Didanosine Atazanavir

Drugs that may affect tenofovir include atazanavir, indinavir, and lopinavir/ritonavir. Drugs that may be affected by tenofovir include abacavir, atazanavir, didanosine... 

Zidovudine Didanosine Stavudine Lamivudine Abacavir Tenofovir Emtricitabine Nevirapine Efavirenz TMC125 Saquinavir Indinavir Lopinavir Fosamprenavir Atazanavir Tipranavir Darunavir Raltegravir Elvitegravir Enluvirtide Maraviroc Vicriviroc Bevirimat... 

Atazanavir or fosamprenavir or nelfinavir or saquinavir/ ritonavir, and zidovudine or stavudine or tenofovir or abacavir or didanosine, and lamivudine or emtricitabine... 

Drugs that should not be combined due to overlapping toxi-cities include amprenavir oral solution plus ritonavir oral solution, atazanavir plus indinavir (due to enhanced hyperbilirubinemia), and any combination of didanosine, stavudine, and zalcitabine. Emtricitabine and lamivudine should not be combined because of their similar chemical structures, and antagonism can result when lamivudine is combined with zalcitabine, or stavudine is combined with zidovudine. 

APV, amprenavir ATV, atazanavir CNS, central nervous system CVD, cardiovascular disease D/C, discontinue ddC, zalcitabine ddl, didanosine DEXA, dual-energy x-ray absorptiometry d4T, stavudine EFV, efavirenz HDL, high-density lipoprotein HIV, human immunodeficiency virus HTN, hypertension IDV, indinavir LDL, low-density lipoprotein LPV/r, lopinavir+ ritonavir MRI, magnetic resonance imaging NNRTI, nonnucleoside reverse transcriptase inhibitor NRTI, nucleoside reverse transcriptase inhibitor NVP, nevirapine PI, protease inhibitor RTV, ritonavir SQV, saquinavir TDF, tenofovir disoproxil fumarate TG, triglyceride TPV/r, tipranivir + ritonavir ZDV, zidovudine. 

Drugs that may affect indinavir include didanosine, aldesleukin, anticonvulsants, atazanavir, nelfinavir, nevirapine, omeprazole, rifapentine, ritonavir, clarithromycin, azole antifungals, rifamycins, delavirdine, efavirenz, St. John s wort. 

Didanosine-buffered formulations - Give atazanavir (with food) 2 hours before or 1 hour after didanosine. 

Drugs that may affect atazanavir include the following antacids and buffered medications, clarithromycin, didanosine (buffered formulation only), efavirenz, H2-receptor antagonists, indinavir, itraconazole, ketoconazole, nevirapine, proton pump inhibitors, rifampin, ritonavir, St. John s wort, tenofovir, voriconazole. 

TC Lamivudine ABC Abacavir d4T Stavudine ddC Zalcitabine ddl Didanosine TDF Tenofovir ZDV Zidovudine, also abbreviated as AZT FTC Emtricitabine NVP Nevirapine DLV Delavirdine EFV Efavirenz RTV, r Ritonavir Pl/r Ritonavir boosted protease inhibitor SQV Saquinavir IDV Indinavir LPV Lopinavir NEV Nelfinavir APV Amprenavir ATV Atazanavir DRV Darunavir... 

Tenofovir NRTI1 300 mg qd3 Take with food. Nausea, diarrhea, vomiting, flatulence, headache, renal insufficiency Avoid concurrent atazanavir, probenecid, didanosine... 

The buffer in didanosine tablets and powder interferes with absorption of indinavir, delavirdine, atazanavir, dapsone, itraconazole, and fluoroquinolone agents therefore, administration should be separated in time. Serum levels of didanosine are increased when -administered with tenofovir or ganciclovir, and are decreased by atazanavir, delavirdine, ritonavir, tipranavir, and methadone (Table 49-4). 

