Adalat 20mg Capsules
It is used to treat some types of chest pain (angina).It may be given to you for other reasons. Talk with the doctor.
Drug Class
Antihypertensive, Antianginal
Pharmacologic Class
Calcium Channel Blocker (Dihydropyridine)
Pregnancy Category
Category C
FDA Approved
Dec 1981
DEA Schedule
Not Controlled
Overview
What is this medicine?
Nifedipine is a medicine that helps relax blood vessels, which lowers blood pressure and can help with chest pain (angina). It works by blocking calcium from entering certain cells in your heart and blood vessels.
How to Use This Medicine
Taking Your Medication Correctly
To get the most benefit from your medication, it's essential to take it exactly as directed by your doctor. Carefully read all the information provided with your prescription, and follow the instructions closely. When taking your medication, swallow the tablet whole - do not chew, break, or crush it.
Continue taking your medication as prescribed by your doctor or healthcare provider, even if you start to feel better. It's crucial not to stop taking your medication suddenly without consulting your doctor, as this may increase your risk of side effects. If you need to stop taking your medication, your doctor will advise you on how to gradually discontinue it to minimize potential side effects.
Storing and Disposing of Your Medication
To maintain the effectiveness and safety of your medication, store it at room temperature, protected from light, and in a dry place. Avoid storing your medication in a bathroom. Keep all medications in a secure location, out of the reach of children and pets.
When disposing of unused or expired medication, do not flush it down the toilet or pour it down the drain unless instructed to do so by your pharmacist or healthcare provider. Instead, check with your pharmacist for guidance on the best disposal method. You may also want to explore local drug take-back programs for safe and responsible disposal.
What to Do If You Miss a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses to make up for the missed one.
To get the most benefit from your medication, it's essential to take it exactly as directed by your doctor. Carefully read all the information provided with your prescription, and follow the instructions closely. When taking your medication, swallow the tablet whole - do not chew, break, or crush it.
Continue taking your medication as prescribed by your doctor or healthcare provider, even if you start to feel better. It's crucial not to stop taking your medication suddenly without consulting your doctor, as this may increase your risk of side effects. If you need to stop taking your medication, your doctor will advise you on how to gradually discontinue it to minimize potential side effects.
Storing and Disposing of Your Medication
To maintain the effectiveness and safety of your medication, store it at room temperature, protected from light, and in a dry place. Avoid storing your medication in a bathroom. Keep all medications in a secure location, out of the reach of children and pets.
When disposing of unused or expired medication, do not flush it down the toilet or pour it down the drain unless instructed to do so by your pharmacist or healthcare provider. Instead, check with your pharmacist for guidance on the best disposal method. You may also want to explore local drug take-back programs for safe and responsible disposal.
What to Do If You Miss a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses to make up for the missed one.
Lifestyle & Tips
- Take exactly as prescribed; do not crush, chew, or break capsules.
- Avoid grapefruit and grapefruit juice while taking this medication, as it can increase the amount of nifedipine in your body and lead to side effects.
- Limit alcohol consumption, as it can increase dizziness and lower blood pressure too much.
- Stand up slowly from a sitting or lying position to avoid dizziness or fainting.
- Maintain a healthy diet, regular exercise, and limit sodium intake as advised by your doctor.
- Report any new or worsening swelling in your ankles or feet.
Available Forms & Alternatives
Available Strengths:
Generic Alternatives:
Dosing & Administration
Adult Dosing
Standard Dose:
10-30 mg orally three times daily (TID)
Dose Range:
10 - 30 mg
Condition-Specific Dosing:
angina:
Initial: 10 mg TID. Titrate as needed, typically 10-30 mg TID. Max: 180 mg/day.
hypertension:
Initial: 10 mg TID. Titrate as needed, typically 10-30 mg TID. Max: 180 mg/day.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established for routine use; limited data for hypertensive emergencies (off-label, typically 0.25-0.5 mg/kg/dose, max 10 mg/dose)
Adolescent:
Not established for routine use; limited data for hypertensive emergencies (off-label, typically 0.25-0.5 mg/kg/dose, max 10 mg/dose)
Dose Adjustments
Renal Impairment:
Mild:
No adjustment typically needed
Moderate:
No adjustment typically needed
Severe:
No adjustment typically needed
Dialysis:
Not dialyzable; no supplemental dose needed post-dialysis.
Hepatic Impairment:
Mild:
Consider lower initial dose and careful titration.
Moderate:
Consider lower initial dose (e.g., 5 mg TID) and careful titration due to extensive hepatic metabolism.
Severe:
Use with extreme caution; significant dose reduction may be necessary. Monitor closely for adverse effects.
