In the treatment of essential hypertension. Nifedipine should normally be used in those patients in whom treatment with diuretics or beta-blockers has been ineffective, or has been associated with unacceptable adverse effects. In pregnancy, during lactation, and in women of childbearing potential. Fetal malformations and adverse effects on pregnancy have been reported in animals. Hypersensitivity to nifedipine.
Nifedipine is contraindicated in patients with cardiovascular shock.
The mechanism of this effect is not established. Initiation of nifedipine treatment will not prevent this occurrence and might be expected to exacerbate it by provoking reflex catecholamine release. There have been occasional reports of increased angina in a setting of beta-blocker withdrawal and initiation of nifedipine. If a beta-blocker has to be discontinued, it must be tapered off gradually rather than stopped abruptly. Rarely, patients, usually receiving a beta-blocker, have developed heart failure after beginning nifedipine therapy.