Nifedipine 30mg ER (cc) Tablets

Nifedipine is a dihydropyridine calcium channel blocker. It inhibits the transmembrane influx of calcium ions into cardiac muscle and smooth muscle cells. This inhibition leads to relaxation of vascular smooth muscle, resulting in peripheral arterial vasodilation and reduction in peripheral vascular resistance. This reduces afterload, leading to a decrease in systemic blood pressure. In angina, it reduces myocardial oxygen demand by decreasing afterload and may increase myocardial oxygen supply by dilating coronary arteries.

Serious Side Effects: Seek Medical Help Right Away

Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor immediately or seek emergency 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 be signs of 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. While 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, contact your doctor if they bother you or do not go away:

Dizziness, tiredness, or weakness
Headache
Flushing
Heartburn
Upset stomach
* Feeling nervous and excitable

Note: For some brands, you may notice the tablet shell in your stool. This is normal and not a cause for concern. If you have questions, consult your doctor.

Reporting Side Effects

This list is not exhaustive, and you may experience other side effects. If you have questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.

Before Taking This Medication: Important Information to Share with Your Doctor

It is essential to inform your doctor about the following:

Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
If you have been diagnosed with intolerance to certain sugars, including lactose, glucose, or galactose. Some formulations of this medication may contain lactose.
If you have recently experienced a heart attack.
If you are taking any medications, including prescription and over-the-counter (OTC) drugs, natural products, or vitamins, that may interact with this medication. Specifically, certain medications used to treat HIV, infections, seizures, and other conditions should not be taken with this drug. However, this is not an exhaustive list of all potential interactions.

To ensure your safety, it is crucial to provide your doctor and pharmacist with a comprehensive list of all your medications, including prescription and OTC drugs, natural products, and vitamins, as well as any health problems you are experiencing. This will enable them to verify that it is safe for you to take this medication in conjunction with your other medications and health conditions. Never start, stop, or adjust the dosage of any medication without first consulting your doctor.

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, stand up slowly after sitting or lying down, and exercise caution when climbing stairs.

Although rare, new or worsening chest pain can occur after initiating this medication or increasing the dose, which may increase the risk of 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 directed by your healthcare provider. Additionally, have your blood tested 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 this risk with your doctor.

If you are 65 years or older, use this medication with caution, as you may be more susceptible to side effects.

If you are pregnant, planning to become pregnant, or breastfeeding, inform your doctor to discuss the potential benefits and risks to you and your baby.

• Rifampin (strong CYP3A4 inducer, significantly reduces nifedipine levels)
• St. John's Wort (strong CYP3A4 inducer, significantly reduces nifedipine levels)

• Strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, clarithromycin, ritonavir, nefazodone): May significantly increase nifedipine levels, leading to increased hypotensive effects and adverse reactions.
• Grapefruit juice: Inhibits CYP3A4, significantly increases nifedipine levels. Avoid concurrent use.
• Quinidine: May decrease quinidine levels or increase nifedipine levels.
• Cimetidine: May increase nifedipine levels.
• Phenytoin, Carbamazepine, Phenobarbital: May decrease nifedipine levels (CYP3A4 induction).

• Beta-blockers: May cause additive hypotensive effects or exacerbate heart failure in susceptible patients. Monitor blood pressure and heart rate.
• Digoxin: May increase digoxin levels. Monitor digoxin levels.
• Theophylline: May increase theophylline levels.
• Fentanyl: Severe hypotension has been reported with concomitant use of beta-blockers and calcium channel blockers.
• Magnesium sulfate: Increased risk of hypotension and neuromuscular blockade.
• Tacrolimus: May increase tacrolimus levels. Monitor tacrolimus levels and adjust dose.
• Cisapride: May increase nifedipine levels.

• NSAIDs: May attenuate the antihypertensive effect of nifedipine.
• Alpha-blockers (e.g., prazosin): May cause additive hypotensive effects, especially orthostatic hypotension.

• Headache
• Dizziness/Lightheadedness
• Flushing
• Palpitations
• Peripheral edema (swelling of ankles/feet)
• Fatigue
• Nausea
• Chest pain (if worsening or new onset)

Nifedipine is Pregnancy Category C. Studies in animals have shown adverse effects on the fetus. There are no adequate and well-controlled studies in pregnant women. It should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. It is sometimes used off-label for preterm labor or severe preeclampsia/eclampsia.

Nifedipine is excreted in breast milk in small amounts. The American Academy of Pediatrics considers it compatible with breastfeeding. Monitor the infant for signs of hypotension (e.g., lethargy, poor feeding) or bradycardia, though these are unlikely with typical maternal doses.

Safety and efficacy have not been established for routine use in pediatric patients for hypertension or angina. Immediate-release nifedipine has been used off-label in pediatric hypertensive emergencies or pulmonary hypertension, but extended-release formulations are generally not recommended due to lack of data and difficulty with dose titration.

Use with caution in elderly patients, as they may be more sensitive to the hypotensive effects and may have reduced hepatic clearance. Start with lower doses and titrate slowly. Monitor blood pressure closely to avoid excessive hypotension.

• Nifedipine ER tablets must be swallowed whole; do not chew, crush, or divide, as this can lead to rapid release of the drug and potentially severe hypotension.
• The tablet shell may be excreted in the stool; this is normal and does not mean the medication was not absorbed.
• Peripheral edema is a common side effect, especially at higher doses. It is dose-dependent and due to arterial vasodilation, not fluid retention. It may be managed by dose reduction, adding a diuretic, or switching to another class of antihypertensive.
• Avoid abrupt discontinuation, especially in patients with angina, as it may precipitate angina or myocardial infarction.
• Grapefruit juice significantly increases nifedipine levels due to CYP3A4 inhibition; advise patients to avoid it.
• Nifedipine ER is generally preferred over immediate-release nifedipine for chronic hypertension due to smoother blood pressure control and reduced risk of reflex tachycardia.

• Other Dihydropyridine Calcium Channel Blockers (e.g., Amlodipine, Felodipine, Nicardipine)
• Non-Dihydropyridine Calcium Channel Blockers (e.g., Verapamil, Diltiazem - different mechanism, affects heart rate/conduction more)
• ACE Inhibitors (e.g., Lisinopril, Enalapril)
• Angiotensin Receptor Blockers (ARBs) (e.g., Valsartan, Losartan)
• Thiazide Diuretics (e.g., Hydrochlorothiazide, Chlorthalidone)
• Beta-blockers (e.g., Metoprolol, Atenolol)
• Other Antihypertensives (e.g., Alpha-blockers, direct vasodilators)

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.