Ritonavir is available with a prescription under the brand name Norvir. Other brand or generic formulations may also be available.[1] Ritonavir is used in combination with several other antiretroviral drugs, usually another protease inhibitor (which ritonavir boosts) and also nukes (nucleoside analogues). Sometimes drugs from other classes such as non-nukes (non-nucleoside reverse trans-criptase inhibitors) are also used.[2] Ritonavir is minimally affected by other CYP3A inhibitors, including ketoconazole. Rifampicin (rifampin), a potent CYP3A inducer, decreased the AUC of ritonavir by only 35%.[3] [1] http://health.yahoo.com/hiv-medications/ritonavir/healthwise--d03984a1.html [2] http://www.catie.ca/facts.nsf/d3d652aa551a843685256f0900686f9f/8cc975c250db9b5b852566b90005748d!opendocument [3] http://www.ingentaconnect.com/content/adis/cpk/1998/00000035/00000004/art00002?crawler=true Ritonavir is a large, lipophilic molecule that is practically insoluble in aqueous media and exhibits an exceedingly slow intrinsic dissolution rate. Although it has favorable lipophilicity, in vitro permeability studies have shown that ritonavir is a substrate of P-glycoprotein.[4] Ritonavir is a potent ( K i CYP3A4 inhibitor ( 13, 21 ). It appears to be a less potent inhibitor of CYP2B6 (50% inhibitory concentration, 2 ?M) ( 25 ).[5] Ritonavir is an anti-HIV protease inhibitor. At its full dose, it is associated with unpleasant side-effects, most notably nausea, vomiting and diarrhoea.[6] [4] http://www.biomedexperts.com/abstract.bme/14762895/ritonavir-peg_8000_amorphous_solid_dispersions_in_vitro_and_in_vivo_evaluations [5] http://journal.shouxi.net/html/qikan/lcyx/kjsjjhxffyxqk/20085525/wzjh/20080922110837631_428171.html [6] http://www.universaldrugstore.com/news/hivaids/50mg-of-ritonavir-may-be-an-effective-booster-for-some-protease-inhibitors/ Ritonavir is a reversible effector of proteasome activity that protected the subunits MB-1 (X) and/or LMP7 from covalent active site modification with the vinyl sulfone inhibitor(125)I-NLVS, suggesting that they are the prime targets for competitive inhibition by Ritonavir. At low concentrations of Ritonavir (5 microM) cells were more sensitive to canavanine but proliferated normally whereas at higher concentrations (50 microM) protein degradation was affected, and the cell cycle was arrested in the G(1)/S phase.[7] Ritonavir is used to increase the level of lopinavir in the blood, helping to make it more effective. Lopinavir and ritonavir is approved to be used along with other HIV medications.[8] Ritonavir is a potent inhibitor of CYP3A4 which is involved in the metabolism of fluticasone. Concurrent therapy might increase systemic bioavailability of fluticasone.[9] [7] http://lib.bioinfo.pl/meid:279316 [8] http://std.emedtv.com/lopinavir-and-ritonavir/lopinavir-and-ritonavir.html [9] http://www.mims.com/page.aspx?menuid=alertr&druglist=veramyst+spray%3creg%3e**ritonavir** Ritonavir is known to induce nausea in significant number of AIDS patients [7 ,8 ,12 ,14 ] but has not been studied in an animal model. In this study, we observed that SbE attenuated kaolin intake or pica in ritonavir-treated rats.[10] Ritonavir is not a cure for HIV infection. Patients may still get illnesses and infections associated with HIV.[11] Ritonavir is a 721 Da, short half-life (several hours]), hepatically eliminated, orally active HIV protease inhibitor used to treat HIV infection since 1996. In addition to inhibiting the HIV protease, ritonavir is a potent inhibitor of human liver P450-3A4 activity and has been shown to block the conversion of inactive, 45 kDa pro-caspase-1 to active, 20 kDa subunits that dimerize to form catalytically active caspase-1 [15 , 16 , 17 ].[12] [10] http://www.aidsrestherapy.com/content/2/1/12 [11] http://www.drugs.com/cdi/ritonavir.html [12] http://www.joplink.net/prev/200805/08.html Ritonavir is rarely used as a protease inhibitor any more. It is difficult for patients to tolerate.