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 sublingually is not recommended due to safety concerns.
• Extended-release (ER) tablets and immediate-release capsules, which are commonly administered three times daily, are two dosage types (prescribed once daily).
• When changing from an immediate-release to an extended-release version, the dosage is unaffected.

Nifedipine dose for the treatment of Anal fissure:

Note:

In addition to supporting measures, topical application acts as a local vasodilator. Ointment and gel must be made by a licenced compounding facility because they are not commercially available.

• Intra-anal: 0.2% to 0.3% ointment or gel should be applied on or around fissures 2 to 4 times daily for one month.

Nifedipine treatment dose for the treatment of Angina pectoris:

• Chronic stable angina (alternative agent):

Note:

• Beta-blocker medication may be supplemented with a long-acting dihydropyridine calcium channel blocker, such as nifedipine, if symptoms are not managed.
• If beta-blockers are contraindicated, extended-release nifedipine may be used as an alternate treatment.
• The use of immediate-release nifedipine (oral/sublingual) is not typically recommended due to increased side effects such reflex tachycardia and hypotension, especially when a beta-blocker is not present.

• Extended-release nifedipine tablets:

  • Initial dosage is either 30 mg or 60 mg orally once daily.
  • Over the course of 7–14 days, the dose should be increased in accordance with an effective antianginal dose.
  • Rarely are doses greater than 90 mg per day necessary.
  • The daily oral dose cap is 120 mg.

• Vasospastic angina:

Note: May be used as a single agent or concurrently with nitrates.

• Extended-release:

  • The dose is the same as for chronic stable angina.

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

• For the prevention of high-altitude pulmonary edema:

Note: In addition to a steady increase, in high-risk individuals (e.g. history of high altitude pulmonary edoema or other predisposing factors).

• Extended-release:

  • 30 mg orally, starting 24 hours prior to the ascent, every 12 hours.
  • Five days should pass after reaching the highest altitude before stopping.
  • When there is a high danger, the course of treatment may last longer than five days (eg, descent impossible).

• For the Treatment of high-altitude pulmonary edema:

Note: Adjunctive therapy to nonpharmacologic interventions like oxygen delivery, a portable hyperbaric chamber, or a progressive fall to lower altitude, or as a sole agent if nonpharmacologic interventions are not accessible.

• Extended-release:

  • Every 12 hours, take 30 mg orally.

Nifedipine dose for the treatment of Hypertension:

Note:

When blood pressure is more than 20/10 mmHg above target, it can be used in conjunction with another medication, such as an ACE inhibitor, angiotensin receptor blocker, or thiazide diuretic, as the first line of treatment. It can be used as a single agent for patients who are more than 20/10 mm Hg above target, although many patients will eventually require combination therapy.

•  Extended-release formulation:

  • The first dose is either 30 or 60 mg taken orally once per day.
  • Every 7 to 14 days, the dose should be raised based on response and tolerability.
  • The usual dosage range is 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:

  • If the goal blood pressure is not reached, take a second dose of 30 mg orally one to two hours later.
  • After the second dose, another class of medications should be examined if the systolic and diastolic blood pressure levels are still elevated.

• Immediate-release (alternative agent):

Note:

Usually saved for situations where there is no intravenous access. Immediate-release medications are sometimes discouraged by specialists since they may cause some women's blood pressure to decrease. Don't sublingually or puncture the capsule.

• • 10 mg orally once at first with foetal heart rate monitoring.
  • Depending on the initial reaction, a second dose of 10 or 20 mg per mouth should be administered if either the systolic or diastolic blood pressure remains above target at 20 minutes.
  • Give a second dose of 10 or 20 mg, depending on the reaction from the first dose, if blood pressure is still above target after 40 minutes.
  • A different class of drugs should be taken into consideration if the goal blood pressure is not reached after three doses.

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

Note:

It is only advised for carefully chosen individuals with group 1 pulmonary arterial hypertension who tested positive for vasodilators and are being treated by a pulmonary hypertension expert. A 12-hour sustained-release version that is unavailable in the US is recommended by European guidelines. In the case of the extended-release formulation, dosing is offered empirically.

• Extended-release formulation:

  • 60 mg per oral every 2 hours.
  • Titrate gradually while closely monitoring your hemodynamic state.
  • A daily oral dosage of between 120 and 240 mg has been observed.
  • Some medical professionals start treatment with 30 mg orally once daily.

Nifedipine dose for the treatment of Raynaud phenomenon:

• Extended-release:

  • The initial dose of  30 mg per oral once daily
  • The dose may be increased gradually once every month if required, but not more frequently than once every 7 to 10 days.
  • Close BP monitoring with each dose increase should be done
  • The usual effective dose: 30 to 120 mg/day.