Atazanavir Ritonavir Fosamprenavir, didanosine, efavirenz, etravirine, stavudine, tenofovir... 

Didanosine Tenofovir, ganciclovir Atazanavir, delavirdine, ritonavir, tipranavir... 

Fosamprenavir Abacavir, atazanavir, delavirdine, etravirine, indinavir, lopinavir, ritonavir, tipranavir, zidovudine Didanosine, efavirenz, nevirapine, saquinavir... 

A combination of tenofovir and didanosine is not recommended since tenofovir increases the AUC of didanosine. It also reduces the AUC of atazanavir. 

Alternative regimen Nevirapine Atazanavir Fosamprenavir Fosamprenavir + ritonavir Fopinavir/ ritonavir Abacavir/ lamivudine Didanosine/ lamivudine... 

DIDANOSINE (BUFFERED) PROTEASE INHIBITORS l efficacy of amprenavir, atazanavir and indinavir Absorption of these protease inhibitors may be affected by the buffered didanosine formulation, which t gastric pH Separate doses by at least 1 hour. Alternatively, consider using the enteric-coated formulation of didanosine... 

For some drugS/ absorption is limited by a compound s solubility/ with dissolution being highly dependent on gastric pH. The antiretroviral agent didanosine/ for example/ is an acid-labile compound/ originally formulated as a buffered preparation to improve its bio availability. Other medications/ such as atazanavir and certain azole antifungals (particularly... 

ABBREVIATIONS EFV, efavirenz 3TC, lamivudine AZT, zidovudine TDF, tenofovir disoproxil fumarate d4T, stavudine LPV/r, lopinavir/ritonavir coformulation FTC, emtricitabine NVP, nevirapine ddl, didanosine ATV, atazanavir fosAPV, fosamprenavir RTV, ritonavir IDV, indinavir NFV, nelfinavir SQV, saquinavir. 

Buffered didanosine decreases the AUC of indinavir, and the drugs shouid be given one hour apart. Buffered didanosine interacts simiiarly with atazanavir. Tipranavir with low-dose ritonavir modestly reduced the AUC of abacavir and zidovudine, and such combinations are not recommended in the UK. The changes in pharmacokinetics seen when giving other combinations of protease inhibitors with NRTIs do not appear to be clinically significant. Protease inhibitors do not affect the intracellular activation of NRTIs. 

Atazanam. The manufacturer of atazanavir found that buffered didanosine markedly decreased atazanavir plasma levels, with little change in didanosine levels, and they recommend that administration should be separated. " Conversely, although enteric-coated didanosine did not alter atazanavir levels, simultaneous administration with food reduced didanosine levels, and therefore administration should be separated. Note that didanosine , (p.797), is preferably taken on an empty stomach, whereas atazanavir , (p.818), should be taken with food. 

Atazanavir/ritonavir, darunavir/ritonavir and lopinavir/ritonavir modestly increased the levels of tenofovir, and there is at least one case report of nephrotoxicity with the combination of tenofovir, didanosine, and lopinavir/ritonavir. Saquinavir/ritonavir, ti-pranavir/ritonavir, and probably also fosamprenavir/ritonavir, have little effect on tenofovir levels. Tenofovir modestly decreased atazanavir levels, and this was minimised when ritonavir was also given. Tenofovir had no important effect on ritonavir-boosted darunavir, lopinavir, and tipranavir levels, and modestly increased those of ritonavir-boosted saquinavir in one of two studies. Indinavir and nelfinavir do not interact pharmacokineti-cally with tenofovir. 

Combination of 16 ARVs seven HIV protease inhibitors (amprenavir, atazanavir, indinavir, lopinavir, nelfmavir, ritonavir, and saquinavir), seven nucleoside reverse transcriptase inhibitors (abacavir, didanosine, emtricitabine, lamivudine, stavudine, zalcitabine, and zidovudine), and two nonnucleoside reverse transcriptase inhibitors (efavirenz and nevirapine)... 

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