Medical Surgical Myasthenia Gravis MG #4

Question

A client with myasthenia gravis has developed strep throat and a lower respiratory tract infection. Which medication below would be the safest choice for the client?

Answers

  1. Levofloxacin
    • Rationale:

      This answer is not correct because levofloxacin is a cephalosporin that comes with several black box warnings. Cephalosporins are contraindicated in clients with myasthenia gravis due to their neuromuscular blocking activity which results in muscle weakness.

  2. Azithromycin
    • Rationale:

      This answer is not correct because aminoglycosides like azithromycin should be avoided due to the inhibition of acetylcholine release. Myasthenia gravis requires acetylcholine to aid in voluntary muscle strength.

  3. Propranolol
    • Rationale:

      This answer is not correct since propranolol is not an antibiotic. This will cause fatigue in the MG client who already experiences fatigue due to their disease. Beta Blockers are known to cause fatigue and weakness.

  4. Amoxicillin
    • Rationale:

      This answer is correct because amoxicillin is safe to use in clients with myasthenia gravis. Amoxicillin is a penicillin and works as an antibiotic by bursting the cell walls of bacteria. There is no contraindication or cautionary use for clients with myasthenia gravis.

Overview

There are many medications that should be avoided in clients with myasthenia gravis. These drugs can exacerbate myasthenia gravis which could result in a requirement of respiratory support.

Explanation

Learning Outcomes

Myasthenia gravis is a chronic autoimmune neuromuscular disease that causes weakness in skeletal muscles. There are many medications that should be avoided in clients with myasthenia gravis. These drugs can exacerbate myasthenia gravis which could result in a requirement of respiratory support. Cephalosporins are contraindicated in clients with myasthenia gravis due to their neuromuscular blocking activity which results in muscle weakness. Azithromycin should be avoided due to the inhibition of acetylcholine release. Myasthenia gravis requires acetylcholine to aid in voluntary muscle strength. Beta blockers are known to cause fatigue and weakness in clients that are already experiencing fatigue and weakness.

Test Taking Tip

Know black box warnings of medications. Know your drug classes.

Video Rationale