Nifedipine is a medication commonly used to treat high blood pressure and chest pain (angina). It belongs to a class of drugs known as calcium channel blockers. By relaxing blood vessels, it helps to improve blood flow and reduce the workload on the heart. This can lower blood pressure and relieve angina symptoms.

Nifedipine works by blocking the influx of calcium ions into smooth muscle cells in blood vessels and the heart. This action relaxes and widens the blood vessels, allowing blood to flow more easily and reducing the strain on the heart.

Nifedipine (Adalat, Procardia) belongs to the class of dihydropyridine calcium channel blockers. It works by relaxation of the muscles of the heart and blood vessels.

Nifedipine Uses

• Angina:
  • The therapy of chronic stable/vasospastic angina is indicated.
• Hypertension:
  • It is used for controlling blood pressure
• Off Label Use of Nifedipine in Adults:
  • Anal fissure
  • High-altitude pulmonary edema
  • Hypertensive emergency in pregnancy or postpartum 
  • Group 1 Pulmonary arterial hypertension
  • Raynaud phenomenon
  • Tocolysis

Nifedipine dosage in adults

Note:

• Nifedipine is a medicine used for high blood pressure and chest pain.
• It helps blood vessels relax, easing blood flow and reducing heart strain.
• Avoid sublingual (under the tongue) use due to safety risks.
• It comes in two forms: immediate-release capsules taken three times daily, and extended-release tablets taken once daily.
• When switching from one form to another, keep the total daily dose the same.

Nifedipine dose for the treatment of Anal fissure:

• Nifedipine is used topically as a local vasodilator alongside other supportive measures.
• Commercially prepared ointments and gels are not available, so they must be compounded by a licensed facility.
• The recommended dose is 0.2% to 0.3% ointment or gel applied around or directly on the fissure(s) two to four times daily for a duration of four weeks.
• This treatment approach aims to promote healing and alleviate symptoms associated with anal fissures.

Nifedipine treatment dose for the treatment of Angina pectoris:

Chronic Stable Angina (Alternative Agent):

• Prefer beta-blocker as first-line therapy.
• Consider adding long-acting dihydropyridine calcium channel blocker (e.g., ER nifedipine) if symptoms persist on beta-blocker therapy.
• ER nifedipine may also be used if beta-blockers are contraindicated or cause unacceptable side effects.
• Avoid immediate-release nifedipine due to increased adverse effects without beta-blocker.
• Oral Extended-Release Nifedipine Dosage for Chronic Stable Angina:
  • Initial: 30 or 60 mg once daily.
  • Increase gradually over 1 to 2 weeks to achieve effective antianginal dose.
  • Rarely need doses >90 mg/day.
  • Maximum: 120 mg/day.

Vasospastic Angina:

• Can be used alone or with nitrates.
• Avoid immediate-release nifedipine due to increased adverse effects without beta-blocker.
• Oral Extended-Release Nifedipine Dosage for Vasospastic Angina:
  • Initial: 30 or 60 mg once daily.
  • Increase gradually over 1 to 2 weeks to achieve effective antianginal dose.
  • Rarely need doses >90 mg/day.
  • Maximum: 120 mg/day.

Nifedipine dose for the treatment of High-altitude pulmonary edema (adjunctive therapy):

Prevention of High-Altitude Pulmonary Edema:

• Considered as an adjunct to gradual ascent in higher-risk individuals.
• Oral Extended-Release Nifedipine Dosage:
  • 30 mg every 12 hours.
  • Start 24 hours before ascent.
  • Continue for 5 days after reaching maximal altitude.
  • Can extend beyond 5 days in high-risk circumstances where descent is impossible.

Treatment of High-Altitude Pulmonary Edema:

• Used adjunctively with nonpharmacologic measures or as monotherapy if nonpharmacologic measures are not feasible.
• Oral Extended-Release Nifedipine Dosage:
  • 30 mg every 12 hours.

Nifedipine dose for the treatment of Hypertension:

• Consider for initial treatment in patients with blood pressure ≥20/10 mm Hg above goal, in combination with another appropriate agent.
• For patients <20/10 mm Hg above goal, initial monotherapy may be recommended initially, but many patients may eventually require combination therapy.
• Avoid immediate-release nifedipine for acute blood-pressure lowering due to risk of severe hypotension, which can cause cerebral and/or myocardial ischemia.
• Oral Extended-Release Nifedipine Dosage:
  • Initial: 30 or 60 mg once daily.
  • Increase dose as needed based on response and tolerability every 1 to 2 weeks.
  • Usual dosage range: 30 to 90 mg once daily.

