When to hold nifedipine?

From the Guidelines

Nifedipine should be held in patients with certain conditions, including hypotension, heart failure, and hemodynamic instability, as well as in those with significant bradycardia or atrioventricular (AV) block.

Conditions to Hold Nifedipine

• Hypotension (systolic blood pressure less than 90 mm Hg) 1
• Heart failure (HF) or left ventricular (LV) dysfunction 1
• Hemodynamic instability 1
• Significant bradycardia (heart rate less than 50 beats per minute) 1
• Atrioventricular (AV) block (except with a functioning implanted pacemaker) 1

Additional Considerations

• Concomitant beta blockade: Immediate-release nifedipine is not recommended for unstable angina (UA) or non-ST-elevation myocardial infarction (NSTEMI) except with concomitant beta blockade 1
• Monitoring: Patients on nifedipine should be monitored for signs of hypotension, edema, and other adverse effects 1
• Dose adjustment: The dose of nifedipine may need to be adjusted in patients with renal impairment or other comorbidities 1

From the FDA Drug Label

WARNINGS Excessive Hypotension Although in most patients the hypotensive effect of nifedipine is modest and well tolerated, occasional patients have had excessive and poorly tolerated hypotension. In nifedipine-treated patients where surgery using high dose fentanyl anesthesia is contemplated, the physician should be aware of these potential problems and, if the patient's condition permits, sufficient time (at least 36 hours) should be allowed for nifedipine to be washed out of the body prior to surgery

• Hold nifedipine:
  • When excessive hypotension occurs
  • At least 36 hours before surgery using high dose fentanyl anesthesia, if possible
  • When discontinuing nifedipine, the dosage should be decreased gradually with close physician supervision 2
• Clinical considerations:
  • Beta-blocker withdrawal: Patients recently withdrawn from beta blockers may develop a withdrawal syndrome with increased angina, and initiation of nifedipine treatment will not prevent this occurrence 2
  • Congestive heart failure: Rarely, patients have developed heart failure after beginning nifedipine, especially those with tight aortic stenosis 2

From the Research

Nifedipine Administration

• Nifedipine can be administered buccally, sublingually, or orally, with different onset and peak effects for each route 3.
• The duration of effects is four to six hours regardless of the route of administration 3.
• Sublingual nifedipine can be used to control hypertensive urgencies and emergencies, with a dose of 10 mg for patients with diastolic blood pressure (DBP) of 120 to 139 mm Hg, and 20 mg for patients with DBP over 140 mm Hg or with left ventricular hypertrophy or failure, renal disease, hypertensive encephalopathy, angina, papilledema 4.

Dosage and Frequency

• The dose response and length of action of nifedipine capsules and tablets have been studied, with 5 mg capsules being less effective than 10 and 20 mg capsules or 20 mg tablets 5.
• Nifedipine tablets are as effective as capsules, though they may be longer acting, particularly around 6 hours after the last dose 5.
• Slow release nifedipine tablets can be administered once or twice daily, with twice daily administration inducing a significant downward shift in the blood pressure pattern 6.

Special Considerations

• The nifedipine gastrointestinal therapeutic system (GITS) provides rate-controlled-release and once-daily administration, with approximately zero-order delivery of the drug 7.
• The GITS formulation provides drug concentrations that reach a plateau within 6 hours after administration of a single dose, and continue at that concentration until at least 24 hours after administration 7.
• Drug delivery by the nifedipine GITS is unaffected by changes in pH and gastrointestinal (GI) motility, but the rate of drug release can increase slightly with food intake 7.