Question

Drug induced myopathy can be caused by all of the following except:

• A. Atorvastatin.
• B. D-penicillamine.
• C. Ciprofloxacin.
• D. Chloroquine.

Hint:

Ciprofloxacin's musculoskeletal risk is tendon damage, not muscle fiber myopathy.

Answer 1

The Correct Option is C

Drug induced myopathy means muscle fiber damage caused directly by a medicine, showing up as weakness, pain or raised muscle enzymes. The question asks which of four drugs does NOT cause this.

1. Atorvastatin: statins are the most familiar drug cause of myopathy, from mild aches to serious rhabdomyolysis, through direct toxic effects on muscle cells.
2. D-penicillamine: this drug can set off an autoimmune reaction that inflames muscle, producing a picture much like polymyositis.
3. Ciprofloxacin: this fluoroquinolone is best known for harming tendons, especially the Achilles tendon, causing pain, inflammation or even rupture. This is a tendon problem, separate from the muscle fiber itself, so it does not fit as a myopathy cause.
4. Chloroquine: with long term use this drug piles up inside the lysosomes of muscle cells and produces a specific vacuolar myopathy.

Three of the drugs damage muscle fibers directly through toxic or autoimmune mechanisms, while ciprofloxacin's musculoskeletal risk lies in the tendons, not the muscle itself.

Let's summarize:

• Atorvastatin, D-penicillamine and chloroquine each damage muscle tissue by a different route and are established causes of myopathy.
• Ciprofloxacin instead is linked with tendinopathy and tendon rupture, not primary muscle disease.

So the drug that does not cause myopathy here is ciprofloxacin.