The package insert of the medicine Ribavirin

the package insert of the medicine Ribavirin. Sale under medical prescription.

what For?

This product is indicated for all forms of viral hepatitis.

Pharmacokinetics

How it works?

Soon after oral administration, plasma concentrations increase rapidly, reaching a peak between 1 and 1.5 hours. The bioavailability of the oral solution or capsule is from 20% to 50%. A large amount of the ribavirin dose administered orally is retained in the red blood cells and tissues, which are responsible for its long half-life in plasma. It is rapidly phosphorylated so that intracellular mono-, di-, and triphosphate, which are likely to be essential for antiviral activity. The metabolic pathway secondary probably includes the hydrolysis to acid tricarboxílico,-ribosilação and decomposition of the ring of triazole . Ribavirin and its metabolites are eliminated slowly through the kidneys, and the renal excretion accounts for approximately 40% of total elimination from the body. The half-life of elimination of ribavirin varies from 24 to 35,5 hours, in adult patients. Ribavirin is not completely removed by hemodialysis, necessitating the need to make dosage of ribavirin before adjusting the dose.

Contraindications

When should I not use?

in Addition to pregnancy and lactation, this product is contraindicated to patients with known hypersensitivity to ribavirin or to other components of the formula.

do NOT TAKE MEDICINE IN THE KNOWLEDGE OF YOUR DOCTOR. It CAN BE DANGEROUS TO YOUR HEALTH

Dosage

How to use?

– Hepatitis A and B : Ribavirin 10 mg/kg/day, orally, divided into 4 doses (for 14 days) has been shown to be beneficial when administered to children with Hepatitis type A or B. has Not made the distinction between HbsAg positive or negative. A significant reduction in values of SGPT have occurred in the 71 day of treatment when compared with patients treated with placebo. The serum bilirubin decreased on all days in patients treated with ribavirin. It was also observed improvement in symptoms (improvement of appetite, nausea, vomiting, feeling of well-being). Two hundred milligrams of ribavirin, orally, 3 times a day for two weeks administered to patients with Hepatitis A showed a significant improvement in the total bilirubin and direct, SGPT and SGOT and better weight gain than patients treated with placebo.

Side Effects

What are the evils that can cause me?

Effects Haematology: there were No observed abnormalities in blood cell counts in patients who received 1000 mg of ribavirin orally daily; although they have been recorded reductions in hemoglobin with oral doses higher, it was not observed any effect in the bone marrow. The oral administration of ribavirin at doses up to 1 g/day for more than 1 week resulted in a reduction in the transient in the value of the hematocrit in the order of 20%.

Cardiovascular: Congestive Heart Failure: Were reported the following adverse effects in infants severely sick at the risk of life: CARDIAC arrest, HYPOTENSION, BRADYCARDIA, TOXICITY DIGITÁLICA AND BIGEMINISMO. The role of ribavirin in this set is not known. Heart failure has been observed, resulting in death in 8 of 10 infants with heart function compromised. It was not determined whether ribavirin has contributed to the decrease of cardiac function or if this was caused by other factors.

Effects on the Central Nervous System: SEIZURES and WEAKNESS were associated with ribavirin intravenous trial.

Effects Gastrointestinal : there were gastrointestinal symptoms during treatment with ribavirin; however, these symptoms have not been reported in other studies.

Effects Urogenital: In mice, the administration of ribavirin resulted in atrophy of the tubules, seminiferous, reduction of sperm concentrations and high numbers of sperm with morphologically abnormal.

Hepatotoxicity: Elevations in serum bilirubin was the main adverse effect during treatment with ribavirin oral. The elevations of the level of bilirubin usually were in the range of 1.6 to 2.2 mg %, and the increases were mainly the type of indirection. There were no significant increases in liver enzymes.

Overdose

what to do if someone use a larger amount than is recommended?

When the biosintética ribavirin (ribavirin) is administered for a prolonged period and in high doses, may result in reduced mild and reversible hemoglobin, hematocrit, and in the count of red blood cells. these reductions are reversible. if they exceed the minimum limits, the administration of the drug should be discontinued. these are the first signs of toxicity and superdose. it is necessary to make the monitoring haematology of patients submitted to prolonged treatments with ribavirin.