Nicorandil should not be prescribed unless first-line angina treatments, such as beta-blockers and calcium-channel blockers, are inadequate, contraindicated or not tolerated.
The restriction on use has been introduced following reports of serious skin, mucosal and eye ulceration in patients treated with the anti-anginal. Nicorandil-induced ulcers do not respond to conventional treatment and persist until the drug is withdrawn.
Risk factors for ulceration
Patients taking NSAIDs or corticosteroids are at increased risk of gastrointestinal ulceration and those with diverticular disease may be at increased risk of fistula formation or bowel perforation. Caution is advised when prescribing nicorandil in such individuals.
Nicorandil must be withdrawn promptly if ulceration develops and the advice of a cardiologist sought if angina symptoms worsen.
The time to onset of ulceration ranges from shortly after initiating nicorandil treatment to several years after starting nicorandil. It is not known how nicorandil causes ulceration.
Hypotension and hyperkalaemia
Nicorandil can cause hypotension and is now contraindicated in hypovolaemia, acute pulmonary oedema and in combination with guanylate cyclase stimulators such as riociguat.
Rare cases of severe hyperkalaemia have been reported in nicorandil-treated patients and the drug should be used cautiously in combination with medicines that increase potassium levels, especially in patients with moderate to severe renal impairment.
Nicorandil should also be used with caution in patients with heart failure (NYHA class III or IV), glucose 6 phosphate dehydrogenase deficiency, or taking the premature ejaculation treatment dapoxetine.
Nicorandil, which is available as Ikorel and as generic tablets, is a vasodilator with a dual mechanism of action. It activates potassium channels and increases intracellular cGMP levels to cause relaxation of both venous and arterial smooth muscle.
Updated 25 January 2016
MHRA confirms nicorandil now second-line treatment for angina
On 21 January 2016, the Medicines and Healthcare products Regulatory Agency confirmed the restrictions to the licensed indication of nicorandil.