Nifedipine dose for the treatment of Hypertensive emergency in pregnancy or postpartum (including acute-onset hypertension in preeclampsia/ eclampsia):

Extended-Release Nifedipine:

• Initial: 30 mg.
• Repeat 30 mg after 1 to 2 hours if target blood pressure is not achieved.
• If blood pressure remains high after the second dose, consider using another class of agents.

Immediate-Release Nifedipine (Alternative Agent):

• Generally reserved for when IV access is not available.
• Some experts avoid its use due to possible severe drops in blood pressure.
• Do not puncture capsule or administer sublingually.
• Initial: 10 mg with fetal heart rate monitoring.
• If blood pressure remains high at 20 minutes, give 10 or 20 mg depending on initial response.
• If blood pressure remains high after 40 minutes, give another dose of 10 or 20 mg depending on previous response.
• If target blood pressure is not achieved after the third dose, consider using another class of agents.

Nifedipine dose for the treatment of Group 1 Pulmonary arterial hypertension:

• Only for rigorously selected patients with positive vasoreactivity test under the care of a pulmonary hypertension specialist.
• European guidelines recommend a 12-hour, sustained-release formulation not available in the United States; dosing is provided empirically for the ER formulation.
• Oral Extended-Release Nifedipine Dosage:
  • Initial: 60 mg once daily.
  • Titrate gradually with close hemodynamic monitoring.
  • Reported dose range: 120 to 240 mg/day.
  • Some experts may start therapy at 30 mg once daily.

Nifedipine dose for the treatment of Raynaud phenomenon:

Oral Extended-Release Nifedipine:

• Initial: 30 mg once daily.
• If needed, may increase gradually, usually once every 4 weeks, but not more frequently than once every 7 to 10 days.
• Monitor blood pressure closely with each dose increase.
• Usual effective dose: 30 to 120 mg/day.

Immediate-Release Nifedipine (Short-term use in hospitalized patients with severe digital ischemia not yet receiving first-line therapy):

• Initial: 10 mg 3 times daily.
• Titrate by 10 mg increments every 4 to 6 hours if needed, up to 30 mg 3 times daily.
• Transition to an ER formulation for maintenance therapy.

Nifedipine treatment dose as a tocolytic agent:

Oral Immediate-Release Nifedipine:

• Initial: 20 to 30 mg as a loading dose.
• Followed by 10 to 20 mg every 3 to 8 hours for up to 48 hours.
• Maximum daily dose: 180 mg.

Dosing Considerations for Renal Impairment:

• Adult: No dosage adjustments provided in the manufacturer's labeling as it has not been studied.
• Pharmacokinetics of nifedipine are not significantly influenced by the degree of renal impairment.

Hemodialysis:

• Supplemental dose is not necessary.

Peritoneal Dialysis:

• Supplemental dose is not necessary.

Nifedipine dosage in children:

Nifedipine dose for the treatment of severe Hypertension:

• Limited data available; use under specialist supervision in the inpatient tertiary setting only after other alternatives are ineffective.
• Current pediatric guidelines do not recommend nifedipine for acute severe hypertension in children due to available safe and effective alternatives like hydralazine and isradipine.
• If nifedipine is necessary, administer inpatient where blood pressure and other parameters can be closely monitored.

Children and Adolescents Oral Immediate-Release Nifedipine Dosage:

• Initial: 0.04 to 0.25 mg/kg/dose.
• Maximum single dose: 10 mg.
• May repeat every 4 to 6 hours if needed.
• Monitor carefully.
• Maximum daily dose: 1 to 2 mg/kg/day.

Nifedipine dose for the chronic treatment of Hypertension:

Chronic Therapy for Hypertension in Children and Adolescents (Able to Swallow Whole Tablet):

• Limited data available; exercise caution.
• Oral Extended-Release Nifedipine:
  • Initial: 0.25 to 0.5 mg/kg/day once daily or divided into two doses every 12 hours.
  • Do not exceed the initial adult daily dose of 30 to 60 mg/day.
  • Titrate dose to effect.
  • Maximum daily dose:
    • Some centers recommend up to 3 mg/kg/day, up to 120 mg/day.
    • Higher maximum dose: Up to 3 mg/kg/day, up to 180 mg/day.
  • Note: Doses are usually titrated upward over 7 to 14 days; may increase over 3 days if clinically necessary.

Nifedipine (Procardia, Adalat) dose for the treatment of High-altitude pulmonary edema in children and adolescents:

• Limited data available; reserve nifedipine treatment for cases where oxygen and/or altitude descent show unsatisfactory response.

Oral Immediate-Release Nifedipine:

• 0.5 mg/kg/dose every 8 hours.
• Maximum dose: 20 mg/dose.

