Nifedipine is a dihydropyridine calcium channel blocker that relaxes vascular smooth muscle, reducing peripheral vascular resistance and blood pressure.
Also known as: Adalat, Procardia
Calcium channel blocker + PDE5 inhibitor: risk of severe hypotension.
Nifedipine blocks vascular L-type calcium channels, causing vasodilation. Sildenafil inhibits PDE5, raising cGMP and potentiating NO-mediated vasodilation. The synergistic combination can cause severe symptomatic hypotension (systolic BP <90 mmHg). Risk is higher in elderly, dehydrated patients, or those on multiple antihypertensives. If combination is essential, reduce sildenafil to 25 mg and monitor BP frequently.
CCB + PDE5 inhibitor: potentially fatal severe hypotension. Both cause vasodilation. If essential, reduce sildenafil to 25 mg and monitor BP.
Both cause vasodilation. The combination can cause severe symptomatic hypotension. Consider reduced sildenafil dose.
DailyMed/FDA (NIH/NLM) — approved Nifedipine label: https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=b8b8cfee-ea71-44c2-81af-675efecfdf15
Increases nifedipine levels (inhibits intestinal CYP3A4).
Avoid excessive amounts of grapefruit juice.
DailyMed/FDA (NIH/NLM) — approved Nifedipine label: https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=b8b8cfee-ea71-44c2-81af-675efecfdf15
No documented disease interactions.
Use only if benefit justifies risk. May cause maternal and fetal hypotension.
Avoid in 1st trimester if possible.
Excreted in breast milk in low concentrations. Generally compatible.
Use the minimum effective dose. Monitor maternal and fetal blood pressure.
DailyMed/FDA (NIH/NLM) — approved Nifedipine label: https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=b8b8cfee-ea71-44c2-81af-675efecfdf15
Clinical and educational support tool. The information does not replace a medical prescription or the opinion of a qualified healthcare professional.
Selective dihydropyridine L-type calcium channel blocker that inhibits transmembrane calcium influx into vascular smooth muscle.
Blocks L-type calcium channels in vascular smooth muscle, preventing Ca²⁺ influx and causing smooth muscle relaxation and vasodilation.
Oral bioavailability: 45-68% (capsules). Food increases absorption. Tmax: 30-60 minutes (capsules).
Metabolised by CYP3A4. Inhibited by ketoconazole, erythromycin. Induced by phenytoin, carbamazepine, rifampicin.
2-5 hours. Elimination: ~80% urine (metabolites), ~20% faeces. Extensive first-pass metabolism.
Medicines from the same therapeutic group (ATC classification) or the same pharmacological class.
