiable levels of betamethasone dipropionate were obtained for both formulations beginning from the first data point (at 1 hr), with satisfactory linearity of plots of amount released per unit area of membrane versus the square root of time. Using this methodology, it was possible to distinguish the effect of formulation differences in two ointments containing the same drug in the same concentration.

Percutaneous absorption of ketoprofen. I. In vitro release and percutaneous absorption of ketoprofen from different ointment bases

Ketoprofen (KP) is a potent non-steroidal anti-inflammatory drug which is used for the treatment of rheumatoid arthritis. The oral administration of KP can cause gastric irritation and renal adverse effects. Topical application of the drug can bypass gastrointestinal disturbances and provide relatively consistent drug levels at the site of action. Since the efficacy of an ointment depends on the type of ointment base and the concentration of the drug, four different bases (white petrolatum, cold cream, hydrophilic ointment and Carbopol 940 gel) were used at 1, 3, 5, 7 and 10% concentrations of KP to evaluate the effect of ointment base and concentration. The general rank order of the drug release was found to be: Carbopol gel > hydrophilic ointment > cold cream > white petrolatum. There was a positive correlation between the concentration of KP and release rate for all bases except Carbopol gel. The in vivo percutaneous absorption of KP from different ointment bases at 3% concentration was studied by carrageenan-induced paw edema in mice. The rank order of the percent edema inhibition was as follows: Carbopol gel > or = hydrophilic ointment > cold cream > white petrolatum. There was a good correlation between the in vitro and in vivo results.

[Use of multicomponent ointments on a hydrophilic base in the treatment of suppurative wounds]

The results of experimental and clinical studies on the development of multicomponent ointments on a hydrophilic base for local treatment of wounds at phase I of the inflammatory process have been analyzed. A pronounced therapeutic effect of the use of the remedies suggested (levosin, levomecol, dioxycole, sulphamecole, iodmetroxide) resulting from simultaneous dehydrating, antimicrobial, necrolytic and anesthetic effect, 2-fold shortening of the period of wound treatment and improvement of the results of treatment of the patients with different types of purulent surgical infection were noted.

Fluocinonide in an adhesive base for treatment of oral lichen planus. A double-blind, placebo-controlled clinical study

Patients with symptomatic oral lichen planus frequently require therapy to reduce signs and symptoms. For this purpose, corticosteroids are often applied topically. In a randomized, double-blind, placebo-controlled study, the efficacy of the topical application of 0.025% fluocinonide was evaluated. Forty consecutive patients with oral lichen planus diagnosed on the basis of histopathologic and immunofluorescence findings participated in this study. All patients were followed for 3 to 17 months. No adverse effects were noted during follow-up period. In the group of 20 patients that received the drug, 4 patients (20%) showed a complete remission, and 12 patients (60%) had a good or partial response to topical treatment. In the placebo-group, these figures were 0 and 6 (30%), respectively. The majority of the placebo-group (70%) did not respond at all with regard to signs (Xt2 = 10.4; p = 0.0013) and symptoms (Xt2 = 6.97, p = 0.008). The results from this study suggest that topical application of fluocinonide in an adhesive base is a safe and effective drug to reduce signs and symptoms in oral lichen planus.

The long term stability of mechlorethamine hydrochloride (nitrogen mustard) ointment measured by HPLC

HPLC has been applied to determine the stability of mechlorethamine hydrochloride (nitrogen mustard) formulated as an ointment in white soft paraffin (10 mg drug, 50 g paraffin and 1 mL acetone). A new solubilization technique is described for extraction of the drug from the ointment for HPLC analysis which has an extraction efficiency of 76.1% with a coefficient of variation of 10.4%. Stored at 4 degrees C the drug content of the ointment remained stable for at least 84 days and stored at 37 degrees C the drug content remained stable for at least 40 days. In comparison aqueous solutions of mechlorethamine at the same concentration, fully degraded after 4 days. These data will aid hospital pharmacists decide on a standardized protocol for the controlled usage of the ointment which is both safe and cost-effective.