Oral Extended-Release Nifedipine (Preferred):

• 1.5 mg/kg/day given once daily or divided into two doses per day.
• Maximum dose: 40 mg/dose.
• Usual adult dose: 30 mg every 12 hours.

Pregnancy Risk Category: C

• Nifedipine can pass from a pregnant person to their baby through the placenta.
• Using nifedipine during pregnancy may lead to increased risks for the baby, such as perinatal asphyxia, cesarean delivery, prematurity, and slowed growth in the womb.
• If the pregnant person has chronic high blood pressure, there's a higher chance of birth defects, low birth weight, preterm birth, stillbirth, and neonatal death.
• The risks depend on how severe and how long the high blood pressure lasts.
• If treatment is needed for chronic high blood pressure during pregnancy, oral nifedipine is one of the preferred options.
• It's also recommended for managing sudden and severe high blood pressure in pregnant and postpartum people, including those with conditions like preeclampsia or eclampsia.
• Nifedipine has also been studied for treating premature labor, but it's only used for short periods (up to 48 hours) to delay birth and give time for steroid treatments.
• It shouldn't be used before the baby is able to survive outside the womb or when the risks to the baby or mother are higher than the risk of premature birth.
• However, nifedipine isn't effective for long-term treatment to delay premature labor.

Nifedipine use during breastfeeding:  

• Nifedipine can be found in breast milk, with levels ranging from 0.27% to 3.2% of the maternal dose when compared to the infant's therapeutic dose.
• Typically, breastfeeding is considered safe when the relative infant dose is less than 10%.
• Studies have shown that the relative infant dose of nifedipine is within this acceptable range.
• For example, after a mother took oral nifedipine following delivery, the estimated daily infant dose via breast milk was 8 mcg/kg/day.
• Nifedipine concentrations in breast milk can peak within an hour of maternal intake and have a half-life of around 3 hours.
• Case reports and series have shown that using nifedipine to treat Raynaud phenomenon in breastfeeding mothers didn't cause any adverse effects in their infants.
• However, the decision to continue breastfeeding while taking nifedipine should weigh the risks of infant exposure against the benefits of breastfeeding and the mother's need for treatment.
• The Academy of Breastfeeding Medicine recommends using nifedipine to treat Raynaud phenomenon of the nipple in breastfeeding mothers.

Nifedipine dose adjustment in renal disease:

Manufacturer's Labeling:

• No dosage adjustments are provided because it hasn't been studied.
• The way nifedipine works in the body isn't affected much by kidney problems, as only small amounts of the unchanged drug are found in urine.

Hemodialysis:

• People on hemodialysis don't need an extra dose of nifedipine.

Peritoneal Dialysis:

• People using peritoneal dialysis also don't need an extra dose of nifedipine.

Nifedipine dose adjustment in liver disease:

Manufacturer's Labeling:

• No specific dosage adjustments are provided because it hasn't been studied, but caution is advised.
• In patients with cirrhosis (liver disease), the body may clear nifedipine more slowly, leading to higher levels in the bloodstream.
• Close monitoring for adverse effects and toxicity is important, and dose adjustments may be necessary based on individual response and liver function.

Common Side Effects of Nifedipine:

• Cardiovascular:
  • Flushing
  • Peripheral Edema
• Central Nervous System:
  • Dizziness
  • Headache
• Gastrointestinal:
  • Heartburn
  • Nausea

Side Effects of Nifedipine (Uncommon):

• Cardiovascular:
  • Palpitations
  • Transient Hypotension
  • Cardiac Failure
• Central Nervous System:
  • Mood Changes
  • Nervousness
  • Fatigue
  • Chills
  • Disturbed Sleep
  • Equilibrium Disturbance
  • Jitteriness
  • Shakiness
• Dermatologic:
  • Dermatitis
  • Diaphoresis
  • Pruritus
  • Urticaria
• Gastrointestinal:
  • Gingival Hyperplasia
  • Sore Throat
  • Abdominal Cramps
  • Constipation
  • Diarrhea
  • Flatulence
• Genitourinary:
  • Sexual Difficulty
• Neuromuscular & Skeletal:
  • Muscle Cramps
  • Tremor
  • Weakness
  • Joint Stiffness
• Ophthalmic:
  • Blurred Vision
• Respiratory:
  • Cough
  • Nasal Congestion
  • Wheezing
  • Chest Congestion
  • Dyspnea
• Miscellaneous:
  • Fever
  • Inflammation

Contraindication to Nifedipine (Adalat, Procardia):

• Hypersensitivity to nifedipine or any component of the formulation.
• Considered contraindicated in patients with ST-elevation myocardial infarction (STEMI).
• Additional contraindications in Canadian labeling (not in US labeling):
  • Severe hypotension.
  • Cardiovascular shock.
  • Breastfeeding.
  • Pregnancy or women of childbearing potential.
• Extended release only:
  • Hypersensitivity to other dihydropyridine calcium antagonists.
  • Kock pouch (ileostomy after proctocolectomy).
  • Moderate or severe hepatic impairment.
  • Severe gastrointestinal obstructive disorders.
  • Concomitant use with rifampicin.

