Nicorandil and idiopathic anal ulceration

Nicorandil-induced colovesical fistula in a patient with diverticular disease

Nicorandil's adverse effects can cause severe patient morbidity and can present to any specialty. Those with underlying diverticular disease are most susceptible. Medication reviews are vital for patients presenting with ulcer or fistula symptoms.

Nicorandil ameliorates bleomycin-induced pulmonary fibrosis in rats through modulating eNOS, iNOS, TXNIP and HIF-1α levels

Bleomycin (BLM) is one of the most common anti-cancer drugs used to treat numerous types of tumors. However, pulmonary toxicity is considered the most dramatic effect of BLM. Therefore, BLM has been frequently used for induction of pulmonary fibrosis. This study aimed to evaluate the effect of nicorandil on BLM-induced pulmonary fibrosis and explore the possible mechanisms. BLM was instilled intratracheally into male Sprague-Dawley rats as a single dose (5 mg/kg) and oral nicorandil was given (30 mg/kg/day) for 6 weeks after BLM challenge. At the end of experimental period, rats were sacrificed, and lung histopathology and biochemical parameters were evaluated. Nicorandil therapy attenuated lung inflammation and fibrosis elicited by BLM. Nicorandil significantly reduced total protein content, lactate dehydrogenase (LDH) activity and total and differential cell counts. Moreover, nicorandil diminished lung levels of malondialdehyde and total nitrite/nitrate, in addition to increasing lung contents of reduced glutathione and superoxide dismutase activity. Nicorandil reduced lung and bronchoalveolar lavage fluid contents of hypoxia inducible factor-1α (HIF-1α) and lung content of thioredoxin-interacting protein (TXNIP). Besides, nicorandil significantly improved histological lesions and reduced collagen deposition as well as hydroxyproline content. Immunohistochemical examination revealed that nicorandil-treated rats exhibited significant diminutions in protein expression levels of transforming growth factor beta-1(TGF-β1) and inducible nitric oxide synthase (iNOS) and enhanced pulmonary protein expression of endothelial NOS (eNOS). In conclusion, these results illustrate the possible potential effects of nicorandil for managing pulmonary fibrosis caused by BLM.

Nicorandil-induced ulcerations: a 10-year observational study of all cases spontaneously reported to the French pharmacovigilance network

Nicorandil-induced ulcers remain often poorly recognised, with a late diagnosis and an inadequate management. We aimed to provide a clinical overview of the 148 spontaneously reported cases of nicorandil-induced ulcers to the French pharmacovigilance network between 2005 and 2014 and to complete this picture with worldwide published cases over the same period. Spontaneously reported nicorandil-induced ulcers were mainly mucosal (oral and anal) with a previous trauma in 23·0% of patients, revealed by a severe complication in 12·8% of cases. The mean cumulative dose of nicorandil was higher in serious cases. The median delay between the start of nicorandil use and the onset of the ulcer was 23·4 months, and after the ulcer was diagnosed, the median time to incriminate nicorandil was still 3·3 months, being shorter for mucosal ulcerations than for cutaneous ulcerations (5·2 versus 14·0 months, P = 0·001). The anatomic distribution in the 199 published cases differed slightly, but delays were similar. The hypothesis of mechanism becomes more precise, leaving no doubt about the necessity to discontinue the treatment. Practitioners need to be aware that nicorandil-induced ulcers can occur in many locations, possibly multiple and complicated, and should be simply managed by discontinuing treatment with no further reintroduction of nicorandil.

Potassium Channelopathies and Gastrointestinal Ulceration

Potassium channels and transporters maintain potassium homeostasis and play significant roles in several different biological actions via potassium ion regulation. In previous decades, the key revelations that potassium channels and transporters are involved in the production of gastric acid and the regulation of secretion in the stomach have been recognized. Drugs used to treat peptic ulceration are often potassium transporter inhibitors. It has also been reported that potassium channels are involved in ulcerative colitis. Direct toxicity to the intestines from nonsteroidal anti-inflammatory drugs has been associated with altered potassium channel activities. Several reports have indicated that the long-term use of the antianginal drug Nicorandil, an adenosine triphosphate-sensitive potassium channel opener, increases the chances of ulceration and perforation from the oral to anal regions throughout the gastrointestinal (GI) tract. Several of these drug features provide further insights into the role of potassium channels in the occurrence of ulceration in the GI tract. The purpose of this review is to investigate whether potassium channelopathies are involved in the mechanisms responsible for ulceration that occurs throughout the GI tract.