Orbital and palpebral paraffinoma

Paraffinoma is a well-recognized complication of paraffin injection. We describe a 44-year-old man who had an ethmoidectomy for chronic sinusitis. A communicating fracture of the ethmoid bone into the orbit occurred intraoperatively. The nasal cavity was subsequently packed with gauze containing a petrolatum-based antibiotic ointment. Bilateral, periocular swelling developed 1 week later. Optical and electron microscopic studies revealed a paraffinoma.

[Percutaneous absorption of drug from alpha-olefin oligomer gel bases]

The percutaneous absorption of drug from the alpha-olefin oligomer (alpha-OL) gel base prepared by using palmitate of dextrin (Rheopearl KL) as a gelling agent was investigated by using the abdominal skin of rats in vivo. The 20, 30, 40 and 50 alpha-OLs with average molecular weights of 288, 380, 440 and 535, respectively were used in this study. The flurbiprofen (FP) was selected as a model drug. The percutaneous absorption of FP from the alpha-OL gel base was observed to be influenced by the molecular weight of alpha-OL. The percutaneous absorption profiles of FP from 40 and 50 alpha-OLs gel bases were almost the same. On the other hand, the absorption of FP from 30 alpha-OL gel base was significantly higher than those of 40 and 50 alpha-OLs gel bases. Furthermore, the percutaneous absorption of FP from 20 alpha-OL gel base was observed to be the highest in the test gel bases. In order to establish the reason for the differences in the percutaneous absorption of FP from 20, 30, 40 and 50 alpha-OLs gel bases, the apparent partition ratios of FP between water and four different alpha-OLs were determined as a parameter of the affinity of FP for the vehicle. Consequently, it has become apparent that the partition ratio exerts an influence on the percutaneous absorption of FP from the alpha-OL gel bases.

Topical alpha-interferon ointment with dimethyl sulfoxide in the treatment of recurrent genital herpes simplex

The recent in vivo appearance of acyclovir-resistant strains of herpes simplex virus stresses the need for new therapeutic agents to combat this common virus. Topical interferon preparations may help fill this void. In the present study dimethyl sulfoxide was combined with alpha-interferon in an ointment base to increase percutaneous penetration. In this double-blind, placebo-controlled trial, patients with recurrent genital herpes simplex using the topical alpha-interferon preparation had a more rapid cessation of viral shedding when compared to the placebo group (66% culture negative on day 1 vs. 25% of placebo patients; p less than 0.02). In the 90-day post-treatment period, interferon-treated patients had fewer recurrences than their placebo-treated counterparts (1.18 vs. 2.25). This reduction while not statistically significant was encouraging (p less than 0.10).

Homologous fibronectin enhances healing of excised wounds in rats

In order to evaluate the effects of a topical application of homologous fibronectin on the healing of skin wounds, we made 2 excisional wounds on the back skin of each rat, applied ointment with or without fibronectin purified from citrated homologous plasma, and evaluated the effect according to wound size and microscopic findings. Excised lesions treated with carrier alone, but the difference was significant only in the early phase of wound healing, 2 and 3 days, according to wound size and microscopic changes. A significant decrease in wound size could be found in both groups, treated with ointment containing and not containing fibronectin, between day 4 and 9 when wound contraction was a major contributor to wound closure. Therefore it can be concluded that topical application of fibronectin has a beneficial effect on wound healing during its early phase, but no significant influence on wound contraction.

Determination of ibuprofen in ointments by reversed-phase liquid chromatography

A selective reversed-phase HPLC method for the determination of ibuprofen in different ointment bases is described. Following a simple dilution step, the drug was separated from interfering compounds on an octadecylsilica column protected by a precolumn. A mobile phase of aqueous tetrahydrofuran buffered by phosphate was used. Detection was monitored at 219 nm. After each 10 injections of lipophilic samples, the columns were washed with tetrahydrofuran and n-hexane. Recoveries of ibuprofen from a new pilot preparation spiked to contain 4, 5, and 6% of the drug were 100.4, 100.3, and 99.7%, respectively. The precision at each concentration was less than 0.8%. The analysis of ibuprofen degeneration products showed that the method also provides an indication of the stability of the drug.

