Case File 3

A 53-year-old women comes to see you for a consultation. She is scheduled to take a caribbean cruise in 2 weeks but is concerned about sea sickness. She has been on boats before and is very sensitive to motion sickness. A friend mentioned to her that there is a patch that is effective for this problem. She is in good health and takes no medications regularly. Her examination is normal. You prescribe a scopolamine transdermal patch for her.

Questions 1. What is the mechanism of action of

scopolamine?2. What are the common side effects of

this medication?3. What are some relative

contraindications to its use?

Summary A 53-year-old woman with motion

sickness is prescribed transdermal scopolamine before she takes a sea cruise.

Mechanism of action of scopolamineCompetitive antagonist of

muscarinic cholinoreceptors in the vestibular system and the CNS

Common side effectsMydriasis Dry mouthTachycardiaUrinary retentionConfusionDrowsiness

Relative contraindicationsGlaucomaUrinary

obstructionHeart disease