Thyrotoxic Periodic Paralysis (TPP)

Q: Out of the following, which one can be used as an adjuvant treatment in Thyrotoxic Periodic Paralysis (TPP)?

A) Calcium Channel Blockers

B) Nonselective Beta Blockers 

C) Corticosteroids

D) Intravenous magnesium

E) Intravenous Dextrose

Answer: B (Nonselective Beta Blockers -propranolol)

In Thyrotoxic Periodic Paralysis (TPP), propranolol, a nonselective beta-blocker, has been shown to prevent the intracellular shift of potassium and phosphate by blunting the hyperadrenergic stimulation of Na+/ K+–ATPase. 

Studies have shown, propranolol given alone (orally or iv) normalizes serum potassium levels for an average of 2 hours. Nonselective Beta Blocker can be a good adjuvant treatment in TPP permissive blood pressure.

#endo

References:

1. Shayne P, Hart A. Thyrotoxic periodic paralysis terminated with intravenous propranolol. Ann Emerg Med. 1994;24(4):736–740.

2. Birkhahn RH, Gaeta TJ, Melniker L. Thyrotoxic periodic paralysis and intravenous propranolol in the emergency setting. J Emerg Med. 2000;18(2):199–202.

3. Lin SH, Lin YF. Propanolol rapidly reverses paralysis, hypokalemia, and hypophosphatemia in thyrotoxic periodic paralysis. Am J Kidney Dis. 2001;37(3):620–623.

4. Huang TY, Lin SH. Thyrotoxic hypokalemic periodic paralysis reversed by propranolol without rebound hyperkalemia. Ann Emerg Med. 2001;37(4):415–416.

5. Yeung RT, Tse TF. Thyrotoxic periodic paralysis: effect of propranolol. Am J Med. 1974;57(4):584–590.