[Treatment of patients with thermal lesions with ointments on water-soluble base]

Treatment of patients with thermal burns by ointments prepared on a water-soluble base (Dioxidine and Dioxicol) makes it possible to reduce the bacterial dissemination within a short time and prepare the wound for autodermoplasty which, in turn, reduces the danger of the development of infectious complications. In addition to a marked antimicrobial effect, the ointment possess high hydrophobic and hydrophilic properties and do not induce allergic reactions and side effects.

Evaluation of the release and efficacy of two new antibacterial agents from different ointment bases

The in vitro release of rosoxacin (1) and oxolinic acid (2) from three different ointment bases including a revised water washable (NF), an oleaginous, and an O/W emulsion ointment base was studied. Among the bases evaluated, the revised water washable base provided the best release of the two drugs as revealed from the values of the release rate constant (K). The amounts released of both drugs from the revised water washable base showed direct relationship with the concentration of the drug in the ointment. In addition, the effect of some additives on the amount released of both drugs from the different bases has been investigated. The release of 1 from the revised water washable base had been enhanced by adding 0.2% Tween 80 or 10% ethanol, but addition of 10% of N,N-dimethylacetamide and polyvinylpyrrolidone (PVP) led to retardation of the release of the drug. Furthermore addition of 10% polyethylene glycol (PEG) 200, N,N-dimethylacetamide, or ethanol led to enhancement of the release of the drug from both the oleaginous and the emulsion bases. On the other hand, the release of 2 from the revised water washable base had been enhanced only on addition of 0.2% Tween 80 and been retarded by adding 10% ethanol, N,N-dimethylacetamide or PVP to the formula. The release of 2 from the oleaginous, as well as the emulsion bases had been enhanced by 10% PEG 200. However urea was found to show no pronounced effect on the release of the two drugs from the different ointment bases.(ABSTRACT TRUNCATED AT 250 WORDS)

[Use of multicomponent ointments on a hydrophilic base in the prevention and treatment of postpartum endometritis]

Curative efficiency of hydrophilic-base multicomponent ointments was assessed in patients with puerperal endometritis with respect to hospital strains causing pyoseptic complications. Rationale are given for the choice of the ointment with respect to specific requirements to drugs, used for such purposes. Etiologic contribution of opportunity organisms (both aerobic and anaerobic ones) to the pathologic condition in identified. A method has been developed for local treatment of endometritis with Dioxicol ointment, which promoted a more rapid recovery of the patients.

Short contact dithranol therapy: advantages of a stiff emulsifying ointment base

In a single blind trial, 16 in-patients with psoriasis were treated with short contact dithranol in stiff Lassar's paste and in a stiff emulsifying ointment base of equivalent stiffness. The preparations were equally effective in clearing psoriasis and well tolerated. Perilesional treatment burns, reported with soft ointments, were not seen with the stiff emulsifying ointment preparation. Furthermore, unlike the paste, excess stiff emulsifying ointment can be removed by simply wiping with a moistened cloth, thus greatly facilitating home management of psoriasis.

0.05 percent betamethasone dipropionate in optimized cream vehicle for psoriasis

A multicenter open clinical evaluation of 0.05 percent betamethasone dipropionate in optimized cream vehicle for the treatment of psoriatic lesions was conducted to investigate its efficacy. There were 348 patients with moderate to severe psoriasis who completed the three-week clinical trial. Three hundred and ten patients used the cream twice a day and another 38 patients used it once a day. All patients responded well to treatment. Significant improvement was observed at all follow-up visits on days 8, 15, and 21 (p less than 0.001) for measures of erythema, induration, and scaling of lesions. The response was equally impressive whether the patient's psoriatic status prior to the treatment was stable or worsening, involved more than 50 percent of the skin surface or less, or had lasted more than ten years or less. The response of psoriasis to once-a-day application of cream was as good as that seen with twice-a-day application. Side effects, noted in a small percentage of patients, were burning, dry skin, and pruritus. We conclude that the cream is a safe and highly effective treatment for psoriasis. The once-a-day application is probably adequate for control of psoriasis.

