Nifidipin: common spelling variant of nifedipine
Nifidipin is a very common spelling variant of the correct substance name nifedipine. Confusion arises from similar-sounding pronunciation and the swallowed e in the middle of the word. Pharmacologically, the same substance is meant: a calcium channel blocker from the dihydropyridine class. This page summarises the most important aspects again to help patients who searched with the incorrect spelling.
Nifedipine (correct) was introduced in Germany in 1975 as the first dihydropyridine and revolutionised the treatment of hypertension and angina pectoris. Today, mainly extended-release forms are used, since short-acting preparations can cause circulatory problems. Classic brand names are Adalat, Aprical and many generics.
Mechanism of action
Nifedipine blocks voltage-dependent L-type calcium channels, mainly in vascular smooth muscle. This reduces calcium influx into the cell, leading to relaxation of the vessel wall. Effects include:
- Vasodilation of peripheral arterioles with reduction of systemic vascular resistance and blood pressure
- Coronary vasodilation with improved myocardial perfusion
- Reduction of vascular spasm, e.g. in vasospastic Raynaud's phenomenon
- Inhibition of uterine contraction (clinically used as tocolytic)
Unlike verapamil and diltiazem, nifedipine has only minor effects on cardiac conduction and almost no negative inotropy. Reflex tachycardia can occur, especially with short-acting preparations.
Indications
- Arterial hypertension: standard indication, mainly in extended-release form (Adalat OROS, GITS formulations)
- Stable angina pectoris: in combination with beta-blockers or as alternative
- Vasospastic angina (Prinzmetal): classic indication due to coronary vasodilation
- Raynaud's syndrome: primary or secondary, reduces spasms and complaints
- Tocolysis in threatened preterm birth: off-label, standard therapy in many countries
- Hypertensive crisis: short-acting preparations no longer recommended due to dangerous abrupt blood pressure drops
Dosing and administration
Hypertension and stable angina pectoris: extended-release 30 to 60 mg once daily, up to 120 mg per day if needed.
Raynaud's syndrome: extended-release 30 mg once or twice daily, individual adjustment.
Tocolysis: oral administration per institutional protocols, often 10 mg every 15 to 20 minutes for loading, then maintenance dose.
Extended-release tablets must not be split or chewed. Take regardless of meals; avoid grapefruit juice as it significantly increases bioavailability.
Short-acting nifedipine preparations are largely obsolete today, as they can cause reflex tachycardia and unfavourable blood pressure swings.
Side effects
Common: headache, flush (hot feeling, facial reddening), peripheral oedema (especially ankles), tachycardia, dizziness, nausea, constipation, fatigue, gingival hyperplasia with long-term use.
Uncommon: hypotension, syncope, visual disturbance, rash, pruritus.
Rare: paradoxical worsening of angina pectoris, worsening of heart failure, allergic reactions, hepatitis, Stevens Johnson syndrome, leukopenia.
Peripheral oedema:
- Common dihydropyridine side effect, dose-dependent, often at ankles and lower legs
- Pathophysiologically due to arteriolar vasodilation without corresponding venular dilation
- Treatment: dose reduction, switching to other class, combination with ACE inhibitor can reduce oedema
- Diuretics work only partially with this mechanism
Interactions
- Strong CYP3A4 inhibitors (itraconazole, ketoconazole, HIV protease inhibitors, erythromycin, grapefruit juice): increased levels, potentiated effect
- Strong CYP3A4 inducers (rifampicin, phenytoin, carbamazepine, St John's wort): level fall, loss of effect
- Cimetidine: level increase
- Other antihypertensives: additive blood pressure lowering
- Digoxin: rise of digoxin levels
- Tacrolimus: rise of tacrolimus levels
- Magnesium sulphate (in tocolysis): additive neuromuscular effect, caution
Special considerations
Pregnancy: off-label established in tocolysis with good data. In hypertension, individual judgement.
Breastfeeding: small passage into breast milk, possible after individual assessment.
Contraindications: cardiogenic shock, acute myocardial infarction with haemodynamic instability, unstable angina pectoris (for short-acting preparations), severe aortic stenosis, first-trimester pregnancy without clear indication.
Older patients: increased sensitivity, fall risk through hypotension. Low doses recommended, careful titration.
Liver disease: prolonged half-life, dose reduction sensible.
Avoiding grapefruit juice: a single glass can double nifedipine plasma levels, leading to hypotension and tachycardia. Patients should be explicitly informed of this interaction.
Therapy failure: with insufficient effect, review the diagnosis, discuss adherence and possibly switch class, e.g. to amlodipine or lercanidipine.
Related substances
- Nifedipin, correct spelling of the substance
- Enalapril, ACE inhibitor as alternative or combination partner
- Propranolol, beta-blocker in angina pectoris
- Celiprolol, cardioselective beta-blocker
- Clopidogrel in overall cardiovascular care
Frequently asked questions
Is the substance called nifidipin or nifedipine?
The correct name is nifedipine. Nifidipin is a common spelling variant, presumably due to mispronunciation or typing error. Both refer to the same substance.
Why does nifedipine give me swollen feet?
Dihydropyridine calcium channel blockers dilate arterioles more strongly than venules, leading to increased capillary pressure and fluid leakage into tissue. These oedemas are typical and usually harmless. With troublesome forms, dose reduction, combination with an ACE inhibitor or switch to other substances may help.
Why no grapefruit juice?
Grapefruit juice inhibits CYP3A4 in the gut, which breaks down nifedipine. As a result plasma levels rise significantly, which can cause strong blood pressure lowering and tachycardia. Just one glass per day is enough for clinically relevant effects. Other citrus fruits like oranges are not a problem.
Can nifedipine be used in pregnancy?
In tocolysis for threatened preterm birth, nifedipine has been used off-label successfully for decades. In hypertension during pregnancy it is an established option from the second trimester. In the first trimester the indication should be reviewed individually.
Sources
- EMA European Medicines Agency
- BfArM Federal Institute for Drugs and Medical Devices
- AWMF guidelines hypertension and tocolysis
- Gelbe Liste nifedipine monograph
Legal notice and disclaimer
The information on this page is provided for general information purposes only and does not constitute medical advice, diagnosis or treatment recommendation. It does not replace the advice of a licensed physician or pharmacist. Medicines should only be used after a doctor's prescription or pharmacy supply. All information is based on summaries of product characteristics and accepted scientific sources at the time of writing; the current SmPC of the manufacturer is always decisive. Sanoliste accepts no liability for completeness, timeliness or accuracy. In a medical emergency, dial the emergency number 112.