Cartia (diltiazem) 300mgxt Caps
It is used to treat high blood pressure.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, Antiarrhythmic
Pharmacologic Class
Calcium Channel Blocker (Non-dihydropyridine)
Pregnancy Category
Category C
FDA Approved
Jan 1970
DEA Schedule
Not Controlled
Overview
What is this medicine?
Diltiazem is a medication that helps relax blood vessels and slow down your heart rate. This can lower your blood pressure, reduce chest pain (angina), and help control an irregular heartbeat like atrial fibrillation.
How to Use This Medicine
Taking Your Medication Correctly
To get the most benefit from your medication, follow these guidelines:
Take your medication exactly as directed by your doctor.
Read all the information provided with your medication and follow the instructions carefully.
Take your medication at the same time every day to establish a routine.
Continue taking your medication as prescribed by your doctor or healthcare provider, even if you start to feel better.
Some medications may need to be taken with food or on an empty stomach, while others may not have specific requirements. Check with your pharmacist to determine the best way to take your medication.
Special Instructions for Certain Medications
Some products can be opened and mixed with a spoonful of applesauce, while others must be swallowed whole. Check with your pharmacist to see if your medication can be opened or mixed with food.
Storing and Disposing of Your Medication
To keep your medication effective and safe:
Store your medication at room temperature, protected from light and moisture.
Keep your medication in a dry place, away from the bathroom.
Store all medications in a safe and secure location, out of the reach of children and pets.
Dispose of unused or expired medications properly. Do not flush them down the toilet or pour them down the drain unless instructed to do so by your pharmacist.
Check with your pharmacist for guidance on disposing of medications, and consider participating in a local drug take-back program.
What to Do If You Miss a Dose
If you miss a dose of your medication:
Take the missed dose as soon as you remember.
If it's close to the time for your next dose, skip the missed dose and resume your regular schedule.
Do not take two doses at the same time or take extra doses to make up for a missed dose.
To get the most benefit from your medication, follow these guidelines:
Take your medication exactly as directed by your doctor.
Read all the information provided with your medication and follow the instructions carefully.
Take your medication at the same time every day to establish a routine.
Continue taking your medication as prescribed by your doctor or healthcare provider, even if you start to feel better.
Some medications may need to be taken with food or on an empty stomach, while others may not have specific requirements. Check with your pharmacist to determine the best way to take your medication.
Special Instructions for Certain Medications
Some products can be opened and mixed with a spoonful of applesauce, while others must be swallowed whole. Check with your pharmacist to see if your medication can be opened or mixed with food.
Storing and Disposing of Your Medication
To keep your medication effective and safe:
Store your medication at room temperature, protected from light and moisture.
Keep your medication in a dry place, away from the bathroom.
Store all medications in a safe and secure location, out of the reach of children and pets.
Dispose of unused or expired medications properly. Do not flush them down the toilet or pour them down the drain unless instructed to do so by your pharmacist.
Check with your pharmacist for guidance on disposing of medications, and consider participating in a local drug take-back program.
What to Do If You Miss a Dose
If you miss a dose of your medication:
Take the missed dose as soon as you remember.
If it's close to the time for your next dose, skip the missed dose and resume your regular schedule.
Do not take two doses at the same time or take extra doses to make up for a missed dose.
Lifestyle & Tips
- Take your medication exactly as prescribed, usually once daily. Do not crush, chew, or divide the extended-release capsules.
- Maintain a healthy diet, low in sodium and saturated fats.
- Engage in regular physical activity as advised by your doctor.
- Limit alcohol consumption.
- Avoid smoking.
- Monitor your blood pressure and heart rate at home if advised by your doctor.
- Report any new or worsening symptoms to your healthcare provider.
Available Forms & Alternatives
Dosing & Administration
Adult Dosing
Standard Dose:
300 mg orally once daily (for Cartia XT)
Dose Range:
120 - 480 mg
Condition-Specific Dosing:
hypertension:
Initial: 180-240 mg once daily; Maintenance: 240-480 mg once daily. Cartia XT 300mg is a common maintenance dose.
chronicstableangina:
Initial: 120-240 mg once daily; Maintenance: 240-480 mg once daily. Cartia XT 300mg is a common maintenance dose.
atrialfibrillation_flutter_ratecontrol:
Dosing for rate control with extended-release formulations may vary, often starting lower and titrating based on heart rate response. 300mg once daily can be used for maintenance.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established (safety and efficacy not established for extended-release formulations)
Adolescent:
Not established (safety and efficacy not established for extended-release formulations)
Dose Adjustments
Renal Impairment:
Mild:
No specific dose adjustment generally required, but monitor closely.