Benzoyl peroxide in the treatment of acne vulgaris: a double-blind, multi-centre comparative study of 'Quinoderm' cream and 'Quinoderm' cream with hydrocortisone versus their base vehicle alone and a benzoyl peroxide only gel preparation

A double-blind, multi-centre general practice study was carried out to compare the effectiveness of benzoyl peroxide/potassium hydroxyquinoline sulphate cream, with or without hydrocortisone, its aqueous astringent cream base alone, and a benzoyl peroxide alcoholic gel in the treatment of 107 patients with acne vulgaris. Patients on entry were allocated at random to one of four treatment groups and instructed to apply the medication twice daily to all affected areas for 12 weeks. Assessments of the severity of acne on the face, chest and back, and response to treatment were made at 2, 4, 8 and 12 weeks. Acceptability of the treatment, i.e. 'greasiness', was also assessed by patients. The results showed that the combination cream preparation produced a greater reduction in acne scores than did the base or benzoyl peroxide alone. The addition of 1% hydrocortisone eliminated the flare reaction to benzoyl peroxide seen in patients in the other two active treatment groups. The majority of patients found the preparations cosmetically acceptable.

Effect of topical applications of silver sulfadiazine on the natural killer cell activity in a rat model of thermal injury

The effect of topical application of silver sulfadiazine cream on the natural killer (NK) cell cytotoxicity was studied in a rat model of thermal injury. The rats were given a 30% total body surface area scald injury and the NK cell cytotoxicity was studied in rats at different days postinjury with or without treatment with silver sulfadiazine. The NK cell activity was observed to be significantly (P less than .0025) suppressed at day 7 postinjury in nontreated burned rats compared with control sham burned animals. Interestingly, in rats treated with silver sulfadiazine twice daily, no suppression in NK cell activity was observed. The application of base cream (without silver sulfadiazine) did not have any significant effect on the NK cell activity in burned rats. The data show that the effect of silver sulfadiazine on NK cell activity may be due to the sulfadiazine component, since the serum levels of sulfadiazine (33.7 +/- 1.9 micrograms/dL) were observed to be maximal at day 7 postinjury.

Connective tissue reactions to 3% tetracycline ointment in rat skin

The connective tissue reactions to 3% tetracycline ointment were studied in 14 Sprague-Dawley white male rats. Using polyethylene tubes, the ointment was implanted subcutaneously in the pouches surgically created on the backs of the experimental group. Empty tube implants, tubes with the vehicle (vaseline/lanolin), and a sham operation (surgical pouches with no implant) served as controls. The animals were killed on day 14 and tissue blocks were taken containing the tubes and a generous amount of the peripheral connective tissue. The connective tissue surrounding the tube opening furthest from the surgical incision was histologically examined for the severity of tissue reaction (STR), the number of inflammatory cell infiltrates (II), and the spread of the reaction area (RSI). The data were statistically analyzed. The sham operation group showed minimal inflammatory response. All three parameters (STR, II, RSI) were significantly greater in the tetracycline group when compared with the empty tube group at 0.05 level of significance. There were significant differences between the mean values of the STR and RSI scores in the tetracycline and vehicle groups (groups 1 and 2). The vehicle group (group 2) had significantly higher STR and II values than the empty tube group (group 3); however, the RSI scores were not statistically different. Necrosis was observed in the reaction site in group 1 and vacuole-containing macrophages were noted in groups 1 and 2. This study, although an animal investigation, questions the use of topical 3% tetracycline ointment on sutured surgical flaps.

Experimental study on topical antimicrobial agents in burns

Numerous organic silver salts have been tested against a virulent strain of Pseudomonas aeruginosa which had been deliberately applied to the scalded tails of mice and deeper scald wounds on the backs of rabbits. Silver pipemidate was found to be more effective than silver sulphadiazine in treating these infected wounds.

[Experimental results of the optimization of external prednisolone therapy]

The initial steps of any topical therapy are characterized by the degree of liberation of the agent from the ointment base and their penetration into different skin layers. A high percentage of the topically applied prednisolone does not penetrate into the skin and may be removed from the skin surface even after some time. By altering the functional structure of the horny layer and considerably increase of prednisolone liberation from ointment bases urea is a effective penetration promotor also for prednisolone. The increased prednisolone penetration into human skin from urea containing ointment correspond with the degree of blanching results by vasoconstriction test under in vivo conditions. The resulting penetration optimation of prednisolone has two possible applications in topical therapy: an increased therapeutic effect for a given prednisolone concentration and a given therapeutic effect could be obtained with a reduced prednisolone concentration.