Warnings and precautions

Angina or MI

• When starting or adjusting the dose of dihydropyridine calcium channel blockers like nifedipine, there's a risk of more angina (chest pain) or heart attacks (MI).
• Reflex tachycardia, which is a sudden increase in heart rate, can happen and lead to more angina or heart attacks, especially in people with blocked heart arteries, especially if they're not also taking beta-blockers.
• For patients with unstable angina or a non-ST-elevation myocardial infarction (non-STEMI), it's not recommended to use immediate-release nifedipine unless they're also taking beta-blockers.

Syncope and hypotension:

• Symptomatic low blood pressure, sometimes leading to fainting, can rarely happen with nifedipine.
• It's important to lower blood pressure at a rate that's right for the patient's condition.
• Using immediate-release nifedipine, whether under the tongue or swallowed, for sudden high blood pressure situations isn't safe or effective.
• Serious problems like death, stroke, or heart attacks have been reported.
• Immediate-release nifedipine shouldn't be used to quickly lower blood pressure.
• There are guidelines available for using immediate-release nifedipine in emergencies during pregnancy or after giving birth.

Peripheral edema

• The most common side effect of nifedipine is swelling in the arms or legs, called peripheral edema.
• It usually happens within 2 to 3 weeks after starting treatment.

Aortic stenosis

• Use nifedipine very carefully in patients with severe aortic stenosis.
• It could decrease blood flow to the heart muscle, leading to a condition called myocardial ischemia.

Restrictions on GI:

• Be cautious when using extended-release nifedipine in patients with changes in their gastrointestinal (GI) anatomy, like severe narrowing, history of GI cancer, obstruction, bowel surgery, gastric bypass, or vertical banded gastroplasty.
• These conditions, along with problems in how the GI tract moves, can lead to the formation of bezoars, which are clumps of undigested material that can cause blockages.

Heart failure:

• The ACC/AHA guidelines for heart failure recommend avoiding the use of nifedipine in patients with heart failure because it hasn't shown to bring benefits and might even lead to worse outcomes.

Hepatic impairment:

• Be careful when using nifedipine in patients with liver problems.
• In people with cirrhosis (severe liver scarring), nifedipine can stay in the body longer, increasing the risk of side effects.
• Monitor closely for any signs of problems and consider adjusting the dose if needed.

Hypertrophic cardiomyopathy with outflow tract obstruction (HCM)

• Be cautious when using nifedipine in patients with hypertrophic cardiomyopathy (HCM) and outflow tract obstruction.
• Lowering the pressure against which the heart pumps (afterload) with nifedipine might make symptoms related to this condition worse.

Nifedipine: Drug Interaction

Note: Drug Interaction Categories:

• Risk Factor C: Monitor When Using Combination
• Risk Factor D: Consider Treatment Modification
• Risk Factor X: Avoid Concomitant Use

