Diltiazem
Diltiazem is used to treat high blood pressure, chest pain, and certain heart rhythm disorders. It is available as Cardizem, Tiazac, Cartia XT and is commonly prescribed in the cardiovascular category.
About Diltiazem
Diltiazem is a non-dihydropyridine calcium channel blocker (benzothiazepine) also sold under brand names including Cardizem, Tiazac, and Cartia XT. It is primarily used to diltiazem is prescribed to treat: • High blood pressure, chest pain, and certain heart rhythm disorders • Various related conditions in the cardiovascular category • Associated symptoms and complications It is an important medication that helps manage these conditions effectively. Diltiazem is available in immediate-release tablet (30 mg, 60 mg, 90 mg, 120 mg), extended-release capsule, 12-hour (60 mg, 90 mg, 120 mg), extended-release capsule, 24-hour (120 mg, 180 mg, 240 mg, 300 mg, 360 mg, 420 mg), iv injection (5 mg/ml), and iv powder for reconstitution (25 mg, 50 mg, 100 mg vials) form. Healthcare providers commonly prescribe Diltiazem for conditions including Attention Deficit Hyperactivity Disorder (ADHD), Lupus Anticoagulant, Portal Hypertension, and Secondary Pulmonary Hypertension.
Diltiazem at a Glance
- Brand names
- Cardizem, Tiazac, Cartia XT
- Drug class
- Non-Dihydropyridine Calcium Channel Blocker (Benzothiazepine)
- Pregnancy category
- FDA Category Category C — Animal studies have shown teratogenic effects (skeletal abnormalities, embryo lethality) at doses several times the maximum human dose. There are no adequate well-controlled studies in pregnant women. Use only if the potential benefit justifies the potential risk to the fetus.
- Available forms
- Immediate-release tablet (30 mg, 60 mg, 90 mg, 120 mg), Extended-release capsule, 12-hour (60 mg, 90 mg, 120 mg), Extended-release capsule, 24-hour (120 mg, 180 mg, 240 mg, 300 mg, 360 mg, 420 mg), IV injection (5 mg/mL), IV powder for reconstitution (25 mg, 50 mg, 100 mg vials)
- Therapeutic categories
- Cardiovascular, Calcium Channel Blockers, Hypertension, Arrhythmia
- Conditions treated
- 5 related conditions on this site
What Diltiazem Is Used For
Diltiazem is prescribed to treat:
• High blood pressure, chest pain, and certain heart rhythm disorders • Various related conditions in the cardiovascular category • Associated symptoms and complications
It is an important medication that helps manage these conditions effectively.
Dosage Quick Reference
These are general dosage guidelines for Diltiazem. Your doctor will determine the appropriate dose for your specific situation.
| Condition | Starting Dose | Maintenance Dose |
|---|---|---|
| Hypertension (extended-release) | 180–240 mg once daily | 240–360 mg once daily; max 540 mg/day |
| Chronic stable angina (immediate-release) | 30 mg four times daily | 180–360 mg/day in divided doses |
| Atrial fibrillation — rate control (oral) | 120–180 mg extended-release once daily | Titrate to heart rate goal; max 360 mg/day |
| Atrial fibrillation — rate control (IV bolus) | 0.25 mg/kg IV over 2 minutes | Repeat 0.35 mg/kg if needed; infusion 5–15 mg/hr |
| Paroxysmal supraventricular tachycardia (IV) | 0.25 mg/kg IV over 2 minutes | May repeat 0.35 mg/kg in 15 minutes if needed |
Side Effects
Common side effects may include:
• Nausea or stomach upset • Headache • Dizziness or lightheadedness • Fatigue or tiredness • Mild rash or itching
Serious side effects (seek immediate medical attention):
• Severe allergic reactions (rash, hives, swelling, difficulty breathing) • Unusual bleeding or bruising • Severe stomach pain • Signs of liver problems (yellowing of skin/eyes, dark urine) • Chest pain or irregular heartbeat • Severe dizziness or fainting • Signs of serious adverse effects
See also: Drug Interactions ↓
Drug Interactions
Diltiazem is a moderate inhibitor of CYP3A4 and P-glycoprotein and slows AV nodal conduction, leading to a number of clinically important interactions.
