A client with myasthenia gravis is demonstrating weakness 4 hours after taking the last dose of pyridostigmine (Mestinon). What may be the cause of the client's weakness?

Question

Standard Text: Select all that apply.
1. The client needs a higher dose of the medication.
2. The client is developing drug resistance.
3. The client needs a lower dose of the medication.
4. The client's autonomic nervous system is rejecting the medication.
5. The client should have received the medication with atropine.

Answer 1

Correct Answer: 1,2
Rationale 1: Weakness that occurs 3 or more hours after drug administration without muscarinic overstimulation is more likely due to myasthenic crisis caused by underdosing and is treated with more intensive therapy.
Rationale 2: Weakness that occurs 3 or more hours after drug administration without muscarinic overstimulation is more likely due to myasthenic crisis caused by drug resistance and is treated with more intensive therapy.
Rationale 3: A lower dose of the medication would cause more acute symptoms of weakness.
Rationale 4: Myasthenia gravis is a disease affecting skeletal muscle. It is not a disorder of the autonomic nervous system.
Rationale 5: Atropine is used in the event of muscarinic overstimulation or overdose.
Global Rationale: Weakness that occurs 3 or more hours after drug administration without muscarinic overstimulation is more likely due to myasthenic crisis caused by underdosing or drug resistance and both are treated with more intensive therapy. A lower dose of the medication would cause more acute symptoms of weakness. Myasthenia gravis is a disease affecting skeletal muscle. It is not a disorder of the autonomic nervous system. Atropine is used in the event of muscarinic overstimulation or overdose.