Rifadin (Rifampin) Dosage and Side Effects
RIFADIN is an antibiotic used to treat bacterial infections. RIFADIN is in a class of drugs called antimycobacterials. It kills bacteria by blocking the activity of an enzyme the bacteria need to reproduce and survive.
It's approved to treat all forms of tuberculosis (TB) caused by Mycobacterium tuberculosis, including latent TB infections. RIFADIN is also used to eliminate meningitis-causing Neisseria meningitidis from the nose and throat of people who don't have symptoms so they don't spread the infection to others.
Proper Use of this medication
RIFADIN comes as oral capsules or in solution for intravenous use.
For treating adults with TB, RIFADIN should be taken once daily with a full glass of water, either an hour before a meal or two hours afterward.
The initial phase of treatment requires it to be taken with isoniazid and pyrazinamide, for two months. A fourth drug, either streptomycin or ethambutol, may also be necessary.
Following this initial course, doctors prescribe another four months of treatment with RIFADIN and isoniazid.
If you are taking RIFADIN, you must complete the treatment course, even if you feel better. Completing the treatment ensures that the bacteria causing the infection are completely eradicated and don't become resistant.
The drug is taken twice daily for two days to treat N. meningitidis infection in adults.
Symptoms of overdose include:
- Nausea and vomiting
- Abdominal pain
- Severe itching
- Increased lethargy
- Jaundice and liver enlargement
Children who overdose may also experience facial sweating and some life-threatening symptoms, including low blood pressure, irregular heartbeat, seizures, and heart attacks.
Contact a poison control center or emergency room if you suspect you have taken too much RIFADIN. Call 911 if a person has collapsed or isn't breathing.
Missed Dose of RIFADIN
Missing a dose of RIFADIN can increase your risks of developing low blood platelet counts and a hypersensitivity to the drug in your kidneys.
Take the missed dose as soon as you remember it. But if it's almost time for your next dose, skip the missed dose and call your doctor.
Common Side Effects of RIFADIN:
- Upset stomach and cramps
- Inability to concentrate
- Confusion and behavioral changes
- Muscular weakness, pain in your arms or legs, and generalized numbness
- Vision changes
- Painful or irregular menstruation
- Flushing and itchiness
- Lack of coordination
Severe Side Effects of RIFADIN
Contact your doctor if you experience any of the following:
- Loss of appetite
- Nausea and vomiting
- Darkened urine
- Jaundice (yellowing of the skin and eyes)
- Pain or swelling of your joints
Rare Side Effects of RIFADIN:
The following side effects have been reported but are rare:
- Myopathy (muscular disease)
- Adrenal insufficiency (inadequate amounts of steroid hormones in people with compromised adrenal glands)
- Kidney issues
- Hepatitis (liver inflammation, usually caused by a viral infection) and abnormal liver function
Warnings and Precautions
You shouldn't take the RIFADIN if you are hypersensitive to it, any of its components, or related antibiotics (rifamycins).
Some antiviral medications reduce the effectiveness of RIFADIN, including:
- Darunavir (Prezista)
- Atazanavir (Reyataz)
- Fosamprenavir (Lexiva)
- Saquinavir (Invirase)
- Tipranavir (Aptivus)
Taking RIFADIN with ritonavir-boosted saquinavir (Invirase), an HIV-antiviral drug, could increase your risk of severe liver damage.
Your doctor will not prescribe RIFADIN if you have symptoms of meningitis. That's because the medication increases your risk of rapidly developing a resistant strain of the bacteria causing the infection.
Before taking RIFADIN, tell your doctor if you have ever had liver problems or liver disease, any condition that affects your adrenal glands, porphyria (disorders that mainly cause nerve or skin problems), or diabetes.
RIFADIN may cause your urine, sweat, tears, and mucus to turn reddish. This is a harmless side effect, but it can permanently stain rigid or extended-wear contact lenses.
Pregnancy and RIFADIN
RIFADIN is an FDA Pregnancy Category C Drug, meaning research in animals indicates it can be harmful to a developing baby, but human studies are lacking.
It should only be used during pregnancy if the potential benefits outweigh the risk to the fetus. You should tell your doctor if you are pregnant or plan to become pregnant while taking this medication.
Because RIFADIN is excreted in human breast milk and animal studies have shown that the drug has the potential to cause tumors to form, you shouldn't take it if you are breastfeeding.
RIFADIN can decrease the effectiveness and reliability of hormonal contraceptives, including birth control pills, patches, rings, implants, and injections. Talk to your doctor about the most effective contraceptive to use while you are taking RIFADIN.
Interactions with this medication
You should always tell your doctor about any prescription, non-prescription, illegal, and recreational drugs; herbal remedies; and nutritional and dietary supplements you're taking, since RIFADIN may interact with a wide range of drugs, including the following types of medications:
- Antiarrhythmic medications
- Calcium-channel blockers
- Cardiac glycosides
- Hypoglycemic agents including sulfonylureas
- Narcotic painkillers
- Tricyclic antidepressants
RIFADIN also interacts with the following drugs:
- Atovaquone-Proguanil (Malarone)
- Digitoxin (Lanoxin)
- Cyclosporine (Restasis) Clofibrate
- Diazepam (Valium)
- Haloperidol (Haldol)
- Halothane (Fluothane)
- Isoniazid (Laniazid, Nydrazid, and others; in Rifamate, IsonaRif, and Rifater)
- Levothyroxine (Synthroid)
- Probenecid (Benemid and Probalan, in Proben-C and Colbenemid)
- Sulfasalazine (Azulfidine)
- Tacrolimus (Prograf, Advagraf)
- Theophylline (Theo-24)
- Zidovudine (Retrovir)
RIFADIN and Alcohol
Drinking alcohol while taking RIFADIN may increase your risk of liver damage.
RIFADIN and Other Interactions
RIFADIN may produce false-positive results in urine screening tests for opiates. It can interfere with other laboratory tests, too, including blood folate and vitamin B12 tests, and liver and gallbladder function tests.
Other related products
The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.