Pharmacology
Mechanism of Action
Nifedipine is a dihydropyridine calcium channel blocker that inhibits the transmembrane influx of calcium ions into cardiac muscle and vascular smooth muscle cells. This action leads to coronary and peripheral vasodilation, reducing peripheral vascular resistance and myocardial oxygen demand, thereby lowering blood pressure and improving myocardial blood flow.
Pharmacokinetics
Absorption:
Bioavailability:
45-70% (due to significant first-pass metabolism)
Tmax:
0.5-2 hours (for immediate-release capsules)
FoodEffect:
Food may delay absorption but does not significantly affect the extent of absorption.
Distribution:
Vd:
0.77-1.1 L/kg
ProteinBinding:
92-98%
CnssPenetration:
Limited
Elimination:
HalfLife:
2-5 hours (for immediate-release capsules)
Clearance:
0.5-1.0 L/kg/hr
ExcretionRoute:
Mainly renal (60-80% as inactive metabolites), fecal (15-20%)
Unchanged:
<1%
Pharmacodynamics
OnsetOfAction:
20 minutes (oral)
PeakEffect:
30-60 minutes (oral)
DurationOfAction:
4-8 hours (oral)
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Severe dizziness or fainting
New or worsening chest pain
Abnormal heartbeat
Mood changes
Shortness of breath, significant weight gain, or swelling in the arms or legs
Muscle pain or cramping
Shakiness
Severe constipation or stomach pain, which may indicate a serious bowel problem
Black, tarry, or bloody stools
Vomiting blood or coffee ground-like material
Other Possible Side Effects
Like all medications, this drug can cause side effects. Although many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other symptoms that bother you or persist, contact your doctor:
Dizziness, fatigue, or weakness
Headache
Flushing
Heartburn
Upset stomach
* Feeling nervous or excitable
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects. If you have questions or concerns, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Severe dizziness or fainting
New or worsening chest pain
Abnormal heartbeat
Mood changes
Shortness of breath, significant weight gain, or swelling in the arms or legs
Muscle pain or cramping
Shakiness
Severe constipation or stomach pain, which may indicate a serious bowel problem
Black, tarry, or bloody stools
Vomiting blood or coffee ground-like material
Other Possible Side Effects
Like all medications, this drug can cause side effects. Although many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other symptoms that bother you or persist, contact your doctor:
Dizziness, fatigue, or weakness
Headache
Flushing
Heartburn
Upset stomach
* Feeling nervous or excitable
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects. If you have questions or concerns, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Severe dizziness or fainting
- New or worsening chest pain
- Shortness of breath
- Significant swelling of the hands, ankles, or feet
- Unusual fatigue or weakness
- Irregular heartbeat
Before Using This Medicine
Before taking this medication, it is essential to inform your doctor about the following:
Any allergies you have, including allergies to this drug, its components, or other substances, such as foods or medications. Be sure to describe the symptoms you experienced as a result of the allergy.
If you have recently had a heart attack.
* Any medications you are currently taking, including prescription and over-the-counter (OTC) drugs, natural products, and vitamins. This is crucial because certain medications, such as those used to treat HIV, infections, seizures, and other conditions, should not be taken with this drug. There are numerous medications that interact with this drug, and this list is not exhaustive.
To ensure your safety, it is vital to discuss all of your medications and health conditions with your doctor and pharmacist. They will help you determine whether it is safe to take this medication with your existing medications and health problems. Never start, stop, or change the dose of any medication without first consulting your doctor.
Any allergies you have, including allergies to this drug, its components, or other substances, such as foods or medications. Be sure to describe the symptoms you experienced as a result of the allergy.
If you have recently had a heart attack.
* Any medications you are currently taking, including prescription and over-the-counter (OTC) drugs, natural products, and vitamins. This is crucial because certain medications, such as those used to treat HIV, infections, seizures, and other conditions, should not be taken with this drug. There are numerous medications that interact with this drug, and this list is not exhaustive.
To ensure your safety, it is vital to discuss all of your medications and health conditions with your doctor and pharmacist. They will help you determine whether it is safe to take this medication with your existing medications and health problems. Never start, stop, or change the dose of any medication without first consulting your doctor.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication.
When starting this medication, be cautious when performing tasks that require alertness, such as driving, until you understand how it affects you. To minimize the risk of dizziness or fainting, rise slowly from a sitting or lying down position and exercise caution when navigating stairs.
Although rare, new or worsening chest pain can occur after initiating this medication or increasing the dose, which may lead to a heart attack. This risk is particularly higher in individuals with severe heart blood vessel disease. It is crucial to discuss this with your doctor.
Regularly monitor your blood pressure as instructed by your healthcare provider. Additionally, undergo blood tests as recommended by your doctor and discuss the results with them.
