Lamivudine Trimethoprim

Drugs that may interact with lamivudine include zalcitabine and trimethoprim/sulfamethoxazole. 

The most common adverse effects of lamivudine seen at doses used to treat HBV are mild they include headache, malaise, fatigue, fever, insomnia, diarrhea, and upper respiratory infections. Elevated alanine aminotransferase (ALT), serum lipase, and creatine kinase may also occur. The safety and efficacy of lamivudine in patients with decompensated liver disease have not been established. Dosage adjustment is required in individuals with renal impairment. Coadministration of trimethoprim-sulfamethoxazole decreases the renal clearance of lamivudine. 

Lamivudine is associated with an increased risk of pancreatitis in children and should be used with great caution in children who have had pancreatitis or are at high risk for it. Dosage adjustment is necessary in patients with renal impairment. Lamivudine should not be used in combination with zalcitabine, because they inhibit each other s activation by phosphorylation. Trimethoprim inhibits the renal elimination of lamivudine. 

Potential adverse effects are headache, dizziness, insomnia, fatigue, and gastrointestinal discomfort, although these are typically mild. Lamivudine s bioavailability increases when it is -administered with trimethoprim-sulfamethoxazole. Lamivudine and zalcitabine may inhibit the intracellular phosphorylation of one another therefore, their concurrent use should be avoided if possible. Short-term safety of lamivudine has been demonstrated for both mother and infant. 

Use of trimethoprim in high doses should be avoided when coadministering lamivudine. Coadministration of stavudine with drugs causing peripheral... 

Lamivudine (3TC) Epivir 150 mg and 300 mg tablets 10 mg/ml solution Trimethoprim/sulfamethoxazole, posaconazole... 

OCT Lamivudine Procainamide Meformin Trimethoprim Cimetidine Cimetidine f plasma exposure of lamivudine f procainamide toxicity f plasma exposure of metformin... 

Nakatani-Freshwater, T., Babayeva, M., Dontabhaktuni, A., Taft, D. R. (2006). Effects of trimethoprim on the clearance of apricita-bine, a deoxycytidine analog reverse transcriptase inhibitor, and Lamivudine in the isolated perfused rat kidney. The Journal of Pharmacology and Experimental Therapeutics, 319, 941—947. 

Emtricitabine is not metabolized to a significant extent by CYPs, and it is not susceptible to any known metabolic drug interactions. The possibility of a pharmacokinetic interaction involving renal tubular secretion, such as that between trimethoprim and lamivudine, has not been investigated for emtricitabine, although the drug does not alter the pharmacokinetics of tenofovir. 

Following oral administration, lamivudine is absorbed rapidly with a bioavailability of about 80% in adults. Peak plasma levels average approximately 1000 ng/mL after 100-mg doses. Lamivudine is distributed widely in a volume comparable with total-body water. The plasma t,/2 of elimination averages about 9 hours, and approximately 70% of the dose is excreted unchanged in the urine. About 1% is metabolized to an inactive trawY-sulfoxide metabolite. In HBV-infected children, doses of 3 mg/kg per day provide plasma exposure and trough plasma levels comparable with those in adults receiving 100 mg daily. Dose reductions are indicated for moderate renal insufficiency (creatinine clearance <50 ml/min). Trimethoprim decreases the renal clearance of lamivudine. 

Items 92-93. A 30-year-old hospitalized AIDS patient has a CD4 cell count of 50/ tL. He is being treated with a highly active antiretroviral therapy (HAART) regimen consisting of zidovudine (ZDV), lamivudine (3TC), and indinavir. Other drugs being administered to this patient include acyclovir, clarithromycin, foscamet, rifabutin, and trimethoprim-sulfamethoxazole. 

In a study of 14 HIV-positive patients taking co-trimoxazole 960 mg daily for 5 days, it was found that the AUC of a single 300-mg dose of lamivudine given on day 4 was increased by 43% and the renal clearance was decreased by 35%. The pharmacokinetics of the trimethoprim and the sulfamethoxazole were unaffected. Similarly, in a population pharmacokinetic analysis, the concurrent use of lamivudine and co-trimoxazole was associated with a 31% reduction in the apparent oral clearance of lamivudine, and an estimated 43% increase in steady-state lamivudine levels. The UK manufacturer notes that the interaction is due to trimethoprim, and that sulfamethoxazole did not interact. ... 

Simultaneous didanosine, folic acid, ganciclovir, lamivudine, nevirapine, pyrazinamide, ranitidine, rifampin, stavudine, sulfamethoxazole, trimethoprim, zidovudine Noninterfering adefovir, amprenavir, delavirdine, efavirenz, fluconazole, indinavir, itraconazole, methadone, nelfinavir, oxazepam, pyrimethamine, rifampin, ritonavir, saquinavir, zalcitabine... 

Noninterfering acetaminophen, amineptine, amphotericin B, aspirin, bromazepam, buspirone, citalopram, clobazam, diazepam, didanosine, fluconazole, flunitrazepam, flu-voxamine, hydroxyitraconazole, isoniazid, itraconazole, lamivudine, loprazolam, lora-zepam, metronidazole, minalcipram, nordiazepam, omeprazole, paroxetine, pyrimethamine, rifampin, sertraline, stavudine, sulfadiazine, trimethoprim, venlafaxine, zal-citabine, zidovudine, zolpidem, zopiclone... 

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