Page 259 - Pharmacology Mnemonics and Short Notes

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Mechanism

 Inhibit thyroid hormone synthesis

o Block peroxide that catalyse iodination of thyroglobin

o Block coupling of thyroglobin

o Block coupling of MIT and DIT (mono iodo thyroxine and di

iodo thyroxine)

o Inhibit peripheral conversion of T 4  T 3

 Methemazole  preferred because can be administered per day

 PTU (propylthiouracil) P  preferred in pregnancy + do not cross
placenta + do not come in milk

Toxicity (reversible)

Rash + vaculitis + agranulocytopenia + liver dysfunction

Anion inhibitors

Thiocyanates and perchlorates

 Block uptake of iodide

Adverse effect  aplastic anemia

Radioactive iodine

Taken up by gland

Dose  is large enough to cause destruction of Gland

 Permanent treatment without surgery

Beta Blockers

Control tachycardia and other cardiac abnormalities produced by
thyrotoxicosis

Contents  Also inhibit peripheral conversion of T 4 into T 3

Pharmacology Mnemonics and Short Notes By Muhammad Ramzan Ul Rehman