Pediatric patients on stable doses of non-biologic disease modifying anti-rheumatic drugs (DMARDs) (e.g. methotrexate, sulfasalazine) without specific risk factors (e.g. obesity, diabetes mellitus, renal disease, alcohol use, concomitant use of hepatotoxic or myelosuppressive medications) are at a low overall risk of toxicity. More frequent blood draws pose an unnecessary burden to pediatric patients and the health-care system. Patients new to treatment, on escalating doses, or with abnormal baseline labs typically require more frequent monitoring.
For more information:
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Ledingham J, Gullick N, Irving K, et al. BSR and BHPR Standards, Guidelines and Audit Working Group. Rheumatology (Oxford). 2017 Jun 1;56(6):865-868. PMID: 28339817.
Zajc Avramovič M, Dolžan V, Toplak N, Accetto M, Lusa L, Avčin T. Relationship Between Polymorphisms in Methotrexate Pathway Genes and Outcome of Methotrexate Treatment in a Cohort of 119 Patients with Juvenile Idiopathic Arthritis. J Rheumatol. 2017 Aug;44(8):1216-1223. PMID: 28572465.