Department of Rheumatology, ISIC Superspeciality Hospital, Vasant Kunj, New Delhi, India.
Int J Rheum Dis. 2010 Oct;13(4):288-93. doi: 10.1111/j.1756-185X.2010.01564.x. Epub 2010 Aug 16.
Methotrexate (MTX) was originally synthesised as an anti-cancer drug. Soon it was also used in immunoinflammatory diseases, mainly in the field of rheumatology. However, the dose used in oncology is several-fold higher as compared to the dose used in systemic immunoinflammatory rheumatological diseases. This led to the use of terms 'low-dose MTX' (LD-MTX) and 'high-dose MTX' (HD-MTX) respectively for its use in immunoinflammatory rheumatological diseases as against its use in oncology. Extensive studies have demonstrated that therapeutic action, clinical indications, adverse effects and mechanisms of action of LD-MTX and HD-MTX are quite different. It is somewhat akin to low-dose aspirin versus high-dose aspirin with entirely different spectra of therapeutic action and adverse effects. It is important to understand this difference. This would help in allaying unfounded fear of adverse effects of LD-MTX that is often mistakenly considered the same as that of HD-MTX used in oncology.
甲氨蝶呤（MTX）最初是作为一种抗癌药物合成的。很快，它也被用于免疫炎症性疾病，主要是在风湿病领域。然而，与在肿瘤学中使用的剂量相比，在肿瘤学中使用的剂量要高几倍。这导致了在免疫炎症性风湿病中分别使用“低剂量 MTX”（LD-MTX）和“高剂量 MTX”（HD-MTX）来表示其用途，而不是在肿瘤学中使用。广泛的研究表明，LD-MTX 和 HD-MTX 的治疗作用、临床适应证、不良反应和作用机制有很大的不同。这有点类似于低剂量阿司匹林与高剂量阿司匹林，具有完全不同的治疗作用和不良反应谱。了解这一差异非常重要。这有助于消除对 LD-MTX 不良反应的无端恐惧，这种恐惧常常被误认为与肿瘤学中使用的 HD-MTX 相同。
