Tirzepatide 2.5 mg is the starter weekly dose used to begin therapy, not a therapeutic maintenance dose. It’s initiated for adults with type 2 diabetes to improve blood sugar alongside diet and exercise, and for chronic weight management or obesity-related obstructive sleep apnea under the respective brands after titration. After 4 weeks at 2.5 mg, the dose is typically increased to 5 mg, with further 2.5 mg step-ups as needed. It should not be used for type 1 diabetes or in people with certain thyroid tumor histories. Common GI side effects can occur, and medical supervision is required.