Avoid consuming grapefruit and grapefruit juice while taking this medication. If you have high blood pressure, consult your doctor before using over-the-counter (OTC) products that may increase blood pressure, such as cough or cold medications, diet pills, stimulants, non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or naproxen, and certain natural products or aids.
Be aware that a long-acting form of this medication has been associated with severe stomach and bowel problems, including blockage and ulcers, which may require hospitalization. Discuss these potential risks with your doctor.
Note that this specific form of the medication is not approved for treating high blood pressure. Using it to rapidly lower high blood pressure has led to severe complications, including very low blood pressure, heart attack, and death. However, your doctor may determine that the benefits of taking this medication outweigh the risks. If you are prescribed this medication for high blood pressure, discuss the benefits and risks with your doctor.
If you are 65 years or older, use this medication with caution, as you may be more susceptible to side effects.
Inform your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. It is essential to discuss the potential benefits and risks of this medication to both you and your baby.
When starting this medication, be cautious when performing tasks that require alertness, such as driving, until you understand how it affects you. To minimize the risk of dizziness or fainting, rise slowly from a sitting or lying down position and exercise caution when navigating stairs.
Although rare, new or worsening chest pain can occur after initiating this medication or increasing the dose, which may lead to a heart attack. This risk is particularly higher in individuals with severe heart blood vessel disease. It is crucial to discuss this with your doctor.
Regularly monitor your blood pressure as instructed by your healthcare provider. Additionally, undergo blood tests as recommended by your doctor and discuss the results with them.
Avoid consuming grapefruit and grapefruit juice while taking this medication. If you have high blood pressure, consult your doctor before using over-the-counter (OTC) products that may increase blood pressure, such as cough or cold medications, diet pills, stimulants, non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or naproxen, and certain natural products or aids.
Be aware that a long-acting form of this medication has been associated with severe stomach and bowel problems, including blockage and ulcers, which may require hospitalization. Discuss these potential risks with your doctor.
Note that this specific form of the medication is not approved for treating high blood pressure. Using it to rapidly lower high blood pressure has led to severe complications, including very low blood pressure, heart attack, and death. However, your doctor may determine that the benefits of taking this medication outweigh the risks. If you are prescribed this medication for high blood pressure, discuss the benefits and risks with your doctor.
If you are 65 years or older, use this medication with caution, as you may be more susceptible to side effects.
Inform your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. It is essential to discuss the potential benefits and risks of this medication to both you and your baby.
Overdose Information
Overdose Symptoms:
- Profound hypotension (very low blood pressure)
- Bradycardia (slow heart rate)
- Tachycardia (fast heart rate, reflex)
- Dizziness
- Fainting
- Nausea
- Vomiting
- Lethargy
- Confusion
- Metabolic acidosis
- Hyperglycemia
- Cardiogenic shock
- Pulmonary edema
What to Do:
Seek immediate medical attention. Call 911 or your local emergency number. For poison control, call 1-800-222-1222. Management is supportive and may include IV fluids, vasopressors (e.g., norepinephrine), calcium gluconate, glucagon, and insulin/dextrose.
Drug Interactions
Contraindicated Interactions
- Strong CYP3A4 inducers (e.g., Rifampin, Phenobarbital, Phenytoin, Carbamazepine) - may significantly reduce nifedipine levels and efficacy.
- Grapefruit juice (large quantities) - may significantly increase nifedipine levels and risk of adverse effects.
Major Interactions
- Strong CYP3A4 inhibitors (e.g., Ketoconazole, Itraconazole, Ritonavir, Clarithromycin, Erythromycin) - may increase nifedipine levels and risk of hypotension, edema.
- Beta-blockers (e.g., Metoprolol, Propranolol) - increased risk of severe hypotension or heart failure, especially in patients with impaired ventricular function.
- Quinidine - may decrease quinidine levels or increase nifedipine levels.
- Fentanyl - severe hypotension or increased fluid volume requirements.
- Magnesium sulfate (parenteral) - increased risk of severe hypotension and neuromuscular blockade.
Moderate Interactions
- Moderate CYP3A4 inhibitors (e.g., Diltiazem, Verapamil) - may increase nifedipine levels.
- Alpha-blockers (e.g., Prazosin, Doxazosin) - additive hypotensive effects.
- Digoxin - may increase digoxin levels.
- Cimetidine - may increase nifedipine levels.
- Theophylline - may increase theophylline levels.
- Tacrolimus - may increase tacrolimus levels.
- Cisapride - may increase nifedipine levels.
Minor Interactions
- NSAIDs - may attenuate the hypotensive effect of nifedipine.
- Alcohol - may enhance hypotensive effects.
Monitoring
Baseline Monitoring
Blood Pressure (BP)
Rationale: To establish baseline and guide initial dosing.