Nicorandil, Gastrointestinal Adverse Drug Reactions and Ulcerations: A Systematic Review

INTRODUCTION

Nicorandil is a popular anti-anginal drug in Europe and Japan. Apart from some common adverse drug reactions (ADR), its safety is satisfactory. Several reports have suggested a link between nicorandil, gastrointestinal (GI) ulceration and fistulas. The review aims to critically appraise, synthesize and present the available evidence of all known GI ADR per anatomical location.

METHODS

The study complied with the PRISMA statement. Literature and pharmacovigilance databases were used to provide rate and/or calculate parameters (median age, median dose, history of symptoms, length of therapy and healing time after withdrawal of the drug). Differences in distribution of quantitative variables were analyzed via Mann-Whitney test. Correlation between quantitative variables was assessed with a Spearman's correlation coefficient. A p value <0.05 was significant.

RESULTS

Oral ulcerations occur in 0.2% of the subjects, anal ulcerations are present between 0.07% and 0.37% of patients. Oral and distal GI involvements are the most common ADR (28-29% and 27-31% of all GI ADR, respectively). The hepatobiliary system, the pancreas and salivary glands are not affected by nicorandil exposure. The time to develop oral ulcerations is 74 weeks among people on <30 mg/day compared to only 7.5 weeks in individuals on higher regimens (p = 0.47). There is a significant correlation between dose and ulcer healing time (Spearman's 0.525, p < 0.001).

CONCLUSIONS

Ulcerative disease is a very commonly reported GI ADR. A delayed ulcerative tendency supports the hypothesis of an ulcerogenic metabolite. Nicorandil seems to act as a cause of the ulcerations, but appears to also work in synergy with other promoting factors. Whether the action of the metabolites relies on a specific mechanism or a simple chemical ulceration is still to be established.

Nicorandil-induced colonic ulceration

A 76-year-old woman with significant cardiovascular comorbidities was investigated under general surgery for weight loss and change in bowel habit. Endoscopic investigations revealed a large ulcer extending from the ileocaecal valve to the ascending colon. Histology of the biopsies from this site revealed chronic inflammation and reactive changes. However, considering the history and suspicious radiological and endoscopic findings, decision was made at a multidisciplinary meeting to offer laparoscopic right hemicolectomy. Owing to complications, the procedure was converted to an open surgery. Postoperatively, histology of resected bowel revealed chronic inflammation and no evidence of malignancy. In light of an 8-year history of nicorandil therapy, the histological changes were thought to represent nicorandil-induced colonic ulceration.

Nicorandil associated pinna ulceration: a new entity for an otolaryngologist

Nicorandil induced ulceration is a phenomenon that is becoming increasingly recognised in clinical practice. However, most cases of Nicorandil induced ulcers appear at the muco-cutaneous interface zones. We report a case of Pinna ulceration where Nicorandil appeared to be the chief aetiological factor. Having ruled out all reasonable alternatives Nicorandil treatment was discontinued and a rapid improvement in the ulcer was observed. To the best of our knowledge this is the first recorded case of external ear ulceration related to Nicorandil use.

Nicorandil associated anal ulcers: an estimate of incidence

INTRODUCTION

Nicorandil is a commonly prescribed antianginal medication that has been found to be associated with painful anal ulceration. The incidence of this complication is unknown. We have used the best data available to us to make an estimate of this figure in a health district with a remarkably stable population of approximately 200,000 people.

METHODS

using an electronic search of all letters generated from colorectal and gastroenterology clinics as well as endoscopy reports from January 2004 to November 2010, patients with anal ulceration who were taking nicorandil were identified. Other causes of ulceration were excluded by biopsy in the majority of cases. The central hospital and community pharmacy database was interrogated to estimate the number of patients who were prescribed nicorandil over a six-year period (2004-2010).

RESULTS

A total of 30 patients (24 men, 6 women) with a median age of 79.5 years were identified who fulfilled the criteria of: taking nicorandil; having no other identified cause for anal ulceration; and achieving eventual healing after withdrawal of nicorandil. In the six-year period an estimated mean of 1,379 patients were prescribed nicorandil each year. The mean annual incidence of anal ulcers among nicorandil users is therefore calculated to be in the region of 0.37%.