Risk Factor C (Monitor therapy)
Alcohol (Ethyl)	May raise NIFEdipine's serum concentration.
Alfuzosin	The hypotensive effects of blood pressure-lowering medications may be strengthened.
Alpha1-Blockers	The hypotensive effects of calcium channel blockers may be strengthened.
Amphetamines	May lessen the effectiveness of antihypertensive agents.
Antipsychotic Agents (Second Generation [Atypical])	Antipsychotic drugs' hypotensive effects may be enhanced by blood pressure-lowering medications (Second Generation [Atypical]).
Aprepitant	May elevate CYP3A4 substrates' serum concentration (High risk with Inhibitors).
Atosiban	Calcium channel blockers may intensify Atosiban's harmful or hazardous effects. Particularly, pulmonary edoema and/or dyspnea may be at higher risk.
Barbiturates	Calcium Channel Blockers' metabolic rate might be increased. Management: Keep an eye out for any diminished therapeutic effects of barbiturate medication when concurrently using calcium channel blockers. There may need to be dose modifications with calcium channel blockers. The concurrent use of phenobarbital and nimodipine is not recommended.
Barbiturates	The hypotensive effects of blood pressure-lowering medications may be strengthened.
Benperidol	The hypotensive effects of blood pressure-lowering medications may be strengthened.
Beta-Blockers	Beta-Blockers' hypotensive effects may be strengthened with NIFEdipine. The detrimental inotropic impact of beta-blockers may be amplified by NIFEdipine.
Bosentan	May lower CYP3A4 substrates' serum concentration (High risk with Inhibitors).
Brigatinib	May lessen the effectiveness of antihypertensive agents. Antihypertensive Agents' bradycardic action may be strengthened by brutinib.
Brimonidine (Topical	The hypotensive effects of blood pressure-lowering medications may be strengthened.
Calcium Channel Blockers (Nondihydropyridine)	Dihydropyridine, a calcium channel blocker, may increase the hypotensive effects of calcium channel blockers (Nondihydropyridine). Calcium Channel Blockers (Nondihydropyridine) may cause an increase in serum calcium channel blocker concentration (Dihydropyridine).
Calcium Salts	May diminish the therapeutic effect of Calcium Channel Blockers.
Cisapride	May increase the serum concentration of NIFEdipine. Reported with sustained release nifedipine product.
Clofazimine	May elevate CYP3A4 substrates' serum concentration (High risk with Inhibitors).
Clopidogrel	Calcium channel blockers may reduce Clopidogrel's therapeutic efficacy.
CycloSPORINE (Systemic)	The serum concentration of CycloSPORINE may rise when Calcium Channel Blockers (Dihydropyridine) are taken (Systemic). Calcium Channel Blockers' serum levels may rise when CycloSPORINE (Systemic) is used (Dihydropyridine).
CYP3A4 Inducers (Moderate)	May lower CYP3A4 substrates' serum concentration (High risk with Inhibitors).
CYP3A4 Inhibitors (Moderate)	May lower CYP3A4 substrates' serum concentration (High risk with Inhibitors).
Dapoxetine	The hypotensive effects of calcium channel blockers may be strengthened.
Deferasirox	May lower CYP3A4 substrates' serum concentration (High risk with Inhibitors).
Dexmethylphenidate	May lessen the effectiveness of antihypertensive agents.
Diazoxide	The hypotensive effects of blood pressure-lowering medications may be strengthened.
Digoxin	Digoxin's serum levels may rise in response to NIFEdipine.
DULoxetine	The hypotensive impact of DULoxetine may be enhanced by blood pressure lowering medications.
Duvelisib	May enhance CYP3A4 substrates' serum concentration (High risk with Inhibitors).
Efavirenz	The hypotensive effects of calcium channel blockers may become weaker.
Erdafitinib	May lower CYP3A4 substrates' serum concentration (High risk with Inhibitors).
Erdafitinib	May enhance CYP3A4 substrates' serum concentration (High risk with Inhibitors).
Fluconazole	The hypotensive effects of calcium channel blockers may be strengthened.
FLUoxetine	May raise NIFEdipine's serum concentration.
Fosaprepitant	May enhance CYP3A4 substrates' serum concentration (High risk with Inhibitors).
Fosnetupitant	May enhance CYP3A4 substrates' serum concentration (High risk with Inhibitors).
Herbs (Hypertensive Properties)	May lessen the effectiveness of antihypertensive agents.
Herbs (Hypotensive Properties)	The hypotensive effects of blood pressure-lowering medications may be strengthened.
Hypotension-Associated Agents	The hypotensive action of hypotension-associated agents may be strengthened by blood pressure lowering medications.
Ivosidenib	May lower CYP3A4 substrates' serum concentration (High risk with Inhibitors).
Larotrectinib	May enhance CYP3A4 substrates' serum concentration (High risk with Inhibitors).
Levodopa-Containing Products	Levodopa-Containing Products' hypotensive effects may be strengthened by blood pressure-lowering medications.
Lormetazepam	The hypotensive effects of blood pressure-lowering medications may be strengthened.
Magnesium Salts	Calcium channel blockers might make magnesium salts more harmful or poisonous. Calcium Channel Blockers' hypotensive effects may be strengthened by magnesium salts.
Melatonin	The hypotensive effects of calcium channel blockers may become weak.
Methylphenidate	May lessen the effectiveness of antihypertensive agents.
Molsidomine	The hypotensive effects of blood pressure-lowering medications may be strengthened.
Naftopidil	The hypotensive effects of blood pressure-lowering medications may be strengthened.
Netupitant	May enhance CYP3A4 substrates' serum concentration (High risk with Inhibitors).
Neuromuscular-Blocking Agents (Nondepolarizing)	The neuromuscular-blocking impact of neuromuscular-blocking agents may be enhanced by calcium channel blockers (Nondepolarizing).
Nicergoline	The hypotensive effects of blood pressure-lowering medications may be strengthened.
Nicorandil	The hypotensive effects of blood pressure-lowering medications may be strengthened.
Nitroprusside	Blood Pressure Lowering Agents may enhance the hypotensive effect of Nitroprusside.
Palbociclib	May enhance CYP3A4 substrates' serum concentration (High risk with Inhibitors).
Pentoxifylline	The hypotensive effects of blood pressure-lowering medications may be strengthened.
Pholcodine	Pholcodine's hypotensive impact may be strengthened by blood pressure lowering medications.
Phosphodiesterase 5 Inhibitors	The hypotensive effects of blood pressure-lowering medications may be strengthened.
Prostacyclin Analogues	The hypotensive effects of blood pressure-lowering medications may be strengthened.
