Psoriasis is a type of epidermal, hereditary, immune-mediated inflammatory disorder that is often connected to metabolic comorbidities especially in the elderly. Methotrexate is administered once weekly in moderate or severe psoriasis, in addition to anti-glucose effects, Metformin has anti-inflammatory and metabolic effects that can be beneficial in improving the results of treating psoriasis. The purpose of this study was to assess the efficacy, effectiveness and safety of methotrexate treatment with or without the use of adjunctive metformin in the elderly patients who have psoriasis, hypertension and metabolic comorbidities. A non-randomized controlled trial was conducted of 60 elderly patients who had psoriasis, diabetes mellitus and hypertension, either or both. Patients were classified into two groups: Group I was given methotrexate and metformin, and Group II was given methotrexate. The Psoriasis Area and Severity Index (PASI) was used as a measure of clinical effectiveness after three months. The monitored parameters were biochemical, hematological, and metabolic parameters to assess systemic safety. Both Group I (methotrexate + metformin) and Group II (methotrexate alone) showed significant reductions in PASI scores over three months; however, Group I achieved a markedly greater mean PASI reduction compared with Group II. Group I also showed considerable changes in body weight, BMI, fasting glucose, and triglyceride levels, more stable hepatic, renal, and hematological parameters, and a reduced number of adverse effects compared to Group II. Adjunctive metformin enhances the effectiveness and safety of methotrexate therapy in elderly psoriatic patients with metabolic comorbidities.