Methotrexate (Methotrexate). Low doses of methotrexate, 15 mg weekly, have a corticosteroid effect in some asthmatics, but side effects are relatively common and include nausea (decreases with methotrexate as a weekly injection), abnormal blood change, and liver damage. Careful monitoring is required (monthly blood count and liver enzyme tests). Gold preparations. Gold preparations have long been used in the treatment of chronic arthritis. Controlled trials of gold oral preparations (auranofin) have shown a corticosteroid effect in chronic asthmatics taking oral corticosteroids, but side effects (skin rash and nephropathy) are limiting factors. Cyclosporin. At low doses of oral cyclosporine in patients with corticosteroid-dependent asthma, an improvement in symptom control is noted, but this does not matter in clinical practice, and its use is limited to severe side effects (nephrotoxicity, hypertension). Tumor necrosis antifactor. Anti-TNF (antibody or soluble receptor) therapy has been shown to reduce symptoms or exacerbations in patients with severe asthma, but large-scale controlled studies have not yet shown efficacy, so this treatment is not approved for asthma. Anti-TNF is ineffective in patients with COPD. Mucolytics. Some drugs reduce sputum viscosity by breaking the disulfide bonds between sputum glycoproteins, but in clinical practice these drugs have disappointed. The most common drug, N-acetylcysteine, reduces exacerbations in meta-analyzes, but in a large, placebo-controlled study of COPD, there was no overall clinical effect, although patients did not use inhaled corticosteroids and no reduction in exacerbations was detected.