CONCLUSIONS

Anal ulceration appears to occur in approximately four in every thousand patients prescribed nicorandil each year. Prescribing physicians should explain the risk of this unpleasant complication to their patients.

Nicorandil: from ulcer to fistula into adjacent organs

Nicorandil is an original vasodilatator used to control angina by decreasing cardiac preload and afterload. Since 1997, many reports of single or multiple nicorandil-induced ulcerations have been published. To date, eight cases of nicorandil-induced fistula into adjacent organs have been described. The pathogeneses of nicorandil-induced ulceration and fistula into adjacent organs are not yet elucidated. The two main hepatic biotransformation pathways of nicorandil are denitration and reduction of the alkyl chain leading to nicotinamide and niconitic acid which merge into the endogenous pool of nicotinamide adenine dinucleotide/phosphate. This merging which is known as saturable, may contribute to a slow and abnormal distribution of nicotinamide and nicotinic acid out of the endogenous pool. Under these special conditions, providing these two molecules in situ, nicotinic acid associated with nicotinamide may ulcerate rather recent or maintained trauma. Ulcers and fistulae induced by nicorandil heal after withdrawal. Surgical intervention is unnecessary and inappropriate as it is ineffective and exacerbates morbidity. All practitioners should be correctly informed about these serious but preventable nicorandil side effects, which mostly occur in the elderly and fragile population. In the absence of corrective measures, withdrawal of this original and active drug should be considered.

Nicorandil-induced rectovaginal fistula

An 82-year-old woman was admitted with feculent vaginal discharge and bleeding per vagina. Investigations revealed the presence of a rectovaginal fistula with no obvious etiology. Due to the surgical team's previous experience with nicorandil-induced ulceration, the drug was stopped. The rectovaginal fistula healed completely within 6 months.

Rectal ulceration caused by the anti-anginal nicorandil: Case report of a preventable complication

The association of the anti-anginal drug nicorandil with oral and anal ulceration is becoming more widely recognised, but there are no reports of isolated nicorandil-induced rectal ulceration. Awareness of this condition is poor, and patients often undergo unnecessary surgery for a condition which resolves on stopping the medication.

We report a case of nicorandil-induced rectal ulceration causing rectal bleeding. The patient was spared surgery after awareness of the link with this drug.

This diagnosis should be considered in patients with unexplained gastrointestinal ulceration after exclusion of serious underlying causes. We hope this report will increase awareness amongst physicians and surgeons of this reversible condition.

Nicorandil-induced terminal ileal ulceration--a probable link

Nicorandil, a commonly prescribed anti-anginal agent, has been reported to be associated with ulceration in various parts of the gastrointestinal tract. A 68-year-old general practitioner presented with severe rectal bleeding and abdominal pain associated with terminal ileal ulceration diagnosed by colonoscopy. Capsule endoscopy revealed no other source of bleeding and CT was normal. Diclofenac and/or aspirin were assumed to be causative factors and discontinued. Aspirin was temporarily resumed then discontinued after a second massive, but self-limiting, haemorrhage and persistent abdominal pain. Repeat colonoscopy 5 weeks later confirmed that the previously documented terminal ileal ulceration had worsened. Histopathology was consistent with localised mucosal ischaemia. Nicorandil was withdrawn, after which no further episode of bleeding occurred and his pain settled. Repeat colonoscopy 3 months later confirmed complete healing. This report implicates nicorandil as a cause of terminal ileal ulceration leading to life-threatening rectal bleeding and abdominal pain.

Nicorandil-induced severe perianal ulceration

BACKGROUND

Nicorandil is a potassium channel activator used in the prevention and long-term treatment of angina pectoris. It is widely prescribed and its use is supported by data from powerful randomised controlled trials. The colorectal community is becoming increasingly aware of a subgroup of patients with anal ulceration and other gastrointestinal manifestations of nicorandil use.

METHODS

This study is a retrospective review of patients identified as having nicorandil-induced perianal ulceration. We report our experience of 11 patients.

RESULTS

All eleven patients experienced severe debilitating ulceration of the perianal area and perineum. Multiple therapies were tried unsuccessfully before the association with nicorandil was recognised. Upon recognition of the association of nicorandil with these ulcers, the therapy was stopped resulting in resolution of the perianal symptoms.

CONCLUSIONS

Nicorandil is a rare cause of severe perianal ulceration. This association should be recognised as these ulcers are resistant to other forms of treatment but heal well on ceasing nicorandil use.