[Extraction and determination of prednisolone in drugs and excipients in ointments and creams and the uniformity of distribution in prednisolone ointment]

For the purpose of measuring the contents of prednisolone in low concentrated ointments and creams an instruction was elaborated that includes several steps of extraction, in the resulting solution of which the assay of the steroid by Blue Tetrazolium reaction will be done. The procedure permits the determination of prednisolone in presence of most of usual ingredients of ointment bases except wool alcohols. Also no influence is given by some remedies combined with prednisolone for topical application except coal tar solution. The results confirm a correct reflection of the steroid contents declared respectively the recovery of the steroid added to various ointment bases. Introducing discussion to content uniformity concerning low concentrated ointments is made, and some deviations are shown.

The stability and blanching efficiency of some Betnelan-V cream dilutions

In this study Betnelan-V cream was diluted with Beeler's basis and Cold cream. Cold Cream reduced the skin-blanching activity of the original cream more than Beeler's base. The stability of betamethasone-17-valerate was better in a Beeler's basis dilution than in a Cold cream dilution.

Stability of chlortetracycline hydrochloride and chloramphenicol in some ophthalmic ointment bases

The stability of chlortetracycline hydrochloride at 25 and 35 degrees C in absorption base with and without antioxidant decreased during storage for 12 months, while, in water-in-oil emulsion base the medicament was more stable than in oil-in-water emulsion ointment bases. Chloramphenicol was more stable in the absorption base that contained lanolin than in the base which contained cetyl alcohol. Chloramphenicol was more stable in oil-in-water than in water-in-oil emulsion bases. The decomposition rate constant of chlortetracycline hydrochloride and chloramphenicol followed first order kinetics, when the stability study was carried out at 25 and 35 degrees C.

Hyperosmolality induced by propylene glycol. A complication of silver sulfadiazine therapy

An 8-month-old male infant was treated with topical silver sulfadiazine for a burn and complicating toxic epidermal necrolysis involving 78% of his total body surface area. Transdermal absorption of propylene glycol from the silver sulfadiazine produced hyperosmolality with an increased osmolal gap. A peak propylene glycol concentration of 1,059 mg/dL was documented, and its osmotic effect was that predicted from its concentration. Our data support either zero-order elimination at a rate of 13.5 mg/dL/hr or first-order elimination with a half-life of 16.9 hours. Elevated concentrations of propylene glycol may have contributed to the patient's cardiorespiratory arrest. The osmolal gap may be used as a screen for suspected propylene glycol intoxication in selected clinical settings.

Studies on the release of solubilized drugs from ointment bases. Part 10: Modelling of the drug release process of chloramphenicol from emulsive ointments (W/O)--discussion

A mathematical model has been analyzed for the liberation process of substances (chloramphenicol) from emulsive ointments (W/O). Limitarying approximations have been derived which are useful for practical calculations. These approximations have been elaborated for the following cases: since the mass transfer resistance of diffusing substance occurs in the continuous phase, since the mass transfer resistance occurs only in the dispersed phase, then the mass transfer resistance in both phases is comparable. Experimental investigations have been carried out for the liberation process of substances from emulsive ointments. A good qualitative agreement has been found between the theoretical projections and experimental results.

Studies on the release of solubilized drugs from ointment bases. Part 9: Modelling of drug release process of active substance from emulsive ointments (W/O)--the mathematical model

A new mathematical model of the release process of solubilized active substance from emulsive (W/O) ointments is proposed. This model is based on Fick's diffusion law and additional assumptions. The most important assumption is recognition of the heterogeneous character of emulsive ointments. An equation has been derived, which expresses the functional relationship between the quantity of substance liberated from the ointment and the period of release.

Liquid crystals as a potential ointment vehicle

A lecithin-water lyotropic liquid crystal was used as an ointment vehicle for a hydrocortisone formulation. The hydrocortisone was soluble in the liquid crystalline phase up to 5% by weight. The diffusion coefficient determined for the hydrocortisone in the liquid crystalline phase was 5.5 X 10(-9) cm X s-1, which is four magnitudes higher than the corresponding value for skin.