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- Uterine relaxant
- Threatened premature labour
Forms and strengths
- 10 mg immediate-release soft capsule or tablet
Dosage and duration
- 10 mg by oral route, to be repeated every 15 minutes if uterine contractions persist (max. 4 doses or 40 mg), then 20 mg by oral route every 6 hours
The total duration of treatment is 48 hours.
Contra-indications, adverse effects, precautions
- Do not administer to patients with severe cardiac disease (recent myocardial infarction, unstable angina).
- Do not administer if systolic blood pressure is below 90 mmHg.
- May cause:
- headache, flushing, peripheral oedema (common adverse effects at the start of treatment);
- dizziness, hypotension, tachycardia, nausea, gingival hyperplasia, rash.
- Stop nifedipine if ischaemic chest pain occurs or existing pain increases after starting treatment.
- Do not combine with magnesium sulphate, salbutamol IV, and other calcium channel blockers.
- Monitor combination with cimetidine (enhances hypotensive effects), phenytoin (risk of phenytoin overdose), rifampicin (efficacy of nifedipine diminished), itraconazole (increased risk of oedema), beta-blockers (increased adverse cardiac effects).
- Pregnancy: CONTRA-INDICATED during the first trimester. Never administer sublingually (risk of foetal death from placental hypoperfusion).
- Breast-feeding: avoid
- Nifedipine is a calcium channel blocker that is also used in the management of hypertension at doses of 10 to 40 mg 2 times daily or 20 to 90 mg once daily, depending on the sustained-release form used. Immediate-release forms of nifedipine should not be used in either long-term treatment of hypertension or treatment of hypertensive crisis (risk of excessive fall in blood pressure and cerebral or myocardial ischaemia in patients with coronary artery disease).