Nifedipine
Nifedipine
Procardia, Procardia XL, Adalat CC, Afeditab CR
Experience
No personal reports yet
No clinical reports yet
Log in to add your own experience.
Problems
No problems yet. Be the first to suggest one.
+ Add a problemTitration strategies
No titration strategies yet. Be the first to suggest one.
Effects
No effects listed yet. Be the first to suggest one.
Relevant anecdote
No anecdotes yet. Share a relevant one.
Relevant Literature
No literature entries yet.
Log in to submit relevant literature.
Summary
Classes
Common uses
Hypertension0, Vasospastic (Prinzmetal) angina0, Stable angina0, Severe hypertension in pregnancy (oral)0, Preterm labor (off-label tocolysis)0, Raynaud's phenomenon0
Pharmacy
Starting dose
ER 30-60 mg PO once daily; immediate-release 10 mg PO TID (now rarely used for hypertension due to reflex tachycardia)
Preparations
10, 20 mg IR capsules; 30, 60, 90 mg ER tablets
US FDA Max
120 mg/d (ER); IR not for chronic hypertension
Pharmacology
Routes
Oral; sublingual IR is discouraged (uncontrolled BP drops, MI reports)
Onset
IR 20 minutes; ER ~6 hours
Duration
IR 4-8 hours; ER 24 hours
Half-life
2-5 hours (IR); ER formulations extend functional duration via osmotic/matrix release[1]
Bioavailability
~50% IR (extensive first-pass via CYP3A4); ER products release-rate-limited[1]
Pregnancy
Oral nifedipine is one of the preferred agents for severe hypertension in pregnancy and for tocolysis in preterm labor.[citation needed]
Legal status
Rx-only in US
Purported mechanism
Nifedipine is a dihydropyridine calcium channel blocker that selectively inhibits L-type voltage-gated calcium channels in vascular smooth muscle, producing peripheral and coronary arterial vasodilation; cardiac myocyte and AV nodal effects are minimal compared with non-dihydropyridines like diltiazem and verapamil.0 Immediate-release nifedipine's rapid vasodilation and reflex sympathetic activation drove the early 1990s safety concerns that led to ER-only chronic use; sublingual IR is contraindicated. CYP3A4 substrate with substantial grapefruit/itraconazole interactions[1].
References
- ↑ 1.0 1.1 1.2 FDA Prescribing Information, Procardia XL (nifedipine), Pfizer, current revision. https://www.accessdata.fda.gov/drugsatfda_docs/label/2013/018612s045lbl.pdf