Rifampicin

MOA

Drug Label Information | Brands:

Brands of Rifampicin

Macox® , Macleods Pharmaceuticals Limited
R-cin®, Lupin Limited
Rifacos®, Cosmos Limited
Rifampicin, Elys
Unirif®, Universal Corporation Limited

INDICATIONS:

Tuberculosis: Rifampicin, used in combination with other active anti-tuberculosis drugs, is indicated in the treatment of all forms of tuberculosis, including fresh, advanced, chronic and drug-resistant cases. Rifampicin is also effective against most atypical strains of mycobacteria.

Prophylaxis of meningococcal meningitis: Prophylaxis of meningococcal meningitis in close contact adult and paediatric patients.

Leprosy: Rifampicin is indicated in the combination treatment of multibacillary and paucibacillary leprosy in patients of all age groups.

Haemophilus influenzae: Propylaxis of Haemophilus influenzae type b disease in close contacts.

Other infections: Rifampicin is indicated in the treatment of brucellosis, legionnaires disease, and serious staphylococcal infections. Rifampicin should be used in combination with another appropriate antibiotic to prevent emergence of resistant strains of the infecting organism.

DOSAGE AND ADMINISTRATION:

Tuberculosis

Rifampicin should be given with other effective anti-tuberculosis drugs to prevent the possible emergence of rifampicin resistant strains of mycobacteria.

Adults: The recommended single daily dose in tuberculosis is 8-12mg/kg.

Usual daily dose:

Patients weighing less than 50kg – 450mg

Patients weighing 50kg or more – 600mg

Paediatric patients:

Children above 3 months: Oral doses of 15 (10-20) mg/kg body weight daily are recommended, although a total daily dose should not usually exceed 600mg.

Prophylaxis of Meningococcal Meningitis

Adults: 600mg twice daily for 2 days.

Paediatric patients:

Meningococcal Carriers: Dose must not exceed 600 mg/ dose.

For children ≥1 month of age the recommended dose is 10 mg/kg every 12 hours for 2 days.

For children <1 month of age, the recommended dose is 5 mg/kg every 12 hours for 2 days.

Leprosy

Rifampicin should always be used in conjunction with at least one other anti-leprosy drug to treat the disease.

Adults:

600mg of rifampicin should be given once per month. If a daily dose regime is indicated then the recommended single dose is 10mg/kg. The usual daily dose for patients less than 50kg is 450mg and for patients 50kg or more, the usual daily dose is 600mg.

Paediatric patients:

Rifampicin should always be administered with dapsone in case of paucibacillary forms and with dapsone and clofazimine in case of multibacillary forms.

For children over 10 years, the recommended dose for rifampicin is 450 mg once a month.

For children less than 10 years, the recommended dose for rifampicin is 10 to 20 mg/kg rifampicin once a month.

The duration of treatment is 6 months for paucibacillary and 12 months multibacillary forms.

Prophylaxis of Haemophilus Influenzae

Adults and children ≥1 month of age:

For members of a household exposed to H. Influenzae B disease when the household contains a child 4 years old or younger, it is recommended that all members (including the child) receive 20mg/kg once daily (maximum daily dose of 600mg) for 4 days.

Index cases should be treated prior to discharge from hospital.

For children <1 month of age: 10mg/kg once daily for 4 days

Brucellosis, Legionnaires Disease or Serious Staphylococcal Infections

Adults:

The recommended daily dose is 600mg to 1200mg given in 2 to 4 divided doses, together with another appropriate antibiotic to prevent the emergence of resistant strains of the infecting organism.

Patients with impaired liver function

A daily dose of 8mg/kg should not be exceeded in patients with impaired liver function.

Use in the Elderly

In elderly patients, the renal excretion of rifampicin is decreased proportionally with physiological decrease of renal function; due to compensatory increase of liver excretion, the serum terminal half-life is similar to that of younger patients. However, as increased blood levels have been noted in one study of rifampicin in elderly patients, caution should be exercised in using rifampicin in such patients, especially if there is evidence of liver function impairment.

CONTRAINDICATIONS:

Rifampicin is contraindicated in the presence of jaundice, and in patients who are hypersensitive to the active substance, rifampicin.

Rifampicin is contraindicated when given concurrently with the combination of saquinavir/ ritonavir

ADVERSE DRUG REACTIONS:

Skin and subcutaneous tissue disorders

Cutaneous reactions which are mild and self-limiting may occur and do not appear to be hypersensitivity reactions. Typically, they consist of flushing and itching with or without a rash. Urticaria and more serious hypersensitivity cutaneous reactions have occurred but are uncommon. Exfoliate dermatitis, pemphigoid reaction, erythema multiforme including Stevens-Johnson syndrome, Lyells syndrome and vasculitis have been reported rarely.

Gastrointestinal disorders

Gastrointestinal reactions consist of anorexia, nausea, vomiting, abdominal discomfort, and diarrhoea. Pseudomembranous colitis has been reported with rifampicin therapy.

Hepatobiliary disorders

Hepatitis can be caused by rifampicin and liver function tests should be monitored (see section 4.4).

Nervous system disorders

Central Nervous system: Psychoses have been rarely reported.

Vascular disorders

Thrombocytopenia with or without purpura may occur, usually associated with intermittent therapy, but is reversible if drug is discontinued as soon as purpura occurs. Cerebral haemorrhage and fatalities have been reported when rifampicin administration has been continued or resumed after the appearance of purpura.

Disseminated intravascular coagulation has also been rarely reported.

Blood and lymphatic system disorders

Eosinophilia, leucopenia, oedema have been reported to occur in a small percentage of patients treated with rifampicin.