Moderate:
Use with caution; consider lower initial doses and careful titration.
Severe:
Use with caution; consider lower initial doses and careful titration due to potential for accumulation of metabolites.
Dialysis:
Diltiazem is not significantly removed by hemodialysis. Use with caution, monitor for exaggerated effects.
Hepatic Impairment:
Mild:
Use with caution; monitor for exaggerated effects.
Moderate:
Use with caution; consider lower initial doses and careful titration due to extensive hepatic metabolism.
Severe:
Contraindicated or use with extreme caution; significant dose reduction is likely necessary. Monitor closely for adverse effects.
Pharmacology
Mechanism of Action
Diltiazem is a non-dihydropyridine calcium channel blocker that inhibits the influx of extracellular calcium ions across the membranes of myocardial and vascular smooth muscle cells. This leads to a reduction in myocardial contractility, slowing of AV nodal conduction, and relaxation of vascular smooth muscle, resulting in peripheral and coronary vasodilation. These actions decrease myocardial oxygen demand and increase myocardial oxygen supply.
Pharmacokinetics
Absorption:
Bioavailability:
Approximately 35-65% (due to extensive first-pass metabolism)
Tmax:
6-11 hours (for extended-release formulations)
FoodEffect:
Food may increase the rate and extent of absorption for some extended-release formulations, but generally can be taken with or without food. Consult specific product labeling.
Distribution:
Vd:
Approximately 5.3 L/kg
ProteinBinding:
70-85%
CnssPenetration:
Limited
Elimination:
HalfLife:
5-10 hours (for extended-release formulations)
Clearance:
Not available (highly variable due to first-pass effect)
ExcretionRoute:
Primarily urine (60-65%) and feces (35%)
Unchanged:
<5% (in urine)
Pharmacodynamics
OnsetOfAction:
Within 30 minutes to 2 hours (for extended-release formulations, clinical effect may take longer to stabilize)
PeakEffect:
6-11 hours (for extended-release formulations)
DurationOfAction:
24 hours (for once-daily extended-release formulations)
Confidence:
High
Safety & Warnings
Side Effects
Urgent 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 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
Signs of liver problems, including:
+ Dark urine
+ Tiredness
+ Decreased appetite
+ Upset stomach or stomach pain
+ Light-colored stools
+ Vomiting
+ Yellow skin or eyes
Severe dizziness or fainting
Slow heartbeat
New or worsening abnormal heartbeat
Worsening heart failure (if you have a history of heart failure), characterized by:
+ Shortness of breath
+ Significant weight gain
+ Swelling in the arms or legs
Severe skin reactions, including:
+ Stevens-Johnson syndrome (SJS)
+ Toxic epidermal necrolysis (TEN)
+ Other severe skin reactions, which may be life-threatening
+ Symptoms may include:
- Red, swollen, blistered, or peeling skin
- Skin irritation (with or without fever)
- Red or irritated eyes
- Sores in the mouth, throat, nose, or eyes
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 or any other symptoms that bother you or do not go away, contact your doctor:
Headache
* Feeling dizzy, tired, or weak
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects. If you have questions or concerns about side effects, 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.
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 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
Signs of liver problems, including:
+ Dark urine
+ Tiredness
+ Decreased appetite
+ Upset stomach or stomach pain
+ Light-colored stools
+ Vomiting
+ Yellow skin or eyes
Severe dizziness or fainting
Slow heartbeat
New or worsening abnormal heartbeat
Worsening heart failure (if you have a history of heart failure), characterized by:
+ Shortness of breath
+ Significant weight gain
+ Swelling in the arms or legs
Severe skin reactions, including:
+ Stevens-Johnson syndrome (SJS)
+ Toxic epidermal necrolysis (TEN)
+ Other severe skin reactions, which may be life-threatening
+ Symptoms may include:
- Red, swollen, blistered, or peeling skin
- Skin irritation (with or without fever)
- Red or irritated eyes
- Sores in the mouth, throat, nose, or eyes
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 or any other symptoms that bother you or do not go away, contact your doctor:
Headache
* Feeling dizzy, tired, or weak
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects. If you have questions or concerns about side effects, 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 lightheadedness, especially when standing up.
- Fainting spells.
- Very slow heart rate (e.g., less than 50 beats per minute).
- New or worsening swelling in your ankles, feet, or legs.
- Shortness of breath, especially with exertion or lying down.
- Unusual fatigue or weakness.
- Persistent headache.
- Signs of liver problems (e.g., yellowing of skin/eyes, dark urine, severe stomach pain).
Before Using This Medicine
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.
