Rifampin, Isoniazid, Pyrazinamide, and Ethambutol (Systemic)

Before Using This Medicine

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For rifampin, isoniazid, pyrazinamide, and ethambutol combination, the following should be considered:

Allergies - Tell your doctor if you have ever had any unusual or allergic reaction to ethionamide (e.g., Trecator-SC), pyrazinamide, niacin (e.g., Nicobid, nicotinic acid), rifampin (e.g., Rifadin), rifabutin (e.g., Mycobutin), rifapentine (e.g., Priftin), isoniazid (e.g., INH, Nydrazid), or ethambutol (e.g., Myambutol). Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy - Pregnant women with tuberculosis (TB) should be treated with TB medicines, including rifampin, isoniazid, pyrazinamide, and ethambutol. Rifampin, isoniazid, pyrazinamide, and ethambutol combination has not been shown to cause birth defects or other problems in humans. However, rifampin can rarely cause bleeding in newborn babies and mothers when taken during the last weeks of pregnancy. Also, studies in rats and mice have shown that rifampin given in high doses causes birth defects, usually backbone problems (spina bifida) and cleft palate.

Breast-feeding - Rifampin, isoniazid, pyrazinamide, and ethambutol pass into the breast milk. However, rifampin, isoniazid, pyrazinamide, and ethambutol have not been reported to cause problems in nursing babies.

Children - Rifampin, isoniazid, pyrazinamide, and ethambutol combination may not be appropriate for use in children weighing under 30 kilograms (kg) (66 pounds).

Older adults - Liver problems are more likely to occur in patients over 50 years of age who are taking isoniazid-containing medicines.

Other medicines - Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking rifampin, isoniazid, pyrazinamide, and ethambutol combination, it is especially important that your health care professional know if you are taking any of the following:

• Acetaminophen (e.g., Tylenol) (with long-term, high-dose use) or
• Alfentanil (e.g., Alfenta) or
• Amiodarone (e.g., Cordarone) or
• Anabolic steroids (nandrolone [e.g., Anabolin], oxandrolone [e.g., Anavar], oxymetholone [e.g., Anadrol], stanozolol [e.g., Winstrol]) or
• Androgens (male hormones) or
• Antithyroid agents (medicine for overactive thyroid) or
• Carbamazepine (e.g., Tegretol)
• Carmustine (e.g., BiCNU) or
• Chloroquine (e.g., Aralen) or
• Dantrolene (e.g., Dantrium) or
• Daunorubicin (e.g., Cerubidine) or
• Divalproex (e.g., Depakote) or
• Etretinate (e.g., Tegison) or
• Gold salts (medicine for arthritis) or
• Hydroxychloroquine (e.g., Plaquenil) or
• Mercaptopurine (e.g., Purinethol) or
• Methyldopa (e.g., Aldomet) or
• Naltrexone (e.g., Trexan) (with long-term, high-dose use) or
• Phenothiazines (acetophenazine [e.g., Tindal], chlorpromazine [e.g., Thorazine], fluphenazine [e.g., Prolixin], mesoridazine [e.g., Serentil], perphenazine [e.g., Trilafon], prochlorperazine [e.g., Compazine], promazine [e.g., Sparine], promethazine [e.g., Phenergan], thioridazine [e.g., Mellaril], trifluoperazine [e.g., Stelazine], triflupromazine [e.g., Vesprin], trimeprazine [e.g., Temaril]) or
• Plicamycin (e.g., Mithracin) or
• Valproic acid (e.g., Depakene) - These medicines may increase the chance of liver damage if taken with rifampin, isoniazid, and pyrazinamide combination

• Aminophylline (e.g., Somophyllin) or
• Amprenavir (e.g., Agenerase) or
• Anticoagulants (blood thinners) or
• Antidiabetics, oral (diabetes medicines you take by mouth) or
• Chloramphenicol or
• Corticosteroids (cortisone-like medicine) or
• Delavirdine (e.g., Rescriptor) or
• Digitalis glycosides (heart medicine) or
• Disopyramide (e.g., Norpace) or
• Efavirenz (e.g., Sustiva) or
• Estramustine (e.g., Emcyt) or
• Fluconazole (e.g., Diflucan) or
• Indinavir (e.g., Crixivan) or
• Itraconazole (e.g., Sporanox) or
• Ketoconazole (e.g., Nizoral) or
• Methadone (e.g., Dolophine) or
• Methotrexate (e.g., Mexate) or
• Mexiletine (e.g., Mexitil) or
• Nelfinavir (e.g., Viracept) or
• Nevirapine (e.g., Viramune) or
• Oxtriphylline (e.g., Choledyl) or
• Quinidine (e.g., Quinidex) or
• Ritonavir (e.g., Norvir) or
• Saquinavir (e.g., Fortovase, Invirase) or
• Theophylline (e.g., Theo-Dur, Somophyllin-T) or
• Tocainide (e.g., Tonocard) or
• Verapamil (e.g., Calan) - Rifampin, isoniazid, pyrazinamide, and ethambutol combination may decrease the effects of these medicines

• Disulfiram (e.g., Antabuse) - This medicine may increase the chance of liver damage and side effects, such as dizziness, lack of coordination, irritability, and inability to sleep

• Estrogens (female hormones) or
• Oral contraceptives (birth control pills) containing estrogen or
• Phenytoin (e.g., Dilantin) - Rifampin, isoniazid, pyrazinamide, and ethambutol combination may decrease the effects of these medicines. If you are taking oral contraceptives, this may increase the chance of pregnancy. These medicines may also increase the chance of liver damage if taken with rifampin, isoniazid, pyrazinamide, and ethambutol combination

Other medical problems - The presence of other medical problems may affect the use of rifampin, isoniazid, pyrazinamide, and ethambutol combination. Make sure you tell your doctor if you have any other medical problems, especially:

• Alcohol abuse (or history of) or
• Liver disease - There may be an increased chance of getting hepatitis if you take this medicine and drink alcohol daily

• Convulsive disorders such as seizures or epilepsy - This medicine may increase the frequency of convulsions (seizures) in some patients

• Gout (history of) - This medicine may worsen or cause a gout attack in patients with a history of gout

• Kidney disease (severe) - There may be an increased chance of side effects in patients with severe kidney disease