- Beta-blockers (e.g., metoprolol, atenolol, carvedilol): Additive negative inotropy and AV nodal blockade can cause severe bradycardia, heart block, or heart failure. Combine cautiously, particularly in patients with reduced ejection fraction or pre-existing conduction disease.
- Statins metabolized by CYP3A4 (simvastatin, lovastatin): Diltiazem markedly increases statin levels, raising rhabdomyolysis risk. Limit simvastatin to 10 mg/day with diltiazem; consider switching to pravastatin, rosuvastatin, or pitavastatin.
- Digoxin: Diltiazem can raise digoxin levels by 20–50 percent through P-glycoprotein inhibition. Monitor digoxin levels and watch for nausea, visual changes, or arrhythmia.
- Cyclosporine, tacrolimus, sirolimus: Diltiazem significantly increases calcineurin/mTOR inhibitor levels. Monitor trough concentrations closely and adjust immunosuppressant doses.
- CYP3A4 inducers (rifampin, carbamazepine, phenytoin): May reduce diltiazem efficacy. Consider an alternative agent or monitor blood pressure and heart rate response carefully.
- Grapefruit juice: Inhibits intestinal CYP3A4 and can raise diltiazem exposure. Counsel patients to avoid large quantities.
See also: Questions to Ask Your Doctor ↓
Key Considerations
Known drug interactions
Diltiazem has documented interactions with other medications, supplements, and certain foods. Review the Drug Interactions section below and tell your healthcare provider about every medication you take, including over-the-counter products. Jump to section →
Multiple forms available
Diltiazem comes in more than one form (Immediate-release tablet (30 mg, 60 mg, 90 mg, 120 mg), Extended-release capsule, 12-hour (60 mg, 90 mg, 120 mg), Extended-release capsule, 24-hour (120 mg, 180 mg, 240 mg, 300 mg, 360 mg, 420 mg), IV injection (5 mg/mL), IV powder for reconstitution (25 mg, 50 mg, 100 mg vials)). The right form for you depends on your condition, ease of use, and your provider's recommendation.
Additional Information
What is Diltiazem?
Diltiazem (generic name: Diltiazem) is a medication primarily used to treat high blood pressure, chest pain, and certain heart rhythm disorders. It is marketed under the brand name(s) Cardizem, Tiazac, Cartia XT and belongs to the Cardiovascular category of medications.
How Does Diltiazem Work?
Diltiazem works through several mechanisms to provide therapeutic benefits:
- Acts on specific receptors or pathways in the body
- Modulates biological processes related to the treated condition
- Provides symptom relief and improves quality of life
- Helps manage the underlying condition effectively
- Works best when combined with appropriate lifestyle modifications
The medication is designed to target the specific pathways involved in high blood pressure, chest pain, and certain heart rhythm disorders, making it an effective treatment option.
Common Uses
Primary Indications
Diltiazem is commonly prescribed for:
- High blood pressure, chest pain, and certain heart rhythm disorders: The main indication for this medication
- Related Conditions: Associated symptoms and complications
- Prevention: May help prevent progression of certain conditions
- Symptom Management: Reduces discomfort and improves daily function
Additional Uses
In some cases, Diltiazem may also be prescribed for:
- Off-label uses as determined by your healthcare provider
- Combination therapy with other medications
- Long-term management of chronic conditions
- Short-term treatment of acute symptoms
Dosage and Administration
Diltiazem dosing varies based on the specific condition being treated and individual patient factors.
Typical Dosing:
- Starting dose is typically determined by your healthcare provider
- May be adjusted based on response and tolerability
- Can be taken with or without food (follow specific instructions)
- Usually taken once or twice daily
Administration Tips:
- Take at the same time(s) each day for best results
- Swallow tablets/capsules whole unless instructed otherwise
- Don't skip doses
- Complete full course of treatment as prescribed
- Follow your doctor's specific instructions carefully
Important Safety Information
Who Should Not Take Diltiazem?
Do not take Diltiazem if you:
- Are allergic to Diltiazem or any ingredients
- Have certain medical conditions (discuss with your doctor)
- Are taking medications that interact with Diltiazem
- Have severe liver or kidney disease (without dose adjustment)
Drug Interactions
Inform your doctor about all medications you take, including:
- Prescription medications
- Over-the-counter drugs
- Vitamins and supplements
- Herbal products
Some medications may interact with Diltiazem, affecting its efficacy or increasing side effect risk.
