Dilacor XR 120mg Capsules
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
Pharmacologic Class
Calcium Channel Blocker (Non-dihydropyridine)
Pregnancy Category
Category C
FDA Approved
Sep 1992
DEA Schedule
Not Controlled
Overview
What is this medicine?
Diltiazem is a medication called a calcium channel blocker. It works by relaxing blood vessels, which helps lower blood pressure and improve blood flow to the heart, reducing chest pain (angina). It also helps slow down your heart rate.
How to Use This Medicine
Taking Your Medication Correctly
To get the most benefit from your medication, it's essential to take it as directed by your doctor. Carefully read all the information provided with your prescription, and follow the instructions closely. 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 feeling better.
Some medications may need to be taken with food, while others should be taken on an empty stomach. Check with your pharmacist to determine the best way to take your specific medication. Additionally, some products can be opened and mixed with a spoonful of applesauce, while others must be swallowed whole. Consult with your pharmacist to see if your medication can be opened.
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. Dispose of any 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. If you have questions about disposing of your medication, consult with your pharmacist, who can also inform you about potential drug take-back programs in your area.
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 as directed by your doctor. Carefully read all the information provided with your prescription, and follow the instructions closely. 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 feeling better.
Some medications may need to be taken with food, while others should be taken on an empty stomach. Check with your pharmacist to determine the best way to take your specific medication. Additionally, some products can be opened and mixed with a spoonful of applesauce, while others must be swallowed whole. Consult with your pharmacist to see if your medication can be opened.
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. Dispose of any 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. If you have questions about disposing of your medication, consult with your pharmacist, who can also inform you about potential drug take-back programs in your area.
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 the medication exactly as prescribed, usually once daily. Do not crush, chew, or break the extended-release capsule; swallow it whole.
- Take it at the same time each day to maintain consistent levels in your body.
- Do not stop taking this medication suddenly without consulting your doctor, as it can worsen your condition.
- Monitor your blood pressure and heart rate regularly at home if advised by your doctor.
- Avoid grapefruit and grapefruit juice while taking this medication, as it can increase the drug's effects and side effects.
- Limit alcohol consumption, as it can increase the blood pressure-lowering effects.
- Maintain a healthy lifestyle, including a balanced diet (low in sodium and saturated fats), regular exercise, and stress management, to support blood pressure control.
- Inform your doctor or dentist that you are taking diltiazem before any surgery or dental procedures.
Available Forms & Alternatives
Available Strengths:
Generic Alternatives:
Dosing & Administration
Adult Dosing
Standard Dose:
120 mg once daily
Dose Range:
120 - 480 mg
Condition-Specific Dosing:
hypertension:
Initial 180-240 mg once daily; titrate up to 480 mg once daily based on response.
chronicStableAngina:
Initial 120-180 mg once daily; titrate up to 480 mg once daily based on response.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established
Adolescent:
Not established
Dose Adjustments
Renal Impairment:
Mild:
No specific adjustment recommended, monitor response.
Moderate:
No specific adjustment recommended, monitor response.
Severe:
Use with caution, monitor for exaggerated effects. Dose reduction may be necessary.
Dialysis:
Diltiazem is not significantly removed by hemodialysis. Administer after dialysis if needed, monitor closely.
Hepatic Impairment:
Mild:
Use with caution, monitor for exaggerated effects.
Moderate:
Start with lower doses (e.g., 60-90 mg once daily) and titrate slowly. Monitor for exaggerated effects.
Severe:
Contraindicated or use with extreme caution and significant dose reduction. Monitor closely for adverse effects.
Confidence:
Medium
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 relaxation of vascular smooth muscle, resulting in peripheral vasodilation and reduced systemic vascular resistance, thereby lowering blood pressure. In the heart, it decreases myocardial contractility, slows sinoatrial (SA) and atrioventricular (AV) nodal conduction, and prolongs AV nodal refractoriness, which reduces heart rate and can be beneficial in angina by decreasing myocardial oxygen demand.
Pharmacokinetics
Absorption:
Bioavailability:
40-65% (due to extensive first-pass metabolism)
Tmax:
10-14 hours (for extended-release formulations)
FoodEffect:
Food may increase bioavailability and delay Tmax, but overall effect on AUC is minimal for some ER formulations. Should be taken consistently with or without food.