Certain types of abnormal heart rhythms, as this medication is not suitable for individuals with specific heart rhythm disorders. If you are unsure, consult your doctor or pharmacist for guidance.
Existing health conditions, including:
+ Fluid accumulation in the lungs
+ Low blood pressure
+ Recent heart attack
Current medications, particularly:
+ Ivabradine
+ Rifampin
Please note that this is not an exhaustive list of all potential interactions. It is crucial to discuss all your medications (prescription, over-the-counter, natural products, and vitamins) and health problems with your doctor and pharmacist to ensure safe use. Never start, stop, or adjust the dosage of any medication without first consulting your doctor to confirm it is safe to do so.
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.
Certain types of abnormal heart rhythms, as this medication is not suitable for individuals with specific heart rhythm disorders. If you are unsure, consult your doctor or pharmacist for guidance.
Existing health conditions, including:
+ Fluid accumulation in the lungs
+ Low blood pressure
+ Recent heart attack
Current medications, particularly:
+ Ivabradine
+ Rifampin
Please note that this is not an exhaustive list of all potential interactions. It is crucial to discuss all your medications (prescription, over-the-counter, natural products, and vitamins) and health problems with your doctor and pharmacist to ensure safe use. Never start, stop, or adjust the dosage of any medication without first consulting your doctor to confirm it is safe to do so.
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, get up slowly from a sitting or lying position, and be careful when climbing stairs.
Follow your doctor's instructions for monitoring your blood pressure and heart rate. You may need to undergo an electrocardiogram (ECG) before initiating treatment and periodically while taking this medication. Discuss any concerns or questions with your doctor.
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.
If you regularly consume grapefruit juice or eat grapefruit, discuss this with your doctor, as it may interact with your medication. Additionally, you may need to avoid consuming alcohol while taking this medication; consult your doctor or pharmacist for guidance.
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, as they will need to discuss the potential benefits and risks of this medication to 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, get up slowly from a sitting or lying position, and be careful when climbing stairs.
Follow your doctor's instructions for monitoring your blood pressure and heart rate. You may need to undergo an electrocardiogram (ECG) before initiating treatment and periodically while taking this medication. Discuss any concerns or questions with your doctor.
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.
If you regularly consume grapefruit juice or eat grapefruit, discuss this with your doctor, as it may interact with your medication. Additionally, you may need to avoid consuming alcohol while taking this medication; consult your doctor or pharmacist for guidance.
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, as they will need to discuss the potential benefits and risks of this medication to you and your baby.
Overdose Information
Overdose Symptoms:
- Severe hypotension (very low blood pressure)
- Profound bradycardia (very slow heart rate)
- High-degree AV block (heart block)
- Asystole (cardiac arrest)
- Cardiogenic shock
- Confusion
- Drowsiness
What to Do:
Seek immediate medical attention. Call 911 or your local emergency number. For advice, call a poison control center at 1-800-222-1222. Treatment is supportive and may include IV fluids, atropine, glucagon, calcium gluconate, vasopressors, and cardiac pacing.
Drug Interactions
Contraindicated Interactions
- Ivabradine (increased risk of bradycardia)
- Dantrolene (IV, risk of hyperkalemia and myocardial depression)
Major Interactions
- Beta-blockers (additive negative chronotropic and inotropic effects, increased risk of bradycardia, AV block, heart failure)
- Digoxin (increased digoxin serum concentrations)
- Amiodarone (increased risk of bradycardia, sinus arrest, AV block)
- Statins (e.g., Simvastatin, Lovastatin - increased statin levels due to CYP3A4 inhibition, leading to increased risk of myopathy/rhabdomyolysis)
- Immunosuppressants (e.g., Cyclosporine, Tacrolimus, Sirolimus - increased immunosuppressant levels due to CYP3A4 inhibition)
- Midazolam, Triazolam (increased benzodiazepine levels due to CYP3A4 inhibition)
- Alpha-blockers (e.g., Prazosin, Doxazosin - additive hypotensive effects)
- Fingolimod (increased risk of bradycardia)
Moderate Interactions
- Other antihypertensives (additive hypotensive effects)
- Grapefruit juice (may increase diltiazem levels due to CYP3A4 inhibition)
- Carbamazepine (increased carbamazepine levels)
- Phenytoin (increased phenytoin levels)
- Rifampin (decreased diltiazem levels)
- Cimetidine (increased diltiazem levels)
Minor Interactions
- NSAIDs (may reduce antihypertensive effect)
Monitoring
Baseline Monitoring
Blood Pressure (BP)
Rationale: To establish baseline and guide initial dosing for hypertension/angina.
Timing: Prior to initiation of therapy.