Timing: Prior to initiation
Heart Rate (HR)
Rationale: To establish baseline and monitor for reflex tachycardia.
Timing: Prior to initiation
Liver Function Tests (LFTs)
Rationale: Nifedipine is extensively metabolized by the liver; important for patients with pre-existing hepatic impairment.
Timing: Prior to initiation in patients with suspected hepatic impairment
Routine Monitoring
Blood Pressure (BP)
Frequency: Regularly, especially during dose titration and periodically thereafter.
Target: Individualized based on treatment goals (e.g., <130/80 mmHg for hypertension).
Action Threshold: Persistent hypotension (<90/60 mmHg) or uncontrolled hypertension.
Heart Rate (HR)
Frequency: Regularly, especially during dose titration and periodically thereafter.
Target: Typically 60-100 bpm; monitor for reflex tachycardia.
Action Threshold: Persistent tachycardia (>100 bpm) or bradycardia (<50 bpm).
Peripheral Edema
Frequency: Regularly, especially in the lower extremities.
Target: Absence of significant edema.
Action Threshold: Development of new or worsening peripheral edema.
Symptom Monitoring
- Dizziness
- Headache
- Flushing
- Palpitations
- Peripheral edema (swelling of ankles/feet)
- Fatigue
- Nausea
- Gingival hyperplasia (long-term use)
Special Patient Groups
Pregnancy
Nifedipine is Pregnancy Category C. It should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. It has been used off-label for preterm labor and severe preeclampsia, but its use requires careful consideration.
Trimester-Specific Risks:
First Trimester:
Limited data; animal studies show teratogenicity at high doses. Use only if clearly needed.
Second Trimester:
Used for hypertension and preterm labor; generally considered safer than in the first trimester, but still with caution.
Third Trimester:
Used for hypertension and preterm labor; monitor for maternal hypotension and fetal effects.
Lactation
Nifedipine is excreted in breast milk in small amounts. It is generally considered compatible with breastfeeding (L3 - Moderately Safe). Monitor the infant for signs of hypotension or lethargy.
Infant Risk:
Low risk; monitor for drowsiness, poor feeding, or unusual lethargy.
Pediatric Use
Safety and efficacy have not been established for routine pediatric use. Immediate-release nifedipine is generally not recommended for children due to the risk of rapid and unpredictable blood pressure drops. Limited off-label use for hypertensive emergencies under strict medical supervision.
Geriatric Use
Elderly patients may be more sensitive to the hypotensive effects of nifedipine and may have reduced hepatic clearance. Start with lower doses and titrate slowly. Monitor closely for dizziness, falls, and peripheral edema.
Clinical Information
Clinical Pearls
- Immediate-release (IR) nifedipine capsules (like Adalat 20mg) are NOT recommended for acute hypertensive emergencies due to their rapid onset, unpredictable blood pressure lowering, and potential for reflex tachycardia, which can lead to myocardial ischemia or stroke.
- IR nifedipine should be swallowed whole; do not chew, crush, or break the capsules, as this can lead to rapid absorption and an exaggerated hypotensive response.
- Peripheral edema (swelling of ankles/feet) is a common side effect of dihydropyridine calcium channel blockers like nifedipine, due to precapillary vasodilation. It is dose-dependent and often managed by dose reduction or adding an ACE inhibitor/ARB.
- Gingival hyperplasia (gum overgrowth) can occur with long-term use; good oral hygiene is important.
- Patients should be advised to avoid grapefruit and grapefruit juice due to significant CYP3A4 interaction, which can increase nifedipine levels and adverse effects.
- Nifedipine IR is typically dosed multiple times a day (TID or QID) due to its short half-life.
Alternative Therapies
- Other Dihydropyridine Calcium Channel Blockers (e.g., Amlodipine, Felodipine, Nicardipine)
- Non-Dihydropyridine Calcium Channel Blockers (e.g., Verapamil, Diltiazem)
- ACE Inhibitors (e.g., Lisinopril, Enalapril)
- Angiotensin Receptor Blockers (ARBs) (e.g., Valsartan, Losartan)
- Beta-blockers (e.g., Metoprolol, Atenolol)
- Thiazide Diuretics (e.g., Hydrochlorothiazide, Chlorthalidone)
Cost & Coverage
Average Cost:
$10 - $50 per 30 capsules (generic 20mg IR)
Generic Available:
Yes
Insurance Coverage:
Tier 1 or Tier 2 (for generic)
General Drug Facts
If your symptoms or health issues persist or worsen, it's essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so be sure to check with your pharmacist for more information. If you have any questions or concerns about your medication, don't hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek medical attention. When seeking help, be prepared to provide details about the medication taken, the amount, and the time it happened.