Distribution:
Vd:
5.3 L/kg
ProteinBinding:
70-80%
CnssPenetration:
Limited
Elimination:
HalfLife:
5-8 hours (parent drug, but effective half-life for ER formulations is longer due to sustained release)
Clearance:
Not available (highly variable due to first-pass metabolism)
ExcretionRoute:
Renal (35-65%), Fecal (35-65%)
Unchanged:
<5% (in urine)
Pharmacodynamics
OnsetOfAction:
Within hours (for extended-release formulations)
PeakEffect:
10-14 hours
DurationOfAction:
24 hours
Safety & Warnings
Side Effects
Important Side Effects to Report to Your Doctor Immediately
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, seek medical attention right away:
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
+ Signs of severe skin reactions include:
- Red, swollen, blistered, or peeling skin
- Other skin irritation (with or without fever)
- Red or irritated eyes
- Sores in the mouth, throat, nose, or eyes
Other Possible Side Effects
Most people do not experience significant side effects, but some may occur. If you notice any of the following side effects or any other unusual symptoms, contact your doctor for advice:
Headache
* Feeling dizzy, tired, or weak
This is not an exhaustive list of possible side effects. If you have concerns or questions, 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, seek medical attention right away:
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
+ Signs of severe skin reactions include:
- Red, swollen, blistered, or peeling skin
- Other skin irritation (with or without fever)
- Red or irritated eyes
- Sores in the mouth, throat, nose, or eyes
Other Possible Side Effects
Most people do not experience significant side effects, but some may occur. If you notice any of the following side effects or any other unusual symptoms, contact your doctor for advice:
Headache
* Feeling dizzy, tired, or weak
This is not an exhaustive list of possible side effects. If you have concerns or questions, 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
- Very slow heart rate (less than 50 beats per minute)
- New or worsening swelling in your hands, ankles, or feet
- Shortness of breath, especially with exertion or lying down
- Chest pain that is new or worsening
- Signs of liver problems (e.g., yellowing of skin/eyes, dark urine, persistent nausea/vomiting, severe stomach pain)
- Severe skin rash or allergic reaction (e.g., hives, difficulty breathing, swelling of face/lips/tongue/throat)
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. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
Certain types of abnormal heart rhythms, as this medication is not suitable for use with many types of irregular heartbeats. If you are unsure, consult your doctor or pharmacist for guidance.
Specific health conditions, including:
+ Fluid accumulation in the lungs
+ Low blood pressure
+ Recent heart attack
Concurrent use of certain medications, such as:
+ Ivabradine
+ Rifampin
This list is not exhaustive, and it is crucial to disclose all your medications (prescription, over-the-counter, natural products, and vitamins) and health problems to your doctor and pharmacist. This will enable them to verify the safety of taking this medication in conjunction with your other treatments and health conditions. Never initiate, terminate, or adjust the dosage of any medication without first consulting 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. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
Certain types of abnormal heart rhythms, as this medication is not suitable for use with many types of irregular heartbeats. If you are unsure, consult your doctor or pharmacist for guidance.
Specific health conditions, including:
+ Fluid accumulation in the lungs
+ Low blood pressure
+ Recent heart attack
Concurrent use of certain medications, such as:
+ Ivabradine
+ Rifampin
This list is not exhaustive, and it is crucial to disclose all your medications (prescription, over-the-counter, natural products, and vitamins) and health problems to your doctor and pharmacist. This will enable them to verify the safety of taking this medication in conjunction with your other treatments and health conditions. Never initiate, terminate, or adjust the dosage 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, get up slowly from a sitting or lying down position, and exercise caution 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 this medication and during treatment. Consult with your doctor regarding the frequency of these checks.
If you have high blood pressure, discuss with your doctor the use of 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, consult with your doctor about potential interactions. Additionally, you may need to avoid consuming alcohol while taking this medication; consult with your doctor or pharmacist to determine if this is necessary.
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. It is crucial to discuss the 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, get up slowly from a sitting or lying down position, and exercise caution 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 this medication and during treatment. Consult with your doctor regarding the frequency of these checks.
If you have high blood pressure, discuss with your doctor the use of 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, consult with your doctor about potential interactions. Additionally, you may need to avoid consuming alcohol while taking this medication; consult with your doctor or pharmacist to determine if this is necessary.
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. It is crucial to discuss the benefits and risks of this medication to both you and your baby.
Overdose Information
Overdose Symptoms:
- Profound hypotension (very low blood pressure)
- Severe bradycardia (very slow heart rate)
- Heart block (impaired electrical conduction in the heart)
- Asystole (cardiac arrest)
- Cardiogenic shock
- Dizziness
- Confusion
- Lethargy
What to Do:
Seek immediate medical attention. Call 911 or your local emergency number. For poison control, call 1-800-222-1222. Treatment may involve gastric lavage, activated charcoal, IV fluids, atropine, calcium gluconate, vasopressors, and/or cardiac pacing.
Drug Interactions
Contraindicated Interactions
- Ivabradine (risk of severe bradycardia)
Major Interactions
- Beta-blockers (e.g., metoprolol, propranolol): Increased risk of bradycardia, AV block, and myocardial depression/heart failure.
- Digoxin: Increased digoxin serum concentrations (monitor digoxin levels).
- Amiodarone: Increased risk of bradycardia, sinus arrest, AV block.
- Statins (e.g., simvastatin, lovastatin): Increased statin concentrations due to CYP3A4 inhibition, leading to increased risk of myopathy/rhabdomyolysis.
- Fentanyl: Increased fentanyl concentrations (CYP3A4 inhibition).
- Dantrolene: Risk of hyperkalemia and myocardial depression (especially with IV dantrolene).
Moderate Interactions
- Other antihypertensives (e.g., ACE inhibitors, ARBs, diuretics): Additive hypotensive effects.
- Alpha-blockers (e.g., prazosin, tamsulosin): Increased risk of orthostatic hypotension.
- Carbamazepine: Increased carbamazepine levels.
