Diltiazem Pharmacology


About Diltiazem
A Benzothiazepine derivative, Calcium channel blocker, Anti hypertensive, anti-anginal, class IV antiarrhythmic.
Mechanism of Action of Diltiazem
Diltiazem is a Benzothiazepine; Ca channel blocker. It exerts it`s antianginal, antihypertensive, antiarrythmic actions through blocking the influx of Ca ions through voltage gated L-type Ca channels to the peripheral vascular smooth muscle cells, Coronary smooth muscle cells and to the myocardial cells. Thus causes dilatation of vascular endothelium, decrease peripheral resistance, and decrease BP in hypertensive individuals.
It increases exercise tolerance and reduce myocardial oxygen demand in angina patients. It acts as a coronary artery dilator inhibits coronary artery spasm and improves coronary blood flow. It interferes with depolarization and decreases SA node automaticity. It prolongs AV nodal effective refractory period and increases PR interval. It decreases heart rate and increases cardiac out put. It markedly relaxes arterioles and milder effects on veins. It do not compromise haemodynamics and cerebral and renal perfusion.

Pharmacokinets of Diltiazem
Absorption: Well absorbed orally, bioavailability is reduced due to first pass metabolism.
Distribution: Widely distributed in a protein bound form.
Metabolism: Metabolized in liver, and there is active metabolite.
Excretion: Excreted through urine.
Onset of Action for Diltiazem
I.V.:2 to 5 minutes
Oral: 2 to 4 hours
Duration of Action for Diltiazem
8 to 12 hours
Half Life of Diltiazem
5 to 6 hours
Side Effects of Diltiazem
1. Palpitation
2. Flushing
3. Nausea
4. Diarrhoea
5. Pain
6. Edema
7. Bradycardia
8. A-V block
9. Headache
10. Dizziness
11. Vasodilatation
12. Rashes
13. Dyspepsia
14. Pharyngitis
15. Bronchitis
16. Nervousness

Contra-indications of Diltiazem
1. Heart failure
2. 2nd and 3rd degree Heart block
3. Sick sinus syndrome
4. Hypersensitivity to the drug
5. Unstable angina
6. Hepatic impairment
7. Renal impairment
8. Porphyria
Special Precautions while taking Diltiazem
1. Bradycardia
2. Hypotension
3. Impaired left ventricular function
4. Congestive heart failure
5. Use cautiously along with other antihypertensive drugs
6. Use with caution along with digitalis and other antiarrythmic drugs
7. Slowly withdraw the drug with caution
8. Diabetes mellitus
9. Long term use
Pregnancy Related Information
Old Age Related Information
Use with caution
Breast Feeding Related Information
Use with caution
Children Related Information
Indications for Diltiazem
1. Hypertension
2. Prinzmetal`s angina
3. Stable angina

Interactions for Diltiazem
Cimetidine & Ranitidine: Enhance the efficacy of diltiazem.
?-Blockers: Though advantageous in some, concomitant use may result in increased adverse effects like bradycardia and conduction disturbances.
Carbamazepine, Cyclosporin, Digitalis Glycosides: Efficacy of these drugs increased with possible toxicity.
Theophylline: Increased efficacy of theophylline.
Typical Dosage for Diltiazem
120 to 240mg/day.
Prinzmetal`s angina and Stable angina: 120 to 180mg/day. Single or in 3 to 4 divided doses.
Maximum dose: 360mg/day.
Hypertension: 120 to 240mg/day. Single or in 3 to 4 divided doses.
Maximum dose: 360mg/day.
Schedule of Diltiazem
Storage Requirements for Diltiazem
Store in a cool dry place below 25 degree C. Protect from moisture and light.
Effects of Missed Dosage of Diltiazem
Take the missed dose as soon as noticed and if it is the time for next dose then skip the missed dose. Continue the regular schedule. Do not double the dose.
Effects of Overdose of Diltiazem
Treatment is supportive and symptomatic. Remove drug from the stomach by gastric lavage. Monitor & support cardiac and respiratory functions. Measure the BP. Give cardiovascular support by elevating the limbs and maintaining fluid balance. Administer vasopressers like nor epinephrine if required to treat hypotension. Treat Bradycardia with atropine. Administer isoproterenol with caution if required. Treat heart block with cardiac pacing. Treat cardiac failure with ionotropic agents such as isoproterenol, dopamine, dobutamine etc and diuretics.

Home Delivery for Diltiazem in Your City

Medicine India is just a publishing medium for medicine related information and does not provide services or sales of medicines including diltiazem.

However, we do publish a comprehensive directory of Pharmacies, Chemists and Druggists in cities all over India. You can use this directory to find the medicine stores in your city (or area) that provide home delivery services for diltiazem and other medicines and health products. Home delivery services for diltiazem may be free or they may cost you depending on the pharmacy and the minimum order requirements. It would be best to get this clarified while placing the order.

Please be aware that you should take diltiazem only if a doctor has recommended or prescribed it. Some or all pharmacies who provide a home delivery service for medicines might insist on a prescription for diltiazem before they complete the sale. You can get this information while placing the order for diltiazem with the pharmacy.

Diltiazem is a generic medicine name and there are several brands available for it. Some of the brands for diltiazem might be better known than diltiazem itself. If the pharmacy that's willing to deliver medicines to your home doesn't have diltiazem in stock, you can ask for one of the branded alternatives for diltiazem.