Nicorandil-associated ulcerations

This leading article refers to the paper by Abdelrazeq AS, Owen C, Smith L, McAdam JG, Pearson HJ, Leveson SH. Nicorandil-associated para-stomal ulceration: case series Eur J Gastroenterol Hepatol 2006; 18:1293-1295. We apologise to all concerned for the dissociation between the two papers, which was due to an administrative error. Nicorandil is used widely in patients with coronary artery disease. Nicorandil is well tolerated with only minor side effects. Nicorandil's association with oral, anal, gastrointestinal ulceration, and more recently para-stomal ulceration has been reported. Medical awareness of nicorandil association with ulcerations should be high to help avoid unnecessary and harmful treatment as only cessation of the drug would heal the ulceration. Nicorandil is an antianginal drug used for the treatment of symptomatic coronary artery disease. It is characterized by an arterial and venous vasodilator effect with dual mechanism of action. Nicorandil is not a first-line agent in the management of angina but it is used in combination with other antianginal medications in stable and unstable angina. It is generally well tolerated with minor side effects such as headache, nausea, flushing and dizziness. The association of nicorandil with mouth and anal ulcers as well as the association with ulceration throughout the gastrointestinal tract has been reported, and recently, an association with para-stomal ulceration has also been described. Medical awareness of the association of nicorandil with ulceration in any part of the gastrointestinal tract should be highlighted among all medical professionals to help avoid delays in withdrawing the treatment and to avoid unnecessary and sometimes invasive and costly interventions.

Nicorandil related anal ulcer

BACKGROUND

Anal ulceration is uncommon. Patients are typically referred because of severe anal pain, bleeding, discharge, and ulceration. It is important to exclude anal carcinoma, and to consider more unusual causes.

METHODS

A 74-year-old lady presented with severe anal pain and ulceration. This was subsequently noted to be related to nicorandil, a potassium channel activator used in the treatment of angina. Discontinuation of nicorandil and faecal diversion allowed symptom relief and ulcer healing.

CONCLUSION

Knowledge of the association between nicorandil and anal ulceration is essential in order to appropriately diagnose and manage this condition.

Nicorandil-associated para-stomal ulceration: Case series

Nicorandil is a vasodilator used to control severe angina. It has been associated with oral and anal ulceration that resolves upon withdrawal of the drug. We report a series of four patients, all of whom were receiving nicorandil therapy and developed nonspecific para-stomal ulcerations of similar clinical and histological appearance. All ulcers healed on withdrawal of nicorandil with no relapse. To the best of our knowledge, nicorandil-associated para-stomal ulcers have not been reported before. It is imperative to be aware of this association to prevent the persistence of these extremely painful ulcerations, and to avoid unnecessary and inappropriate interventions with substantial morbidity in a group of high-risk patients.

Anal ulceration associated with Nicorandil: case series and review of the literature

BACKGROUND

Use of Nicorandil in the treatment of ischaemic heart disease has been associated with oral, ileal and more recently anal ulceration. We report a series of six cases of peri-anal ulceration in patients on nicorandil therapy, their response to withdrawal of the drug and review the literature.

METHODOLOGY

Systematic case note review of all patients with anal ulceration presenting to a single colorectal unit. Including detailed medical and drug history, morphological and histological appearances of the peri-anal ulcer after biopsy. Nicorandil therapy stopped in conjunction with physician and the progress of the ulcer monitored. Photographs taken before and after cessation of Nicorandil after informed consent. A literature search on Nicorandil combined with the key words: anal, peri-anal, ulceration and adverse drug effects was performed using the Cochrane Library Medline (January 1966 to June 2005) and Embase (January 1974 to June, 2005).

RESULTS

Six patients were identified from our hospital records. Histological examination of all ulcers revealed nonspecific chronic inflammation. Five patients demonstrated healing of ulceration within six weeks of withdrawal of Nicorandil, the remaining patient had circumferential involvement of the anal canal and has not improved at 3-month review. One patient was recommenced on Nicorandil after healing due to refractory angina and ulceration recurred.

CONCLUSIONS

We believe ulceration due to Nicorandil remains widely under diagnosed and the mechanism of ulceration is unclear. Despite diversion colostomy one of our patients continued with peri-anal ulceration, which may suggest a systemic mechanism rather than local irritation. Biopsy of these lesions is essential to exclude neoplastic process and inflammatory bowel disease.