Agranulocytosis has been very rarely reported.

Musculoskeletal and connective tissue disorders

Muscle weakness and myopathy have been reported to occur in a small percentage of patients treated with rifampicin.

Immune system disorders

Reactions usually occurring with intermittent dosage regimens and most probably of immunological origin include:

– ‘Flu Syndrome’ consisting of episodes of fever, chills, headache, dizziness, and bone pain appearing most commonly during the 3rd to the 6th month of therapy. The frequency of the syndrome varies but may occur in up to 50% of patients given once-weekly regimens with a dose of rifampicin of 25mg/kg or more.

– Shortness of breath and wheezing

– Decrease in blood pressure and shock

– Anaphylaxis

– Acute haemolytic anaemia

– Acute renal failure usually due to acute tubular necrosis or to acute interstitial nephritis.

General disorders and administration site conditions

If serious complications arise, e.g. renal failure, thrombocytopenia or haemolytic anaemia, rifampicin should be stopped and never restarted.

Occasional disturbances of the menstrual cycle have been reported in women receiving long term anti-tuberculosis therapy with regimens containing rifampicin.

Rifampicin may produce a reddish discolouration of the urine, sweat, sputum and tears. The patient should be forewarned of this. Soft contact lenses may be permanently stained.

DRUG INTERACTIONS:

Cytochrome P-450 enzyme interaction

Rifampicin is a potent inducer of certain cytochrome P-450 enzymes. Coadministration of rifampicin with other drugs that are also metabolised through these cytochrome P-450 enzymes may accelerate the metabolism and reduce the activity of these other drugs. Therefore, caution should be used when prescribing rifampicin with drugs metabolised by cytochrome P-450. To maintain optimum therapeutic blood levels, dosages of drugs metabolised by these enzymes may require adjustment when starting or stopping concomitantly administered rifampicin. Examples of drugs metabolised by cytochrome P-450 enzymes are:

• Antiarrhythmics (e.g. disopyramide, mexiletine, quinidine, propafenone, tocainide)

• Antiepileptics (e.g. phenytoin)

• Hormone antagonist (antiestrogens e.g. tamoxifen, toremifene, gestinone)

• Antipsychotics (e.g. haloperidol, aripiprazole)

• Anticoagulants (e.g. coumarins)

• Antifungals (e.g. fluconazole, itraconazole, ketoconazole, voriconazole)

• Antivirals (e.g. saquinavir, indinavir, efavirenz, amprenavir, nelfinavir, atazanavir, lopinavir, nevirapine)

• Barbiturates

• Beta-blockers (e.g. bisoprolol, propanolol)

• Anxiolytics and hypnotics (e.g. diazepam, benzodiazepines, zopiclone, zolpidem),

• Calcium channel blockers (e.g. diltiazem, nifedipine, verapamil, nimodipine, isradipine, nicardipine, nisoldipine)

• Antibacterials (e.g. chloramphenicol, clarithromycin, dapsone, doxycycline, fluoroquinolones, telithromycin)

• Corticosteroids

• Cardiac glycosides (digitoxin, digoxin)

• Clofibrate

• Systemic hormonal contraceptives

• Oestrogen

• Antidiabetic (e.g. chlorpropamide, tolbutamide, sulfonylureas, rosiglitazone)

• Immunosuppressive agents (e.g. ciclosporin, sirolimus, tacrolimus)

• Irinotecan

• Thyroid hormone (e.g. levothyroxine)

• Losartan

• Analgesics (e.g. methadone, narcotic analgesics)

• Praziquantel

• Progestogens

• Quinine

• Riluzole

• Selective 5-HT3 receptor antagonists (e.g. ondansetron)

• Statins metabolised by CYP 3A4 (e.g. simvastatin)

• Theophylline

• Tricyclic antidepressants (e.g. amitriptyline, nortriptyline)

• Cytotoxics (e.g. imatinib)

• Diuretics (e.g. eplerenone)

Patients on oral contraceptives should be advised to use alternative, non-hormonal methods of birth control during rifampicin therapy. Also diabetes may become more difficult to control.

When rifampacin is give concomitantly with the combination saquinavir/ritonavir, the potential for hepatotoxicity is increased. Therefore, concomitant use of rifampacin with saquinavir/ritonavir is contraindicated (see section 4.3).

When the two drugs were taken concomitantly, decreased concentrations of atovaquone and increased concentrations of rifampicin were observed.

Concurrent use of ketoconazole and rifampicin has resulted in decreased serum concentrations of both drugs.

Concurrent use of rifampicin and enalapril has resulted in decreased concentrations of enalaprilat, the active metabolite of enalapril. Dosage adjustments should be made if indicated by the patient’s clinical condition.

Concomitant antacid administration may reduce the absorption of rifampicin. Daily doses of rifampicin should be given at least 1 hour before the ingestion of antacids.

When rifampicin is given concomitantly with either halothane or isoniazid, the potential for hepatotoxicity is increased. The concomitant use of rifampicin and halothane should be avoided. Patients receiving both rifampicin and isoniazid should be monitored closely for hepatotoxicity.

If p-aminosalicylic acid and rifampicin are both included in the treatment regimen, they should be given not less than eight hours apart to ensure satisfactory blood levels.

Interference with laboratory and diagnostic tests

Therapeutic levels of rifampicin have been shown to inhibit standard microbiological assays for serum folate and Vitamin B12. Thus alternative assay methods should be considered. Transient elevation of BSP and serum bilirubin has been reported. Rifampicin may impair biliary excretion of contrast media used for visualization of the gallbladder, due to competition for biliary excretion. Therefore, these tests should be performed before the morning dose of rifampicin.