Antiviral drug for use in case of HIV infection.
The drug should be administered during a meal.
The dose for adults is 600 mg (6 caps.) 2 times/day. A gradual increase in dose in the initial period of treatment may help to improve tolerability.
Initial dose is at least 300 mg 2 times/day for first 3 days, then increase the dose by 100 mg 2 times/day to 600 mg 2 times/day for a period of time not exceeding 2 weeks. You should not continue treatment with ritonavir at a dose of 300 mg 2 times/day more than 3 days.
The patient should be informed about the most common adverse reactions (gastrointestinal disorders moderate and severe, paresthesia), which may decrease during treatment.
Combined scheme of treatment with two protease inhibitors HIV
Clinical experience of dual therapy, that involves the use of therapeutic doses of ritonavir in combination with another protease inhibitor, is limited. When planning dual therapy with ritonavir you should take into account the pharmacokinetic interaction and safety data of drugs. You should think about the application of a combination of two protease inhibitors with the least cross-resistance.
Surveillance of acute overdose in humans is limited.
Symptoms:the patient who took 1500 mg/day of ritonavir for two days, has paresthesia, stopped by dose reduction. Another case reported the development of renal failure, accompanied by eosinophilia.
Treatment consists in carrying out supportive measures, including monitoring of vital signs and patient’s condition. It is recommended to perform gastric lavage through a nasogastric tube and take activated charcoal. There is no specific antidote. Since ritonavir is extensively metabolized by the liver and is largely associated with blood plasma proteins, dialysis will be ineffective for the removal of large quantity of the drug.
- Most commonly adult patients have asthenia, gastrointestinal (nausea, diarrhea, vomiting, lack of appetite, abdominal pain, taste disturbance) and neurological disorders including perioral and peripheral paresthesias.
- Adverse events were observed to more than 2% of patients in clinical trials phase II and phase III, which connection with the appointment of ritonavir is possible or not installed:
- CNS and peripheral nervous system: anxiety, insomnia, dizziness, headache, hyperesthesia, paresthesia, drowsiness.
- The respiratory system: increased cough, pharyngitis.
- From the digestive system: dry mouth, dyspepsia, eructation, flatulence, ulceration of the mouth.
- From the side of musculoskeletal system: myalgia.
- From the metabolic system: hyperlipidemia, weight loss.
- Dermatological reactions: macula-papular rash, itching, skin rash, sweating.
- Other: fever, pain, asthenia.
- severe degree of renal failure;
- the simultaneous use of alfuzosin, amiodarone, astemizole, bepridil, cisapride, dihydroergotamine, ergometrine, methylergometrine, ergotamine, encainide, flecainide, clozapine, pimozide, propafenon, quinidine, terfenadine, midazolam, triazolam, voriconazole, simvastatin, lovastatin, rifabutin, pethidine, piroxicam, dextropropoxyphene, fusidic acid, dipotassium clorazepate, estazolam, diazepam, flurazepam, bupropion, drugs of Hypericum perforatum;
- children up to age 3 years;
- hypersensitivity to ritonavir and/or components of the drug.
The drug should be used with caution by patients with hepatic impairment average degree, hepatitis, and other related diseases of the liver, in case of increasing of liver enzymes.
The simultaneous use of ritonavir with certain antihistamines, sedatives, hypnotics, anti-arrhythmic drugs can lead to potentially severe and/or life-threatening side effects due to possible effects of ritonavir on the metabolism of drugs in the liver.