Pregnancy and Breastfeeding
Pregnancy:
- Discuss risks and benefits with your doctor if pregnant or planning pregnancy
- May require special monitoring or dose adjustments
- Some medications should be avoided during pregnancy
Breastfeeding:
- Consult your doctor about safety while breastfeeding
- May pass into breast milk
- Benefits and risks should be carefully considered
Monitoring and Follow-Up
While taking Diltiazem, your doctor may monitor:
- Effectiveness of treatment (symptom improvement)
- Side effects or adverse reactions
- Laboratory values if applicable
- Blood pressure, heart rate, or other vital signs as appropriate
- Overall response to therapy
Regular follow-up appointments are important to ensure the medication is working properly and to make any necessary adjustments.
Managing Side Effects
Most side effects are mild and improve with time. Here are strategies for common side effects:
Gastrointestinal Upset
- Take with food if allowed
- Stay well hydrated
- Eat smaller, more frequent meals
- Report persistent nausea or vomiting
Dizziness
- Rise slowly from sitting or lying positions
- Avoid sudden movements
- Stay hydrated
- Avoid alcohol
- Report severe or persistent dizziness
Fatigue
- Get adequate rest
- Maintain regular sleep schedule
- Exercise as tolerated
- Report excessive tiredness that interferes with daily activities
Lifestyle Considerations
To maximize the benefits of Diltiazem:
- Follow a healthy, balanced diet
- Exercise regularly as recommended by your doctor
- Maintain a healthy weight
- Avoid alcohol or limit consumption
- Don't smoke
- Manage stress through relaxation techniques
- Get adequate sleep
- Stay well hydrated
- Keep all follow-up appointments
- Take medication consistently as prescribed
When to Contact Your Doctor
Seek immediate medical attention if you experience:
- Signs of severe allergic reaction (difficulty breathing, severe rash, swelling)
- Chest pain or rapid heartbeat
- Severe dizziness or fainting
- Unusual bleeding or bruising
- Signs of liver problems (yellowing of skin/eyes, dark urine, severe fatigue)
- Severe stomach pain
- Any symptoms that concern you
Contact your doctor for non-emergency issues:
- Mild to moderate side effects that persist
- Questions about your medication
- Concerns about effectiveness
- New medications prescribed by another doctor
- Scheduled surgery or dental procedures
- Planning pregnancy
Storage
Store Diltiazem at room temperature (68-77°F or 20-25°C) away from light, heat, and moisture. Keep in original container. Keep out of reach of children and pets. Do not use past expiration date.
Important Reminders
- Take exactly as prescribed by your doctor
- Don't stop suddenly without medical advice
- Keep all follow-up appointments
- Report any unusual symptoms
- Don't share medication with others
- Store safely away from children
- Check expiration dates
- Ask your pharmacist if you have questions
Clinical Benefits
When used appropriately, Diltiazem provides several benefits:
- Effective management of high blood pressure, chest pain, and certain heart rhythm disorders
- Improvement in quality of life
- Reduction in symptoms
- Prevention of complications
- Generally well-tolerated when used as directed
- Backed by clinical research and extensive use
Disclaimer: This information is for educational purposes only and is not intended to replace professional medical advice, diagnosis, or treatment. Always consult your physician or other qualified healthcare provider with any questions about a medical condition or medication.
Frequently Asked Questions
Questions to Ask Your Doctor About Diltiazem
Consider discussing these topics at your next appointment:
- Is diltiazem the best calcium channel blocker for my specific condition, or would amlodipine be more appropriate?
- How often should I check my blood pressure and pulse at home, and what readings should prompt me to call you?
- Are any of my current medications, especially statins or beta-blockers, going to interact with diltiazem?
- What symptoms of side effects should I watch for, and which ones are urgent?
- How will we know if diltiazem is controlling my condition well enough?
Medical Disclaimer: This information is for educational purposes only and should not be considered medical advice. Always consult with your healthcare provider before starting, stopping, or changing any medication. Your doctor can provide personalized recommendations based on your specific health condition and medical history.