Primidone Ritonavir

X effects W/ carbamazepine, nelfmavir, phenobarbital, phenytoin, primidone, rifampin, ritonavir EMS Use CNS depressants w/ caution concurrent EtOH use can T resp depression, may T QT interval, monitor ECG OD May cause miosis, CNS and resp depression, hypotension, bradycardia, and CV collapse activated charcoal may be effective for PO form naloxone can be used give slowly and only give enough to reverse resp depression... 

Clinically important, potentially hazardous interactions with amprenavir, aprepitant, atazanavir, carbamazepine, chlorpheniramine, cimetidine, clarithromycin, clorazepate, CNS depressants, darunavir, delavirdine, dexamethasone, efavirenz, erythromycin, esomeprazole, fluconazole, fluoxetine, fosamprenavir, grapefruit juice, griseofulvin, imatinib, indinavir, itraconazole, ivermectin, ketoconazole, lopinavir, nelfinavir, nevirapine, phenobarbital, phenytoin, primidone, rifabutin, rifampin, ritonavir, roxithromycin, saquinavir, St John s wort, telithromycin, tipranavir... 

Levonorgestrel is metabolised in the liver and drugs, including primidone, phenytoin, carbamazepine, St John s wort, griseofulvin, rifampicin, rifabutin and ritonavir, that induce liver enzymes will increase its metabolism and may... 

It is likely that phenobarbital and other barbiturates will increase the metabolism of the protease inhibitors, thereby reducing their levels and possibly resulting in failure of the antiretrovirals. However, one case su ested that this may not have occurred with primidone and ritonavir/saquinavir, although this should be viewed with caution. 

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