Quinagolide	The hypotensive effects of blood pressure-lowering medications may be strengthened.
QuiNIDine	The serum concentration of QuiNIDine may be lowered by calcium channel blockers (Dihydropyridine). The serum concentration of QuiNIDine may rise in response to calcium channel blockers (Dihydropyridine). Calcium Channel Blockers' serum levels may rise in response to quinine (Dihydropyridine).
Sarilumab	May lower CYP3A4 substrates' serum concentration (High risk with Inhibitors).
Siltuximab	May lower CYP3A4 substrates' serum concentration (High risk with Inhibitors).
Simeprevir	May enhance CYP3A4 substrates' serum concentration (High risk with Inhibitors).
Tacrolimus (Systemic)	Tacrolimus serum levels may rise when Calcium Channel Blockers (Dihydropyridine) are used (Systemic).
Tocilizumab	May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers).
VinCRIStine	The serum levels of vincristine may rise when taking NIFEdipine.
VinCRIStine (Liposomal)	VinCRIStine serum levels may rise in response to NIFEdipine (Liposomal).
Yohimbine	May lessen the effectiveness of antihypertensive agents.
Risk Factor D (Consider therapy modification)
Amifostine	Amifostine's hypotensive impact may be strengthened by blood pressure lowering medications. Treatment: Blood pressure-lowering drugs need to be avoided for 24 hours before amifostine is administered when used at chemotherapeutic doses. Amifostine should not be given if blood pressure lowering treatment cannot be stopped.
Antifungal Agents (Azole Derivatives, Systemic)	Calcium Channel Blockers' harmful or toxic effects could be exacerbated. In particular, itraconazole may make verapamil or diltiazem's unfavourable inotropic effects worse. Calcium Channel Blockers' metabolism may be slowed down by antifungal agents (systemic azole derivatives). Fluconazole and isavuconazonium, which are covered in different monographs, probably have less powerful effects than those of other azoles. Treatment: Itraconazole should not be used concurrently with felodipine or nisoldipine. With any such combination, regular monitoring is advised; calcium channel blocker dose decreases might be necessary. Fluconazole and isavuconazonium sulphate are exceptions.
Cimetidine	Calcium Channel Blockers' serum levels can rise. Management: Take cimetidine substitutes into consideration. If there is no suitable substitute, watch for increased calcium channel blocker effects after starting or increasing the dosage of cimetidine and decreased effects after stopping or decreasing the dosage.
Cladribine	The serum content of Cladribine may rise in response to inhibitors of equilibrative nucleoside (ENT1) and concentrated nucleoside (CNT3) transport proteins. Management: Whenever possible, avoid using ENT1 or CNT3 inhibitors concurrently during the 4 to 5 day oral cladribine therapy cycles. If coupled, think about separating the date of delivery and reducing the amount of an ENT1 or CNT3 inhibitor.
CYP3A4 Inhibitors (Strong)	May slow down CYP3A4 substrate metabolism (High risk with Inhibitors).
Dabrafenib	May lower the serum level of CYP3A4 substrates (High risk with Inducers). Management: When possible, look for substitutes for the CYP3A4 substrate. If concurrent therapy cannot be avoided, pay special attention to the substrate's clinical consequences (particularly therapeutic effects).
Lorlatinib	May lower the serum level of CYP3A4 substrates (High risk with Inducers). Management: Avoid taking lorlatinib at the same time as any CYP3A4 substrates for which even a small drop in serum levels of the substrate could result in therapeutic failure and negative clinical outcomes.
Macrolide Antibiotics	Calcium Channel Blockers' metabolic rate might be decreased. Use a noninteracting macrolide as a possible management strategy. The Canadian labelling for felodipine expressly advises against using it in conjunction with clarithromycin. Exceptions: Fidaxomicin, Roxithromycin, Spiramycin, and systemic azithromycin.
MiFEPRIStone	May elevate CYP3A4 substrates' serum concentration (High risk with Inhibitors). Management: During and two weeks after mifepristone treatment, reduce doses of CYP3A4 substrates and keep an eye out for elevated amounts or toxicity. Fentanyl, pimozide, quinidine, sirolimus, and tacrolimus should all be avoided. Cyclosporine should also be avoided.
Nafcillin	May lower the level of NIFEdipine in the serum.
Obinutuzumab	The hypotensive effects of blood pressure-lowering medications may be strengthened. Management: Take into account temporarily stopping blood pressure-lowering drugs 12 hours before the start of the obinutuzumab infusion and keeping them off until 1 hour after the infusion is finished.
Rifamycin Derivatives	Calcium Channel Blockers' serum concentration can drop. This predominantly affects calcium channel blockers used orally. Management: Using rifampin with certain calcium channel blockers is not advised according to the labelling in the US and Canada. Look up the relevant labelling.
Sincalide	The therapeutic benefit of Sincalide may be reduced by medications that affect gallbladder function. Prior to using sincalide to induce gallbladder contraction, you should think about stopping any medications that can impair gallbladder motility.
Stiripentol	May elevate CYP3A4 substrates' serum concentration (High risk with Inhibitors). Management: Due to the increased potential for side effects and toxicity, stiripentol should not be used with CYP3A4 substrates that are thought to have a narrow therapeutic index. Use of stiripentol with any CYP3A4 substrate necessitates closer observation.
Risk Factor X (Avoid combination)
Bromperidol	The hypotensive impact of bromperidol may be enhanced by blood pressure lowering medications. Blood Pressure Lowering Agents' hypotensive effects may be lessened by bromperidol.
Conivaptan	May elevate CYP3A4 substrates' serum concentration (High risk with Inhibitors).
CYP3A4 Inducers (Strong)	May lower the level of NIFEdipine in the serum.
Fusidic Acid (Systemic)	May elevate CYP3A4 substrates' serum concentration (High risk with Inhibitors).
Grapefruit Juice	May lower the level of NIFEdipine in the serum.
Idelalisib	May elevate CYP3A4 substrates' serum concentration (High risk with Inhibitors).
Phenytoin	Phenytoin's serum levels may rise in response to NIFEdipine. The blood levels of NIFEdipine may drop when phenytoin is taken.
St John's Wort	May lower the level of NIFEdipine in the serum.