Heart Rate (HR)
Rationale: To establish baseline and assess for bradycardia, especially important for rate control in AFib/flutter.
Timing: Prior to initiation of therapy.
Electrocardiogram (ECG)
Rationale: To assess baseline cardiac rhythm, PR interval, and rule out pre-existing conduction abnormalities.
Timing: Prior to initiation of therapy.
Liver Function Tests (LFTs)
Rationale: Diltiazem is extensively metabolized by the liver; to assess baseline hepatic function.
Timing: Prior to initiation of therapy, especially in patients with suspected hepatic impairment.
Renal Function (BUN, Creatinine)
Rationale: To assess baseline renal function, though renal excretion of unchanged drug is minimal.
Timing: Prior to initiation of therapy.
Routine Monitoring
Blood Pressure (BP)
Frequency: Regularly, especially during dose titration and periodically thereafter (e.g., weekly during titration, then monthly/quarterly)
Target: <130/80 mmHg (or individualized target)
Action Threshold: Persistent readings above target or symptomatic hypotension.
Heart Rate (HR)
Frequency: Regularly, especially during dose titration and periodically thereafter (e.g., weekly during titration, then monthly/quarterly)
Target: 50-90 bpm (or individualized target for rate control)
Action Threshold: Persistent bradycardia (<50 bpm) or symptomatic bradycardia.
Electrocardiogram (ECG) - PR interval
Frequency: Periodically, especially with dose increases or concomitant use of other AV nodal blocking agents.
Target: <0.20 seconds (or no significant prolongation from baseline)
Action Threshold: Significant PR prolongation (>0.24 seconds) or development of higher-degree AV block.
Signs/Symptoms of Peripheral Edema
Frequency: At each visit
Target: Absence of significant edema
Action Threshold: Development of new or worsening peripheral edema.
Symptom Monitoring
- Dizziness
- Lightheadedness
- Fainting (syncope)
- Slow heart rate (bradycardia)
- Shortness of breath
- Swelling in ankles, feet, or legs (peripheral edema)
- Chest pain (angina, if not controlled)
- Fatigue
- Headache
- Gingival hyperplasia (gum overgrowth)
Special Patient Groups
Pregnancy
Diltiazem is Pregnancy Category C. It should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Animal studies have shown adverse effects, but there are no adequate and well-controlled studies in pregnant women.
Trimester-Specific Risks:
First Trimester:
Potential for fetal harm based on animal data; use only if clearly needed.
Second Trimester:
Use with caution; monitor fetal growth and well-being.
Third Trimester:
Use with caution; monitor for potential effects on fetal heart rate and uterine contractility.
Lactation
Diltiazem is excreted in breast milk. The American Academy of Pediatrics considers it compatible with breastfeeding, but caution is advised. Monitor the infant for signs of bradycardia, hypotension, or sedation.
Infant Risk:
L3 (Moderately safe; monitor infant for adverse effects).
Pediatric Use
Safety and efficacy of extended-release diltiazem formulations have not been established in pediatric patients. Use is generally not recommended.
Geriatric Use
Elderly patients may be more sensitive to the effects of diltiazem, particularly regarding bradycardia and hypotension. Start with lower doses and titrate slowly, monitoring closely for adverse effects.
Clinical Information
Clinical Pearls
- Extended-release diltiazem capsules (like Cartia XT) must be swallowed whole; do not crush, chew, or divide them, as this can lead to rapid release of the drug and potential overdose.
- Some extended-release capsules may be opened and the contents sprinkled on soft food (e.g., applesauce) for patients who have difficulty swallowing, but verify this for the specific product (Cartia XT can be opened and sprinkled).
- Diltiazem can cause gingival hyperplasia (gum overgrowth) with long-term use; good oral hygiene is important.
- It is a common choice for rate control in atrial fibrillation or flutter, especially in patients with concomitant hypertension or angina.
- Patients should be advised to avoid grapefruit juice due to potential for increased diltiazem levels.
Alternative Therapies
- For hypertension: ACE inhibitors, Angiotensin Receptor Blockers (ARBs), Thiazide diuretics, Beta-blockers, Dihydropyridine calcium channel blockers (e.g., amlodipine, nifedipine).
- For angina: Beta-blockers, Nitrates, Ranolazine.
- For rate control in atrial fibrillation/flutter: Beta-blockers, Digoxin.
Cost & Coverage
Average Cost:
Varies widely, typically $50 - $300+ per 30 capsules (Cartia XT 300mg)
Generic Available:
Yes
Insurance Coverage:
Generic diltiazem is typically Tier 1 or 2. Brand-name Cartia XT may be Tier 3 or higher, requiring prior authorization.
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.