Low dose treatment with methotrexate-adverse drug reactions survey

Antineoplastic drugs caused various and frequent adverse drug reactions (ADR) in connection with their pharmacodynamics. Methotrexate (MTX) ADRs are preferably gastrointestinal disorders and hepatotoxicity (hepatic enzyme abnormalities). The aim of this study was to detect and analyse ADR induced by low-dose MTX treatment in rheumatology. We observed 94 patients, 63 with rheumatoid arthritis and 31 with psoriatic arthritis. All patients were co-medicated with nonsteroidal anti-inflammatory drugs (NSAID) as Diclofenacum, Indomethacinum, Piroxicamum and 51% with glycocorticosteroides. During the follow-up study we collected 18 case-reports with ADR for 17% of the patients. From the patients with registered ADR, 11 was treated with standard dose of 7.5 mg MTX for a week and 7 patients received from 10 to 15 mg for a week. The distribution of the cases according patients' gender was 9 females and 7 males. Prevail individuals in age groups' 41-50 and over 61 years. The most frequent adverse drug reactions were leucopenia, trombocytopenia, skin reactions and gastrointestinal disorders as vomiting, melaena, epigastrial pain, etc. The primary risk connected with long therapy of low doses MTX is hepatotoxicity that diagnose and treatment are painful and expensive. As a result of the appearance of ADR in 5 patients the therapy with MTX was not changed, in two cases MTX is stopped timely or the dosage is changed and in the rest 11 patients MTX was excluded from the therapeutic scheme.