Rifampicin Pharmacology


About Rifampicin
Rifamycin derivative, Antituberculosis antibiotic.
Mechanism of Action of Rifampicin
Rifampicin is primarily bactericidal and has some bacteriostatic properties also. It acts by inhibiting DNA dependent RNA polymerase and thus stopping the expression of bacterial genes.M.tuberculosis requires DNA dependent RNA polymerase enzyme for the synthesis of RNA and protein. Without this enzyme bacteria cannot reproduce and they die.

Pharmacokinets of Rifampicin
Absorption: Well absorbed orally, Distribution: Widely distributed, Metabolism: Metabolized in liver in to active desacetyl Rifampicin Excretion: Excreted mainly in bile & some extend in urine
Onset of Action for Rifampicin
Duration of Action for Rifampicin
24 hours
Half Life of Rifampicin
2 - 5 hour
Side Effects of Rifampicin
1. Nausea
2. Vomiting
3. Epigastric distress
4. Anorexia
5. Pseudo membranous colitis
6. Acute renal failure
7. Hepato toxicity
8. Eosinophilia
9. Thrombocytopenia
10. Urticaria
11. Rash
12. Pruritis
13. Purpura
14. Shock
15. Headache
16. Drowsiness
17. Visual disturbance
18. Thrombophlebitis
19. Menstrual problems
Contra-indications of Rifampicin
1.Hypersensitivity to the drug
2.Hepatic impairment
4.Biliary obstruction
6.As I.M. or S.C. injection
Special Precautions while taking Rifampicin
Renal impairment:
Use with caution
Hepatic impairment:
Use with caution
Other precautions:
1.Use with caution in alcoholics
2.Use with caution in malnourished individuals
3.Stop the drug use in Purpura & Thrombocytopenia
Pregnancy Related Information
Use with caution
Old Age Related Information
Use with caution
Breast Feeding Related Information
Use with caution
Children Related Information
Above 5 years: May be used
Neonates: Contraindicated
Indications for Rifampicin
1. Leprosy
2. Tuberculosis
3. Prophylaxis of meningococcal carriers
4. Prophylaxis of H. influenzae
Interactions for Rifampicin
Rifampicin by inducing the hepatic microsomal enzymes may reduce the efficacy of the following drugs: Acetaminophen, oral anticoagulants, barbiturates, benzodiazepines, chloramphenicol, clofibrate. Oral contraceptives, corticosteroids, cyclosporine, digitoxin, disopyramide, beta blockers oestrogens, hydantoins, mexiletine, quinidine, sulfones, sulphonylureas, theophylline, verapamil.
Halothane: Hepatotoxicity and hepatic encephalopathy.
Isoniazid: Higher incidence of hepatotoxicity than with either agent alone.
Ketoconazole: Treatment failure of either ketoconazole or rifampicin.
Food: Interferes with absorption of rifampicin, therefore it should be taken on empty stomach.
Lab tests: Inhibits standard assays for serum folate and vitamin B12 (riboflavin). Transient abnormalities in liver function tests, reduced excretion of contrast media used for visualization of gall bladder.

Typical Dosage for Rifampicin
Adults: 0.45gm to 0.6gm single dose
Children: 10 to 20 mg/kg/day
Leprosy: 600mg orally once monthly
Pulmonary tuberculosis:
Adults: 600mg/day orally or I.V. as a single dose
Children: 10 to 20 mg/kg/day orally or I.V.as a single dose
Meningococcal infections:
600mg 12 hourly for two days
Children (1 to 2 years): 10 mg/kg
Children (below 1 year): 5mg/kg for two days

Schedule of Rifampicin
Storage Requirements for Rifampicin
Store in a cool dry place.Protect from heat and light.Keep out of the reach of children.
Effects of Missed Dosage of Rifampicin
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 Rifampicin
Treatment includes Gastric lavage, administration of activated charcoal, forced diuresis & bile drainage etc.

Home Delivery for Rifampicin in Your City

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

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 rifampicin and other medicines and health products. Home delivery services for rifampicin 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 rifampicin 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 rifampicin before they complete the sale. You can get this information while placing the order for rifampicin with the pharmacy.

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