Monitoring parameters:

• Heart Rate:
  • Check how fast the heart is beating.
• Blood Pressure:
  • Measure the force of blood against artery walls.
• Signs and Symptoms of Heart Failure:
  • Watch for signs like shortness of breath, fatigue, and swelling.
• Peripheral Edema:
  • Look out for swelling in the legs or arms.

Hypertension:

• Confirmed Hypertension with Known Cardiovascular Disease (CVD) or High ASCVD Risk:
  • Target blood pressure should be less than 130/80 mm Hg.
• Confirmed Hypertension without Increased ASCVD Risk:
  • Target blood pressure below 130/80 mm Hg might be reasonable.

Diabetes and Hypertension:

• Patients 18 to 65 Years without ASCVD and Low ASCVD Risk:
  • Target blood pressure less than 140/90 mm Hg is recommended.
• Patients 18 to 65 Years with Known ASCVD or High ASCVD Risk:
  • Target blood pressure below 130/80 mm Hg may be appropriate if it's safe.
• Patients Over 65 Years Old:
  • Target blood pressure below 140/90 mm Hg is recommended for most.
  • For those in poor health, aim for less than 150/90 mm Hg.

How to administer Nifedipine (Procardia, Adalat)?

Oral Administration:

• Immediate Release:
  • Can be taken with or without food.
• Extended Release:
  • Swallow tablets whole; do not crush, split, or chew.
  • For Adalat CC, Afeditab CR:
    • Take on an empty stomach (per manufacturer's recommendation).
  • Other extended-release products may not have the same recommendation; check product labeling for specific instructions.

Nifedipine (Procardia, Adalat) Mechanism of action:

• Nifedipine works by blocking calcium ions from entering specific areas of muscle cells in blood vessels and the heart during electrical stimulation.
• This blocking action causes relaxation of smooth muscles in the coronary arteries, leading to widening of these vessels, which helps increase blood flow to the heart muscle, especially in patients with vasospastic angina.
• Additionally, nifedipine decreases resistance in peripheral blood vessels, resulting in lower blood pressure.

Onset of Action:

• Immediate Release:
  • Takes around 20 minutes to start working.

Protein Binding:

• Concentration Dependent:
  • Typically binds to proteins in the blood between 92% to 98%.
  • Protein binding might be significantly lower in patients with kidney or liver problems.

Metabolism:

• Hepatic Metabolism:
  • Processed by the liver through an enzyme called CYP3A4 into inactive forms.

Bioavailability:

• Capsule:
  • Between 40% to 77%.
• Extended Release (ER):
  • Between 65% to 89% compared to immediate-release capsules.
  • Bioavailability increases in people with significant liver disease.