• Immediate release:

Note:

Only for short-term use in hospitalised patients with severe digital ischemia who have not received first-line therapy and are under close observation.

• • To transition to an extended-release formulation for maintenance therapy, the initial dose of 10 mg per mouth thrice daily was titrated up to 30 mg thrice daily if necessary by 10 mg increments every 4 to 6 hours.

Nifedipine treatment dose as a tocolytic agent:

• Immediate-release:

  • 20 to 30 mg as a loading dose at first, then 10 to 20 mg every three to eight hours for up to 48 hours.
  • The daily dosing cap is 180 mg.

Nifedipine dosage in children:

Nifedipine dose for the treatment of severe Hypertension:

Note:

It should only be used for paediatric hypertension under the guidance of a specialist in an inpatient tertiary setting and only when other medications have failed.

Since there are other safe/effective medications like hydralazine and isradipine available for the management of acute severe hypertension, current paediatric blood pressure guidelines do not prescribe nifedipine.

• Immediate-release tablets in Children and Adolescents:

  • 0.04 to 0.25 mg/kg orally.
  • 10 mg/dose is the maximum single dose.
  • If necessary, the dose may be given again every 4 to 6 hours up to a daily dose maximum of 1 to 2 mg/kg/day with careful monitoring.

Nifedipine dose for the chronic treatment of Hypertension:

• Children and Adolescents who are able to swallow the whole tablet:

  • Extended-release:

    • The initial dose of 0.25 to 0.5 mg/kg given either once daily or twice every 12 hours.
    • Adults' starting daily doses shouldn't be higher than 30 to 60 mg/day when titrated to an effective level.
    • The daily dose ranges from 3 mg/kg up to 120 mg.
    • Some hospitals set their maximum dose higher: Up to 180 mg/kg/day

Note: Typically, doses are increased over one to two weeks, although they may also be increased over three days if a clinical need arises.

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

Note: An inadequate response to oxygen and/or an altitude drop should be treated with nifedipine.

• Immediate-release formulation:

  • every eight hours, oral dose of 5 mg/kg
  • 20 mg is the maximum dose per dose.

• Extended-release (preferred):

  • 5 mg/kg/day per oral, administered either once daily or twice daily
  • The maximum dose per dose is 40 mg.
  • Adults typically take 30 mg every 12 hours.

Pregnancy Risk Category: C

• Nifedipine can cross the placenta.
• It can increase perinatal asphyxia and C-section, prematurity, intrauterine growth retardation, and perinatal asphyxia.
• The actual risk to the foetus or newborn relies on how severe and persistent the mother's hypertension is.
• The risk of gestational diabetes and associated problems including MI, preeclampsia, or stroke may rise if uncontrolled hypertension is present.
• There is also oral nifedipine, one of the most popular therapies for chronic prenatal hypertension.
• Oral immediate-release nifedipine may also be suggested for the treatment of severe, acute-onset hypertension in pregnant or postpartum women (including those with preeclampsia and eclampsia).
• Preterm labor can be treated with Nifedipine.
• Tocolytics can be used to extend pregnancy for a brief period of time (48 hours) so that antenatal steroids can be given.
• When the harm to the mother or foetus is higher than the risk of preterm birth, they shouldn't be given before foetal viability.
• For the maintenance of tocolytic treatment, Nifedipine will not be effective.

Nifedipine use during breastfeeding:  

• Breast milk contains Nifedipine.
• According to the manufacturer the decision to continue breastfeeding while on therapy is based on the risks of infant exposure/the benefits to breastfeeding and the benefits to the mother.
• Nifedipine should be used to treat the Raynaud phenomenon of the nipple in nursing moms, according to the Academy of Breastfeeding Medicine.

Nifedipine dose adjustment in renal disease:

• The manufacturer's labelling does not mention dosage modifications (has not been studied).
• The degree of renal impairment has no discernible impact on the pharmacokinetics of nifedipine (only trace amounts of unchanged drug are found in urine).

Hemodialysis and peritoneal dialysis:

• The additional dose is not required.

Nifedipine dose adjustment in liver disease:

• The manufacturer's labelling does not mention dosage modifications (has not been studied).
• Take care when using.
• Cirrhosis decreases nifedipine clearance, which could increase systemic exposure.
• It is important to closely monitor for side effects and toxicity and to change doses as necessary.

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):

• Other contraindications include hypersensitivity to other dihydropyridine calcium antagonists or concurrent treatment with rifampicin, as well as hypersensitivity to nifedipine or any component of the formulation.

Not recommended for patients suffering from ST-elevation myocardial Infarction.

