Question 1

Can GLP-1 cause thyroid cancer?

Accepted Answer

The boxed warning is based on rodent studies showing medullary thyroid carcinoma (MTC) in mice and rats. No human cases have been attributed to GLP-1 use despite 10+ years post-approval surveillance.

Question 2

Do GLP-1 medications affect mood or depression?

Accepted Answer

Mixed evidence. The FDA label has a precaution but no boxed warning. Some patients report improved mood (likely from weight loss + glycemic control); a smaller subset reports increased anxiety or low mood, especially in early weeks. Pre-existing depression history is a flag for closer monitoring.

Question 3

How do you store GLP-1 pens?

Accepted Answer

Refrigerate unopened pens at 36-46°F (2-8°C) until first use. Once started, room temperature ≤86°F (30°C) is fine for up to 28 days. Never freeze; never store in direct sunlight; do not store in checked luggage.

Question 4

How do you inject a GLP-1 safely?

Accepted Answer

Rotate sites between abdomen (≥2 inches from navel), front of thigh, and back of upper arm. Inject at room temperature (cold pens sting). Pinch a fold of skin, insert at 90°, hold 6 seconds after the click, withdraw straight. Dispose in a sharps container.

Question 5

How does Wegovy compare to Saxenda?

Accepted Answer

Both are GLP-1 agonists from Novo Nordisk. Wegovy (semaglutide, weekly) produces ~15% mean weight loss; Saxenda (liraglutide, daily) produces ~6-8%. Wegovy is also cheaper per kg-lost, more convenient, and has cardiovascular outcome data (SELECT trial). Saxenda was first approved for adolescents (2020); Wegovy followed in 2022 — both are available for ages 12-17.

Saxenda overdose: symptoms + emergency steps

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