Half-life Elimination:

• Adults:
  • Healthy: 2 to 5 hours.
• Cirrhosis:
  • 7 hours.
• Elderly:
  • 7 hours (extended-release tablet).

Excretion:

• Routes:
  • Mostly through urine (60% to 80%) as inactive forms.
  • Some through feces.

Nifedipine Brand Names (International):

• Adalat CC
• Afeditab CR
• Nifedical XL
• Procardia
• Procardia XL
• Adalat XL
• APO-Nifed PA
• DOM-NIFEdipine
• MYLAN-NIFEdipine
• PMS-NIFEdipine
• PMSNIFEdipine ER Adalat
• Adalat 10
• Adalat 20
• Adalat CC
• Adalat CR
• Adalat Crono
• Adalat GITS
• Adalat GITS 30
• Adalat L
• Adalat LA
• Adalat LP
• Adalat Oros
• Adalat Retard
• Adalat XL
• Adalate
• Addos XR
• Adefin
• Adefin XL
• Adifen SR
• Adipine XL
• Alonix-S
• Altapres
• Ampine
• Aprical
• Atanaal Softcap
• Calcibloc
• Calcibloc OD
• Calcicor
• Calcigard
• Calcigard Retard
• Cardifen
• Cardiiopine
• Chronadalate LP
• Citilat
• Coracten
• Coral
• Cordaflex
• Cordilat
• Cordipen
• Cordipen Retard
• Cordipin
• Cordipin Retard
• Cordipin XL
• Corinfar
• Corinfar Retard
• Corotrend
• Depin
• Depin-E Retard
• Dignokonstant
• Dipinkor
• Duranifin
• Ecodipin
• Epilat
• Fenamon
• Glopir
• Hexadilat
• Huma-Nifedin
• Hypan
• Jutadilat
• Kin Ran
• Myogard
• Nedipin
• Nelapine
• Nepin SR
• Nicardia
• Nicardia CD
• Nicardia Retard
• Nicardia XL
• Nidipin
• Nifa
• Nifadil
• Nifangin
• Nifar
• Nifar-GB
• Nifdemin
• Nifebene
• Nifecap
• Nifecard
• Nifecard XL
• Nifecor
• Nifedepat
• Nifedicor
• Nifedigel
• NIfedilat
• Nifedilong
• Nifedin
• Nifedine
• Nifedipin
• Nifedipin AL
• Nifedipin Pharmavit
• Nifedipin Stada
• Nifedipin-ratiopharm
• Nifedipresc MR
• Nifedix SR
• Nifehexal
• Nifehexal 30 LA
• Nifelan
• Nifelat
• Nifelat Q
• Nifelat-Q
• Nifensar
• Nifensar Retard
• Niferon CR
• Nifeslow
• Nifestad
• Nifezzard
• Nificard
• Nifin
• Nifipen
• Nipen
• Noviken LP
• Nyefax Retard
• Odipin
• Orix
• Osmo-Adalat
• Pidilat
• Pressolat
• Sepamit
• Servidipine
• Slow-Nifine
• Unidipin
• Vasonipine
• Zenusin

Nifedipine Brand Names in Pakistan:

Nifedipine Tablets 10 mg
Nifelate	Siza International (Pvt) Ltd.

 

Nifedipine Tablets 20 mg
Adalat Retard	Bayer Health Care
Anifed	Tread Pharmaceuticals Pvt Ltd
Nifecard Retard	Novartis Pharma (Pak) Ltd
Nifed	Unimark Pharmaceuticals
Nifedicor	Scharper Pharmaceuticals (Pvt) Ltd.

 

Nifedipine Tablets 30 mg
Adalat La	Bayer Health Care
Adalat-Cc	Bayer Health Care
Nifecard Xl	Novartis Pharma (Pak) Ltd
Nifedil-Xl	Zafa Pharmaceutical Laboratories (Pvt) Ltd.
Nifine C.C	Tread Pharmaceuticals Pvt Ltd

 

Nifedipine Tablets 60 mg
Adalat La	Bayer Health Care
Adalat-Cc	Bayer Health Care

 

Nifedipine SR Tablets 20 mg
Anifed	Tread Pharmaceuticals Pvt Ltd

 

Nifedipine Capsules 10 mg
Adalat	Bayer Health Care
Adipen	Lisko Pakistan (Pvt) Ltd
Caranta	Akhai Pharmaceuticals.
Nifedil	Zafa Pharmaceutical Laboratories (Pvt) Ltd.
Nifedil S.G	Zafa Pharmaceutical Laboratories (Pvt) Ltd.
Ronian	S. Ejazuddin & Company
Vasculine	Geofman Pharmaceuticals

 

Nifedipine Capsules Sr 20 Mg
Cardipine	Phar-Man Laboratories