| Most side-effects are consequences of the vasodilatory effects of nifedipine. Side-effects are generally transient and mild, and usually occur at the start of treatment only. They include headache, flushing and, usually at higher dosages, nausea, dyspepsia, heartburn, constipation, diarrhoea, dizziness, lethargy, skin reactions (rash, urticaria and pruritus), paraesthesia, hypotension, palpitation, tachycardia, dependent oedema, increased frequency of micturition, eye pain, depression, fever, gingival hyperplasia ,telangiectasia and erythema multiforme.Other less frequently reported side-effects include myalgia, tremor, pemphigoid reaction and visual disturbances. Impotence may occur rarely. Mood changes may occur rarely. Excessive falls in blood pressure may result in cerebral or myocardial ischaemia or transient blindness.As with other sustained release dihydropyridines, exacerbation of angina pectoris may occur rarely at the start of treatment with sustained release formulations of nifedipine. The occurrence of myocardial infarction has been described although it is not possible to distinguish such an event from the natural course of ischaemic heart disease. Ischaemic pain has been reported in a small proportion of patients following the introduction of nifedipine therapy. Although a 'steal' effect has not been demonstrated, patients experiencing this effect should discontinue nifedipine therapy.There are reports in older men on long-term therapy of gynaecomastia which usually regresses upon withdrawal of therapy.Side-effects which may occur in isolated cases are photosensitivity, exfoliative dermatitis, systemic allergic reactions, purpura and a worsening of myasthenia gravis. Usually, these regress after discontinuation of the drug.Rare cases of hypersensitivity-type jaundice have been reported. In addition, disturbances of liver function such as intra-hepatic cholestasis may occur. These regress after discontinuation of therapy.
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