Endocrine – Pharmacology · FCPS Part 1

Insulin

Class	Example	Main mechanism	Classic adverse effect
Insulin	Regular, glargine	↑ glucose uptake	⭐ Hypoglycemia
Biguanide	Metformin	↓ hepatic gluconeogenesis	GI effects, B12 ↓
Sulfonylurea	Glipizide	↑ insulin secretion	⭐ Hypoglycemia + weight gain
Meglitinide	Repaglinide	↑ insulin secretion	Hypoglycemia
TZD	Pioglitazone	↑ insulin sensitivity	⭐ Edema + weight gain
α-glucosidase inhibitor	Acarbose	↓ carb absorption	⭐ Flatulence
DPP-4 inhibitor	Sitagliptin	↑ incretin action	Generally well tolerated
GLP-1 agonist	Semaglutide	↑ insulin, ↓ glucagon, ↑ satiety	⭐ Nausea
SGLT2 inhibitor	Empagliflozin	↑ urinary glucose excretion	⭐ Genital infections

	Methimazole	PTU
TPO inhibition	✅	✅
↓ T₄ → T₃	❌	⭐ ✅
Hepatotoxicity	Less prominent	⭐⭐⭐ Important
Agranulocytosis	Possible	Possible
First-line generally	⭐ Yes	No
Pregnancy	Avoid in 1st trimester when possible	⭐ Preferred in 1st trimester