[13] Ritonavir is just a protease inhibitor like any other. What you heard may have to do with the fact that it also happens to be a very potent inhibitor of the metabolism of many other drugs, including other protease inhibitors.[14] Ritonavir is an FDA approved drug for HIV treatment, being used well over a decade with tolerable side effects [30 ]. [15] [13] http://www.aidsinfonet.org/fact_sheets/view/442 [14] http://www.hopkins-hivguide.org/q_a/patient/basic_science/nartis_vs._nnrtis_vs._ritonavir.html?contentinstanceid=251470&siteid=7151 [15] http://www.molecular-cancer.com/content/8/1/26 Ritonavir is now approved with other anti-HIV drugs in the treatment of HIV-1 infection in children in individuals over 1 month in age. Studies have shown that ritonavir works as a booster for some other PIs.[16] Ritonavir is a peptidomimetic agent that inhibits both HIV-1 and HIV-2 proteases, thereby preventing the cleavage of Gag-Pol polyproteins and resulting in the production of noninfectious viral particles. This agent is more active against HIV-1.[17] [16] http://www.news-medical.net/?tag=/ritonavir [17] http://www.fpnotebook.com/hiv/pharm/rtnvr.htm Protease is the enzyme that forms the new structural proteins and enzymes. Ritonavir blocks the activity of protease and results in the formation of defective viruses that are unable to infect the body's cells.[21] [21] http://www.medicinenet.com/ritonavir/article.htm Lopinavir/ritonavir blocks the ability of HIV to make copies of itself and may help other anticancer drugs work better or may block the growth of cancer cells. Ritonavir blocks the breakdown of lopinavir.[30] Lopinavir/Ritonavir may improve immune system function. This may reveal hidden infections in some patients.[31] Lopinavir and ritonavir combination will not cure or prevent HIV infection or AIDS; however, it helps keep HIV from reproducing and appears to slow down the destruction of the immune system. This may help delay the development of problems usually related to AIDS or HIV disease.[32] [30] http://www.cancer.gov/dictionary/?cdrid=642978 [31] http://www.drugs.com/cdi/lopinavir-ritonavir.html [32] http://www.mayoclinic.com/health/drug-information/dr600431 Patients taking other medications must consult with their physicians before starting ritonavir. Abbott has prepared physician and patient instructions regarding potential drug interactions.[45] Patients are instructed to take ritonavir at the same time as its accompanying protease inhibitor. However, ritonavir is unpopular with many patients because of its large size and because of the recommended need for refrigeration.[46] Patients received enfuvirtide (90 mg twice daily [bid], subcutaneous injection) for 7 days and either ritonavir (200 mg bid, ritonavir study, orally) or saquinavir/ritonavir (1000/100 mg bid, saquinavir/ritonavir study, orally) for 4 days on days 4 to 7. Serial blood samples were collected up to 24 hours after the morning dose of enfuvirtide on days 3 and 7.[47] [45] http://www.aids.org/atn/a-243-02.html [46] http://clinicaltrials.gov/ct2/show/nct00432783 [47] http://www.cababstractsplus.org/abstracts/abstract.aspx?acno=20043138259 Ritonavir is used to treat human immunodeficiency virus (HIV) infection. It belongs to a class of drugs called protease (pro' tee ace) inhibitors, which slow the spread of HIV infection in the body.[1] Ritonavir administered once daily with elvitegravir exhibited nonlinear pharmacokinetics, with a 119-fold increase in the area under the plasma concentration–time curve over the dosing interval over a 20- to 200-mg dose range. [2] Ritonavir is a protease inhibitor used for treating HIV and fluticasone is an inhaled corticosteroid used for treating asthma. Symptoms of Cushing's syndrome developed in one patient alter taking both drugs for 5 months.[3] [1] http://www.consumerreports.org/health/prescription-drugs/ritonavir/how-is-it-used.htm [2] http://www.nature.com/clpt/journal/v85/n1/full/clpt2008168a.html [3] http://www.accessmylibrary.com/premium/0286/0286-27309048.html Ritonavir reduced intersubject variability in the saquinavir AUC from 60% to 28%. [4] Ritonavir is just one of many powerful new medicines for treating people with HIV, many of whom belong to communities in which the use of illegal drugs is endemic. There is also evidence that drug users are deliberately mixing prescription medicines with drugs like LSD and MDMA to modify or enhance their effects.