Drug profile of Ritomune 100mg
Ritomune tablets are anti-retroviral medication which containing an active moiety known as Ritonavir.
Ritomune is classified as HIV protease inhibitor drug, which is peptidomimetic agent containing both HIV-1 & HIV-2 protease inhibitor activity.
Ritomune is also a CYP3A inhibitor.
Ritomune is exhibits anti-retroviral activity by interceding with reproductive cycles of HIV.
Brand name: Ritomune
Active substance: Ritonavir
Pack: 60 tablets in a container
Category: Anti-retroviral drug
Prescribing information of Ritomune 100mg
Ritomune tablets are widely used for treating HIV-1 infection by combining with other anti-retroviral medications.
Mechanism of Ritomune 100mg
HIV protease enzymes which is involves in separation of structural & multiplicative proteins that may produce from major HIV genes, like gag & pol. This activity of enzyme should be reduced due to inhibiting the protease enzyme by ritonavir, an active substance of Ritomune tablets.
Gal: conceal the proteins complicated in core & nucleocapsid.
Pol: conceal the reverse transcriptase, ribonuclease H, integrase & protease.
The separation of gal-pal polyprotein should be prevented by ritonavir which leads to production of immature and non infectious viral particles.
The maximum plasma concentration time of ritonavir after the dose administration, causes within 2 hours & 4 hours relatively in both fasted & non fasted state.
Food will decrease the bioavailability slightly.
Cmax value 0.84ng/ml plus or minus 0.39ng/ml
Cmin value: 6.6ng/ml.hr plus or minus 2.4ng/ml.hr
Volume of distribution is 20 to 40L
CSF Plasma ratio 0.52
Semen plasma ratio <0.04
Nearly 98 to 99% of drug ritonavir is binds to human plasma protein.
Isopropylthiazole oxidation is the major metabolite of ritonavir and it is similar in action of ritonavir.
CYP3A is a major isoenzymes involved in the metabolism of ritonavir.
The excretion of ritonavir should be occurs through urine & feces as an unchanged form
The terminal half life period is 3 to 5 hours
When to take the Ritomune 100mg
Ritomune tablets should be taken with meals, do not crush, chew or broke the tablets.
Ritomune should be combined with other anti-retroviral drugs.
Dosage regimens of Ritomune 100mg
The prescribed doses of Ritomune for adults are;
600mg should be administered orally as two times a day.
Ritomune tablets should be initiated by not less than 300mg as two times a day followed by increased dose at 2 to 3 days by 100mg as twice daily.
The maximum dose is 600mg and it should not be exceeded.
Ritomune should be used by combining with other antiretroviral drugs.
The prescribed dose of Ritomune is 350 to 400mg/m2 as two times a day for pediatric patients with age of older than 1 month.
The dose should not be exceeded to 600mg
The initial dose of Ritomune is 250mg/m2 two times day and increased at 2 to 3 days interal by 50mg/m2 as two times a day.
Depending on body surface area, the dose should be calculated.
Dose reduction is required when Ritomune is combined with atazanavir, darunavir, fosamprenavir, saquinavir & tipranavir.
Ritomune 100mg caused side effects
Gastro esophageal reflux disease
Elevation in urination
Drug- drug interaction
Ritomune with drugs which are metabolized by CYP3A causes increasing the plasma concentration of these agents.
Ritomune with HIV-1 protease inhibitors causes increasing effect of concentration of these drugs.
Ritomune with integrase inhibitors, causes decreasing the effect of concentration of these drugs.
Ritomune with analgesic causes increasing concentration of analgesics.
Ritomune with anti-cancer or anti-arrhythmic drugs causes increasing the effect of concentration of these drugs.
Ritomune with warfarin causes either decreasing or increasing the concentration of warfarin.
Ritomune with anti-convulsants, anti-depressants causes increasing in concentration of these drugs.
Ritomune with anti-fungal, anti-infective, anti-gout, causes increasing the concentration of these drugs.
Ritomune with cardiovascular drugs, causes increasing in concentration of CVS drugs.
Ritomune with lipid lowering drugs causes increasing the concentration of these drugs.
Food drug interaction
Ritomune tablets should be administered with food, causes diminishing the gastrointestinal side effects.
Ritomune should be contraindicated to hypersensitivity acquired patients.
Some drugs are contraindicated to ritonavir;
Alfuzosin, ranolazine, anti-arrhythmia, voriconazole, colchicines, anti-psychotics, ergot derivatives, Cisapride, st. John’s wort, lovastatin, simvastatin, sildenafil, Midazolam
Serious adverse reactions may occur due to drug interactions like
Ritomune with CYP3A inducers or inhibitors
PR interval extension
Immune reconstitution syndrome
These are all some serious effects occurred during the therapy with Ritomune, to over come the problems patients must be;
Provide with supportive measures
Counsel about the adverse effect before starting the treatment
In severe condition, stop the treatment.
Maintain the lab value
Patient should be frequently monitoring with the signs & symptoms associated to particular effects.
Pregnancy and lactation
Pregnancy category C
Ritomune should not be used in pregnancy & lactating period.
Generally HIV infected women should not undergo breast feeding, for avoiding the spreadness of disease to baby.
Storage and handling
Ritomune tablet container should be stored on below 30oC
Keep the container away from heat, moisture & light.
Patient must get advice from physician to avoid the over dosage problem, in case of missed dose.
Follow the regular dosing schedule prescribed by physician.
Providing supportive measure to the patient with over dosage of ritonavir
Monitor the manifestation associated to over dosage condition of Ritomune.
No special antidote is required for over dosage
Gastric lavage or emesis should be used in patient for eliminating the ritonavir content from the body
Activated charcoal is used to adsorbed the ritonavir content occurred in the body.
Ritonavir is intensively metabolized and largely binds to human plasma protein so hemodialysis process is not valuable for over dosage of ritonavir.