- Cyclosporine: Increased cyclosporine levels.
- Theophylline: Increased theophylline levels.
- Midazolam, Triazolam: Increased benzodiazepine levels (CYP3A4 inhibition).
- Grapefruit juice: May increase diltiazem levels (CYP3A4 inhibition).
Minor Interactions
- Cimetidine: May increase diltiazem levels.
- Rifampin: May decrease diltiazem levels.
Monitoring
Baseline Monitoring
Blood Pressure (BP)
Rationale: To establish baseline and guide initial dosing for hypertension/angina.
Timing: Prior to initiation
Heart Rate (HR)
Rationale: To establish baseline and assess for bradycardia risk.
Timing: Prior to initiation
Electrocardiogram (ECG)
Rationale: To assess for pre-existing conduction abnormalities (e.g., AV block, sick sinus syndrome) which are contraindications or require caution.
Timing: Prior to initiation (especially if cardiac history)
Liver Function Tests (LFTs)
Rationale: Diltiazem is extensively metabolized by the liver; baseline assessment is important, especially in patients with hepatic impairment.
Timing: Prior to initiation
Renal Function Tests (RFTs)
Rationale: To assess kidney function, as severe renal impairment may alter drug elimination.
Timing: Prior to initiation
Routine Monitoring
Blood Pressure (BP)
Frequency: Regularly (e.g., weekly during titration, then monthly/quarterly)
Target: Individualized, typically <130/80 mmHg for hypertension
Action Threshold: Persistent hypotension (<90/60 mmHg) or inadequate BP control
Heart Rate (HR)
Frequency: Regularly (e.g., weekly during titration, then monthly/quarterly)
Target: Typically 50-90 bpm (avoiding bradycardia <50 bpm)
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 (e.g., beta-blockers)
Target: Normal PR interval (<0.20 seconds)
Action Threshold: Significant PR prolongation (>0.24 seconds) or development of higher-degree AV block
Signs/Symptoms of Heart Failure (e.g., peripheral edema, dyspnea)
Frequency: At each visit
Target: Absence of new or worsening symptoms
Action Threshold: Development or worsening of heart failure symptoms
Symptom Monitoring
- Dizziness
- Lightheadedness
- Fatigue
- Headache
- Bradycardia (slow heart rate)
- Palpitations
- Shortness of breath
- Swelling in ankles/feet (peripheral edema)
- Constipation
- Rash
Special Patient Groups
Pregnancy
Diltiazem is classified as 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 on the fetus at high doses.
Trimester-Specific Risks:
First Trimester:
Potential for teratogenicity observed in animal studies at high doses; human data are limited but do not conclusively show increased risk.
Second Trimester:
Risk of fetal bradycardia or other cardiac effects, though human data are limited.
Third Trimester:
Risk of fetal bradycardia, hypotension, or other cardiac effects. May inhibit uterine contractions.
Lactation
Diltiazem is excreted into breast milk. The American Academy of Pediatrics considers diltiazem to be compatible with breastfeeding, but caution is advised. Monitor the infant for signs of bradycardia, hypotension, or sedation.
Infant Risk:
Low to moderate risk. Potential for bradycardia, hypotension, or lethargy in the infant. Benefits of breastfeeding should be weighed against potential infant exposure.
Pediatric Use
Safety and effectiveness of diltiazem extended-release formulations have not been established in pediatric patients. Use is generally not recommended.
Geriatric Use
Elderly patients may be more sensitive to the hypotensive and bradycardic effects of diltiazem due to age-related decreases in renal and hepatic function. Start with lower doses and titrate slowly, monitoring closely for adverse effects.
Clinical Information
Clinical Pearls
- Diltiazem is a non-dihydropyridine calcium channel blocker, meaning it affects both vascular smooth muscle and cardiac conduction, unlike dihydropyridines (e.g., amlodipine) which are more vascular selective.
- Extended-release formulations (like Dilacor XR) are designed for once-daily dosing, improving patient adherence.
- It is a good option for patients with both hypertension and angina due to its dual effects.
- Caution is advised when co-administering with beta-blockers due to additive negative chronotropic and dromotropic effects, increasing the risk of severe bradycardia or AV block.
- Patients should be advised not to crush or chew the extended-release capsules, as this can lead to rapid drug release and potentially dangerous side effects.
- Constipation is a common side effect, which can often be managed with dietary fiber and fluids.
Alternative Therapies
- Other Calcium Channel Blockers (e.g., Amlodipine, Felodipine, Nifedipine, Verapamil)
- Beta-blockers (e.g., Metoprolol, Atenolol, Carvedilol)
- ACE Inhibitors (e.g., Lisinopril, Enalapril)
- Angiotensin Receptor Blockers (ARBs) (e.g., Valsartan, Losartan)
- Diuretics (e.g., Hydrochlorothiazide, Furosemide)
- Nitrates (for angina, e.g., Isosorbide mononitrate, Nitroglycerin)
Cost & Coverage
Average Cost:
Varies widely, typically $10-$100+ per 30 capsules (generic)
Generic Available:
Yes
Insurance Coverage:
Tier 1 or Tier 2 (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.