Hyoscine: Uses, Mechanism of Action, Side Effects and Interactions

It is an alkaloid drug obtained from several plants in the Solanaceae family, including belladonna, henbane, and jimsonweed.

Hyoscine, also called Scopolamine, is derived from a type of Solanaceae known as Scopolia, while the name “Hyoscine” is derived from another type known as Hyoscyamus niger.

Hyoscine medical uses

Scopolamine is an effective remedy for motion sickness, probably due to its ability to depress the central nervous system ( brain and spinal cord ).

Scopolamine is also used to dry secretions and dilate the bronchi during anesthesia, and dilate the pupil during ophthalmic procedures.

It is sometimes used as a premedication (significantly to reduce respiratory tract secretions) to surgery, usually by injection.

Mechanism of action

Like atropine, it has a depressive action on the parasympathetic nerves and, in higher doses, on the autonomic ganglia.

The drug is the most pharmacologically active of several alkaloid substances found in belladonna, in part due to its more excellent solubility, allowing for faster passage to the site of action.


Hyoscine side effects

Side effects include:

  • Dry mouth.
  • Dry or itchy eyes.
  • Drowsiness.
  • Dizziness.
  • Feeling restless
  • Memory problems.
  • Itching or rash.

Who should not use this medicine?

Do not use hyoscine without first checking with your doctor if you have kidney disease, liver disease, an enlarged prostate, difficulty urinating, a stomach obstruction, heart disease, bladder problems, or glaucoma.

Hyoscine passes into breast milk and may harm a nursing baby. Consult your doctor before breastfeeding.

In case of overdose

Call your doctor immediately. Symptoms of a scopolamine overdose include drowsiness, dizziness, agitation, fever, excitability, seizures, hallucinations, coma, and death.

Interactions with other medications

Hyoscine can increase the effects of other drugs that cause drowsiness, such as antidepressants, alcohol, antihistamines (including meclizine), sedatives (used to treat insomnia), pain relievers, anti-anxiety medications, and muscle relaxants.

Tell your doctor about all the medications you are using, and do not use any other prescription or non-prescription medicines without first checking with your doctor.

In addition to the drugs mentioned above, others may also interact with hyoscine. Talk to your doctor and pharmacist before using any prescription or over-the-counter medicine.