Azathioprine Trimethoprim

ACE-I, angiotensin-converting enzyme inhibitors ARB, angiotensin-receptor blockers AZA, azathioprine CMV, cytomegalovirus CPK, creatinine phos-phokinase CSA, cyclosporine HMG-CoA, 3-hydroxy 3-methylglutaryl coenzyme A reductase K+, potassium LFTs, liver function tests Rl, renal insufficiency SCr, serum creatinine SRL, sirolimus TAC, tacrolimus TMP-SMX, trimethoprim-sulfamethoxazole. 

Other drugs studied by Moore et al. include chlorine containing photosensitizers (178), the effect of surfactants on photosensitizers (179), photosensitization by malarial drugs (180), nalidic and oxolinic acids (181), 6-mercaptopurine (182), azathioprine and nitroimidazole (183), 7-methylbenz[c]acridine and related products (184), naproxen, ben-oxaprofen and indomethacin (185), mefloquine (186), sulfamethoxazole and trimethoprim (187), benzydamine (188), photodecomposition of hydrochlorthiazide (189), tetracycline (190), frusemide (191), 6-mercaptopurine (192), 7-methylbenz[c]acridine (193), metronidazole, misonidazole and azathioprine (194), misonidazole and metronidazole (195), benzydamine (196), components in drug formulations (197) and sulfamethoxazole (198,199). 

Noninterfering amikacin, amphotericin B, azathioprine, carhenicillin, chloral hydrate, ci-metidine, dopamine, fluphenazine, ftirosemide, hydrochlorothiazide, insulin, levothyrox-ine, methylprednisolone, nitroglycerin, oxacillin, prednisone, procainamide, sulfamethoxazole, tolazamide, tolbutamide, triamterene, trimethoprim... 

Information appears to be limited and the interaction is not established. Although there is some evidence of increased risk of haematological toxicity in renal transplant patients taking azathioprine if they are treated with co-trimoxazole or trimethoprim this has not been shown in all studies. Two of the early studies suggested that the incidence of leucopenia with co-trimoxazole was related to the time after transplantation, and it improved if the dose of azathioprine was decreased or temporarily suspended. Prophylaxis with co-trimoxazole post-transplant is commonly used in some centres. 

There is some evidence that the risk of haematological toxicity may be increased in renai transpiant patients taking azathioprine if they are given co-trimoxazoie or trimethoprim, particularly if they are given for extended periods. However, other evidence suggests that the drugs may be used together safety, and the combination is commoniy used in practice. 

The observation that haematologieal toxieity often seemed to occur in renal transplant patients given azathioprine and co-trimoxazole, prompted a retrospective survey of the records of 40 patients. It was found that there was no difference in the incidence of thrombocytopenia and neutropenia in those given azathioprine, either alone, or with co-trimoxazole, (trimethoprim 160 to 320 mg and sulfamethoxazole 800 mg to 1.6 g daily) for a short time (6 to 16 days), but a significant increase occurred in the incidence and duration of thrombocytopenia and neutropenia if both drugs were given together for 22 days or more. ... 

Another report describes a marked fall in white cell counts in renal transplant recipients during concurrent treatment with either co-trimoxazole (described as frequent) or trimethoprim (3 cases). In one case the fall occurred within 5 days and was managed by temporarily withdrawing the azathioprine and reducing the trimethoprim dosage from 300 to 100 mg daily. ... 

Class 2 (High PermeabiUty, Low Solrrbility) Azathioprine, Azithromycin, Alprazolam, Warfarin, Haloperidol, Glipizide, Griseofulvinum, Danazol, Dapsone, Diclofenac, Indometacin, Itraconzol, Carbamazepine, Carvedilol, Ketoconazole, Lansoprazol, Mebendazole, Mefloqrrine, Nalidixic acid. Nevirapine, Piroxicam, Praziquantel, Ritonavir, Rifampicinirm, Spironolactone, Tamoxifen, Terfenadine, Trimethoprim, Ibnprofen, lopanoic add, Lovastatin, Naproxen, Oxaprozin, Flubiprofen, Cisapride. ... 

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