[5] Ritonavir (1200 mg/d) and stavudine were added to lamivudine in 1996, when the CD4 cell count was 3 cells/?L and the HIV level was 433 000 RNA copies/mL. [6] [4] http://www.nature.com/clpt/journal/v63/n4/abs/clpt199837a.html [5] http://www.newscientist.com/article/mg15520903.300-deadly-combination.html [6] http://www.annals.org/cgi/content/full/129/8/670-a Ritonavir may have enhanced rifabutin bioavailability by reducing either intestinal or hepatic metabolism or both. Clarithromycin is an alternative to rifabutin for antimycobacterial therapy that may be administered concurrently with ritonavir.[7] [7] http://www.nature.com/clpt/journal/v63/n4/abs/clpt199832a.html Aptivus, a sulfa-containing drug, should be used with caution in patients with a known sulfa allergy. Mild to moderate rashes including urticarial rash, maculopapular rash, and possible photosensitivity have been reported in subjects receiving Aptivus/r.[1] Aptivus, a non-peptidic protease inhibitor, co-administered with low-dose ritonavir is indicated for combination antiretroviral treatment of HIV-1 infection in highly pre-treated adult patients with virus resistant to multiple protease inhibitors (PIs). This authorization was based on exceptional circumstances given that HIV/AIDS is a life threatening illness with a need for rapid access to new treatment options.[2] [1] http://i-newswire.com/pr27344.html [2] http://www.biotech-intelligence.com/html/html/46281e468f3b11af5bd5baf12b91809e.html OBJECTIVE: The Antiretroviral Pregnancy Registry was established in 1989 to collect data on birth defects after pregnancy exposures to antiretroviral therapy. Using Registry data, this study estimates the birth defect risk after pregnancy exposures to lopinavir/ritonavir.[32] OBJECTIVE: Characterization of resistance development in virologic failure patients on the protease inhibitor darunavir administered with low-dose ritonavir (DRV/r) in the 48-week analysis of TMC114/r In Treatment-experienced pAtients Naive to lopinavir (TITAN). DESIGN: TITAN is a randomized, controlled, open-label, phase III, noninferiority trial comparing the efficacy and safety of DRV/r with that of lopinavir/ritonavir (LPV/r) in HIV-1-infected, treatment-experienced, LPV-naive patients.[33] OBJECTIVE: Combination antiretroviral therapy with lopinavir/ ritonavir (LPV/r) has been highly effective in clinical trials. Results of long-term therapy with LPV/r-based regimens have not been previously reported.[34] [32] http://www.find-health-articles.com/rec_pub_19381099-lopinavir-ritonavir-pregnancy.htm [33] http://www.druglib.com/druginfo/norvir/ [34] http://www.proteases.org/showabstract.php?pmid=17630547 Kaletra interacts with a wide variety of other medications. Be careful to avoid combining it with any of the drugs listed under "Most important fact about Lopinavir, Ritonavir.".Also be especially careful when taking Viagra.[18] Kaletra is indicated, in conjunction with other antiretrovirals, for the treatment of HIV infection. [19] Kaletra is an HIV medication from the class of HIV drugs known as protease inhibitors. Protease Inhibitors stop HIV replication by preventing the enzyme protease from cutting the virus into the shorter pieces that it needs to make copies of itself.[20] [18] http://www.drugs.com/pdr/lopinavir-ritonavir.html [19] http://www.thefreelibrary.com/lopinavir%2fritonavir+(kaletra)-a068951366 [20] http://aids.about.com/od/hivaidsletterk/g/kaletra_def.htm This HIV treatment information is for educational purposes only and is not intended to replace the advice of your doctor or health care provider. We encourage you to discuss with your doctor any questions or concerns you may have. For successful case studies, using a simple and natural home HIV cure: http://cureaidsinfo.com