Scopolamine

Scopolamine is a tropane alkaloid that blocks muscarinic acetylcholine receptors. It is used chiefly to prevent motion sickness and treat nausea.

Muscarinic acetylcholine receptor: A G protein-coupled receptor activated by acetylcholine and blocked by drugs such as scopolamine. Scopolamine prevents acetylcholine from activating these receptors.
Transdermal patch: A medicated adhesive system that delivers a drug through the skin over an extended period. The patch provides sustained scopolamine delivery for motion-sickness prevention.
Tropane alkaloid: An alkaloid containing a tropane ring, a chemical scaffold found in several plant-derived compounds. Scopolamine belongs to this structural family.
Ondansetron: A serotonin 5-HT3 receptor antagonist used to prevent nausea and vomiting, especially after surgery or chemotherapy. It treats nausea through a different receptor system and generally avoids scopolamine’s anticholinergic effects.
Vestibular system: The sensory system that detects head motion and orientation through structures in the inner ear and brain. Scopolamine dampens vestibular signaling that can trigger motion sickness.
Motion sickness: Nausea, dizziness, or vomiting caused by conflicting signals about movement reaching the brain. Preventing this condition is scopolamine’s best-known use.
Atropine: A tropane alkaloid that blocks muscarinic acetylcholine receptors and is used in several medical settings. It shares scopolamine’s receptor target but differs in clinical effects and uses.
Meclizine: An antihistamine used to prevent and treat motion sickness and vertigo. It is an alternative motion-sickness medicine with a different balance of effects and risks.
Chemoreceptor trigger zone: A brain region that detects blood-borne substances and can activate circuits responsible for vomiting. Antimuscarinic action in nausea pathways helps explain scopolamine’s antiemetic effects.
Postoperative nausea and vomiting: Nausea or vomiting occurring after surgery, often as an effect of anesthesia or analgesic medicines. Scopolamine is sometimes used before surgery to reduce postoperative symptoms.

Linked from 13 pages