Rifadin, Rimactane, Rofact 
Classifications: antiinfective; antibiotic; antituberculosis agent
Pregnancy Category: C


150 mg, 300 mg capsules; 600 mg injection


Semisynthetic derivative of rifamycin B, an antibiotic derived from Streptococcus mediterranei, with bacteriostatic and bactericidal actions. Inhibits DNA-dependent RNA polymerase activity in susceptible bacterial cells, thereby suppressing RNA synthesis.

Therapeutic Effects

Active against Mycobacterium tuberculosis, M. leprae, Neisseria meningitidis, and a wide range of gram-negative and gram-positive organisms. It is used in conjunction with other antitubercular agents to treat tuberculosis because resistant strains emerge rapidly when it is employed alone.


Primarily as adjuvant with other antituberculosis agents in initial treatment and retreatment of clinical tuberculosis; as short-term therapy to eliminate meningococci from nasopharynx of asymptomatic carriers of N. meningitidis when risk of meningococcal meningitis is high.

Unlabeled Uses

Chemoprophylaxis in contacts of patients with Haemophilus influenzae type B infection; alone or in combination with dapsone and other antiinfectives in treatment of leprosy (especially dapsone-resistant leprosy). Also infections caused by susceptible gram-negative and gram-positive bacteria that fail to respond to other antiinfectives; in combination with erythromycin or tetracycline for treatment of Legionnaire's disease.


Hypersensitivity to rifampin; obstructive biliary disease; meningococcal disease; intermittent rifampin therapy; lactation. Safe use during pregnancy (category C) or in children <5 y is not established.

Cautious Use

Hepatic disease; history of alcoholism; concomitant use of other hepatotoxic agents.

Route & Dosage

Pulmonary Tuberculosis
Adult: PO/IV 600 mg once/d in conjunction with other antituberculosis agents
Child: PO 10–20 mg/kg/d (max: 600 mg/d)

Meningococcal Carriers
Adult: PO 600 mg b.i.d. for 2 consecutive d
Child: PO 10–20 mg/kg b.i.d. for 2 consecutive d (max: 600 mg/d)

Prophylaxis for H. influenzae Type B
Adult: PO 600 mg/d for 4 d
Child: PO 10–20 mg/kg/d for 4 d (max: 600 mg/d)

Dapsone-Sensitive Multibacillary Leprosy
Adult: PO 600 mg once/mo with clofazimine and dapsone for a minimum of 2 y



PREPARE: IV Infusion: Dilute by adding 10 mL of sterile water for injection to each 600-mg vial to yield 60 mg/mL. Swirl to dissolve. Withdraw the ordered dose and further dilute in 500 mL (preferred) of D5W. If necessary, 100 mL of D5W may be used.  

ADMINISTER: IV Infusion: Infuse 500 mL solution over 3 h and 100 mL solution over 30 min. Note: A less concentrated solution infused over a longer period is preferred.  

INCOMPATIBILITIES Solution/additive: Minocycline. Y-site: Diltiazem.

Adverse Effects (1%)

CNS: Fatigue, drowsiness, headache, ataxia, confusion, dizziness, inability to concentrate, generalized numbness, pain in extremities, muscular weakness. Special Senses: Visual disturbances, transient low-frequency hearing loss, conjunctivitis. GI: Heartburn, epigastric distress, nausea, vomiting, anorexia, flatulence, cramps, diarrhea, pseudomembranous colitis, transient elevations in liver function tests (bilirubin, BSP, alkaline phosphatase, ALT, AST), pancreatitis. Hematologic: Thrombocytopenia, transient leukopenia, anemia, including hemolytic anemia. Body as a Whole: Hypersensitivity (fever, pruritus, urticaria, skin eruptions, soreness of mouth and tongue, eosinophilia, hemolysis), flu-like syndrome. Urogenital: Hemoglobinuria, hematuria, acute renal failure, light-chain proteinuria, menstrual disorders, hepatorenal syndrome, (with intermittent therapy). Respiratory: Hemoptysis. Other: Increasing lethargy, liver enlargement and tenderness, jaundice, brownish-red or orange discoloration of skin, sweat, saliva, tears, and feces; unconsciousness.

Diagnostic Test Interference

Rifampin interferes with contrast media used for gallbladder study; therefore, test should precede daily dose of rifampin. May also cause retention of BSP. Inhibits standard assays for serum folate and vitamin B12.


Drug: Alcohol, isoniazid, pyrazinamide, ritonavir, saquinavir increase risk of drug-induced hepatotoxicity (including fatal hepatotoxicity when used for latent TB); p-aminosalicylic acid (PAS) decreases concentrations of rifampin; decreases concentrations of alfentanil, alosetron, alprazolam, amprenavir, barbiturates, benzodiazepines, carbamazepine, atovaquone, cevimeline, chloramphenicol, clofibrate, corticosteroids, cyclosporine, dapsone, delavirdine, diazepam, digoxin, diltiazem, disopyramide, estazolam, estramustine, fentanyl, fosphenytoin, fluconazole galantamine, indinavir, itraconazole, ketoconazole, lamotrigine, levobupivacaine, lopinavir, methadone, metoprolol, mexiletine, midazolam, nelfinavir, oral sulfonylureas, oral contraceptives, phenytoin, progestins, propafenone, propranolol, quinidine, quinine, ritonavir, sirolimus, theophylline, thyroid hormones, tocainide, tramadol, verapamil, warfarin, zaleplon, and zonisamide, leading to potential therapeutic failure.


Absorption: Readily absorbed from GI tract. Peak: 2–4 h. Distribution: Widely distributed, including CSF; crosses placenta; distributed into breast milk. Metabolism: Metabolized in liver to active and inactive metabolites; is enterohepatically cycled. Elimination: Up to 30% excreted in urine, 60–65% in feces. Half-Life: 3 h.

Nursing Implications

Assessment & Drug Effects

Patient & Family Education

Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug