Rifadin, Rimactane, Rofact
Classifications: antibiotic; antituberculosis agent; Therapeutic: 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.
Active against Mycobacterium tuberculosis, M. leprae, Neisseria meningitidis, and a wide range of gram-negative and gram-positive organisms.
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.
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; pregnancy
(category C). Safe use in children <5 y is not established.
Hepatic disease; history of alcoholism; concomitant use of other hepatotoxic agents.
Route & Dosage
Adult: PO/IV 600 mg daily in conjunction with other antituberculosis agents
Child: PO/IV 1020 mg/kg/d (max: 600 mg/d)
Adult: PO 600 mg q12h for 2 consecutive days
Child: PO 1020 mg/kg q12h for 2 consecutive days (max: 600 mg/d)
Prophylaxis for H. influenzae Type B
Adult: PO 600 mg/d for 4 d
Child: PO 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
- Give 1 h before or 2 h after a meal. Peak serum levels are delayed and may be slightly lower when given with food; capsule
contents may be emptied into fluid or mixed with food.
- Note: An oral suspension can be prepared from capsules for use with pediatric patients. Consult pharmacist for directions.
- Keep a desiccant in bottle containing capsules to prevent moisture causing instability.
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 of D5W (preferred) or NS. If absolutely necessary, 100 mL of D5W or NS may
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.
- Use NS solutions within 24 h and D5W solutions within 4 h of preparation.
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
Hemoglobinuria, hematuria, acute renal failure,
light-chain proteinuria, menstrual disorders
, hepatorenal syndrome,
(with intermittent therapy). Respiratory:
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.
InteractionsDrug: Alcohol, isoniazid, pyrazinamide
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
, 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,
leading to potential therapeutic failure.
Readily from GI tract. Peak:
24 h. Distribution:
Widely distributed, including CSF; crosses placenta; distributed into breast milk. Metabolism:
In liver to active and inactive metabolites; is enterohepatically cycled. Elimination:
Up to 30% in urine, 6065% in feces. Half-Life:
Assessment & Drug Effects
- Lab tests: Periodic liver function tests are advised. Closely monitor patients with hepatic disease.
- Check prothrombin time daily or as necessary to establish and maintain required anticoagulant activity when patient is also
receiving an anticoagulant.
Patient & Family Education
- Do not interrupt prescribed dosage regimen. Hepatorenal reaction with flu-like syndrome has occurred when therapy has been
resumed following interruption.
- Be aware that drug may impart a harmless red-orange color to urine, feces, sputum, sweat, and tears. Soft contact lenses
may be permanently stained.
- Report onset of jaundice, hypersensitivity reactions, and persistence of GI adverse effects to physician.
- Use or add barrier contraceptive if using hormonal contraception. Concomitant use of rifampin and oral contraceptives leads
to decreased effectiveness of the contraceptive and to menstrual disturbances (spotting, breakthrough bleeding).
- Keep drug out of reach of children.