###Human: After switching to insulin injection, my dad gets stomach pain and swollen feet. Why? ###Assistant: Hi. From your history, it seems your father is suffering from uncontrolled Diabetes mellitus for seven months or more which was not controlled with Metformin. The present complaints you have mentioned after starting insulin, may not be actually related to insulin rather may be due to uncontrolled diabetes or else a systemic disease most probably involving liver in view of jaundice. Or even a renal problem can cause the same because he is on pain killers (Ibuprofen) which may effects negatively to kidneys in such patients. First, stop Ibuprofen at the earliest. Make sure insulin is injected at proper site, rule out insulin site infections. Rule out kidney and liver involvement by doing RFT (renal function test) and LFT (liver function test) along with blood routine. Why insulin was directly started after Metformin is also a doubt? There are many good oral tablets which are stronger than Metformin that may be tried before insulin if no contraindications. Weight loss may be due to uncontrolled sugars which are signified by blood sugars postmeal. Liver function test. Renal function test. Complete blood count with ESR (erythrocyte sedimentation rate). HBA1c (glycated hemoglobin). Proper diabetic diet. Regular aerobic exercises for 30 minutes per day. Insulin maybe continued-special care on storage, site of injection, methods of injecting. May be shifted to anti-diabetic tablets once the patient is stable.