Donormyl (Doxylamine succinate) is over-the-counter antihistamine sleeping aid. The sleep-inducing properties of Doxylamine are comparable to that of secobarbital. It is known since 1948.

Donormyl works by inhibiting histamine receptors, thus it is also can be used to alleviate allergy and cold symptoms. Unlike common sleeping pills such as benzodiazepines and benzodiazepine-like drugs, doxylamine is not habit-forming and does not negatively affect sleep quality.

Dosage and administration

The dosage is ½-1 pill a day, 15-30 minutes prior to bedtime. If such dose is ineffective, it can be raised to two pills.

The length of the treatment course is up to 5 days. If you still experience insomnia after the course, you should check with your doctor.

Side effects

  • Constipations
  • Dry mouth
  • Visual accommodation impairment
  • Urinary retention
  • Daytime sleepiness (in this case, consider lowering your dosage)
  • Delirium and hallucinations

Drug interactions

Donormyl does potentiate the depressant effect of sedative antidepressants, barbiturates, benzodiazepines, clonidine, opioids, atipsychotics, anxiolytics, antihistamines, central antihypertensives, thalidomide, baclofen and pizotifen.

Coadministration with muscarinic antagonists increases the risk of adverse effects such as urinary retention, constipations and dry mouth.

Since alcohol does potentiate the sedative effect of most H1 receptor antagonists, you should not take Donormyl with alcohol.


  • Hypersensitivity;
  • Closed angle glaucoma;
  • Prostate and urethral disorders;
  • Lactose intolerance;
  • Age below 15 years old;
  • Pregnancy and lactation.