Report: Metformin Potential in Predisposing Arthralgia, Type II Cross Reactivity Secondary to Group A Streptococcus Infection and Other Comorbidities in Treating PCOS

The document reported on a case of a female with Polycystic Ovarian Syndrome (PCOS) treated with metformin for over two years, who subsequently developed hyperuricemia, migraine, neurological pain, severe joint and knee pains, and rheumatic fever. Treatment with benzathine benzyl penicillin for rheumatic fever led to a Type IV delayed hypersensitivity reaction. The report highlighted the potential adverse effects of metformin, including back pain, swollen joints, and rare behavioral alterations, and discussed the risks of allergic reactions to penicillin, which affects 10% of patients.