• Heart attack/ severe hypotension

Notice: Nifedipine is advised to be used as a preferred medication to treat maternal hypertension, according to SOGC and ACOG guidelines (Extended release only).

• Kock pouch (ileostomy following a proctocolectomy).
• hepatic impairment that is moderate to severe, severe intestinal obstruction diseases.

Warnings and precautions

• Angina or MI

  • Reflex tachycardia can occur when patients have dihydropyridine calciumchannel blockers. This is especially true if there are no concurrent beta-blockers.
  • Patients with unstable angina/nonST elevation myocardial injury should not be prescribed immediate-release nifedipine, except in combination with beta-blockade

• Syncope and hypotension:

  • It is rare to have hypotension symptoms with or without syncope. 
  • In acute blood pressure reduction, it is best to avoid immediate-release nifedipine.
  • It is essential to keep the patient's blood pressure at a level that is suitable for their needs given their clinical condition.
  • Immediate-release nifedipine can result in severe adverse events in hypertensive patients, including mortality, cerebrovascular infarction, stroke, syncope, hypotension, acute myocardial injury, and foetal distress.
  • There are rules about when to treat serious problems in expectant or postpartum moms with immediate-release nifedipine.

• Peripheral edema

  • The most frequent adverse effect within the first two to three weeks of medication is peripheral edoema.

• Aortic stenosis

  • Nifedipine may cause aortic constriction and myocardial infarction through decreasing coronary perfusion.

• Restrictions on GI:

  • Extended-release nifedipine can cause bezoar formation when there are alterations to the gastrointestinal anatomy (e.g., severe GI narrowing, GI Malignancy, obstruction, bowel resection), and underlying hypomotility disorders.

• Heart failure:

  • According to the ACC/AHA guidelines for heart failure, patients with heart disease should not use calcium channel blockers.
  • This is because they are likely to have worse outcomes and/or no benefit.

• Hypertrophic cardiomyopathy with outflow tract obstruction (HCM)

  • Patients with hypertrophic cardiomyopathy or outflow tract obstruction should be cautious. Reduced afterload could worsen the symptoms.

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:

These include pulse, Blood pressure, signs, and symptoms of heart failure, and peripheral edema.

Hypertension:

The 2017 National Institutes of Health Guideline for the Prevention, Detection, Evaluation, and Management of High Blood Pressure in Adults

Confirmed hypertension and known CVD (cardiovascular disease) or 10-year atherosclerotic cardiovascular disease (ASCVD) risk ≥10%:

• Target blood pressure <130/80 mm Hg is recommended

Confirmed hypertension without markers of increased ASCVD risk:

• Target blood pressure <130/80 mm Hg may be reasonable

Diabetes and hypertension:

• Patients 18 to 65 years of age, without ASCVD, and 10-year ASCVD risk <15%:

  • Target blood pressure <140/90 mm Hg is recommended

• Patients 18 to 65 years of age and known ASCVD or 10-year ASCVD risk >15%:

  • Target blood pressure <130/80 mm Hg may be appropriate if it can be safely attained

• Patients >65 years of age (healthy or complex/intermediate health):

  • Target blood pressure <140/90 mm Hg is recommended

• Patients >65 years of age (very complex/poor health):

  • Target blood pressure <150/90 mm Hg is recommended

How to administer Nifedipine (Procardia, Adalat)?

Immediate-release formulation:

• In general, it may be given orally with or without food.

Extended-release formulation:

• Tablets should be swallowed whole without crushing, splitting, or chewing.

Adalat CC, Afeditab CR:

• Administer on an empty stomach (per manufacturer).
• Other extended-release products may not have this recommendation.
• Consult product labeling.

Nifedipine (Procardia, Adalat) Mechanism of action:

• Nifedipine prevents calcium ions from entering the "slow channel" or particular voltage-sensitive regions of vascular smooth muscles and myocardium during depolarization.
• This causes the smooth muscle in the heart to relax and the blood vessels in the heart to widen.
• Vasospastic patients have more myocardial oxygen supply and lower peripheral resistance, which lowers arterial blood pressure.

The onset of action of the Immediate-release tablets is about 20 minutes

Protein binding (concentration-dependent):

• 92% to 98%.

Note: Protein-binding may be significantly decreased in patients with renal or hepatic impairment.

Metabolism:

• Hepatic via CYP3A4 to inactive metabolites.

Bioavailability:

• Capsule: 40% to 77%;
• Extended-release: 65% to 89% relative to immediate-release capsules;
• The bioavailability is increased with significant hepatic disease

Half-life elimination in healthy adults: 2 to 5 hours, in cirrhosis: 7 hours, and in the elderly: 7 hours (extended-release tablet)

Excretion:

• Urine (60% to 80% as inactive metabolites); 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