Which symptom should be reported as an adverse effect of metformin?

Somnolence is considered an unusual or concerning symptom in relation to metformin use and should be reported. Metformin, commonly used for managing type 2 diabetes, typically causes gastrointestinal side effects such as nausea and diarrhea, which many patients experience as part of their initial adjustment to the medication. These symptoms can often diminish over time as the body acclimates to the drug.

Fatigue, while it can occur, is not a direct adverse effect associated specifically with metformin; it may be related to underlying diabetes or other factors, making it less indicative of a direct problem caused by the medication itself.

Somnolence is not a common or expected side effect and may warrant further assessment because it could indicate other underlying issues or interactions with the medication. Therefore, if a patient experiences this symptom while taking metformin, it is important to report it to a healthcare provider for evaluation, as it may require intervention or adjustment in treatment.