Allergan Syrup

Promethazine is a phenothiazine derivative which blocks postsynaptic mesolimbic dopaminergic receptors in the brain. It exhibits strong α-adrenergic blocking effect and depresses the release of hypothalamic and hypophyseal hormones. It competes with histamine for the H1-receptor; muscarinic blocking effect may be responsible for antiemetic activity. It also reduces stimuli to the brainstem reticular system.


Promethazine Hydrochloride Syrup is used for:

  • Allergic conditions
  • Nasal allergy & congestion
  • Urticaria
  • Hay fever
  • Angioneurotic edema
  • Drug reaction or hypersensitivity
  • Sedation
  • Nausea & Vomiting
  • Sedative and drying effects in anesthesia and obstetrics
  • Symptomatic relief of cough and cold (Specially in children)
  • Bronchial asthma
Trade Name Allergan
Generic Promethazine Hydrochloride (Syrup)
Weight 5mg/5ml
Type Syrup
Therapeutic Class Anti-emetic drugs, Miscellaneous sedatives & hypnotics, Sedating Anti-histamine
Manufacturer Cipla Ltd
Available Country Bangladesh
Last Updated: June 23, 2021 at 11:24 am


Allergan dosage

Adults (including elderly): 25 mg at night increased to 25 mg twice daily if necessary or 10-20 mg 2-3 times daily.


  • Under 2 years: it is not recommended.
  • 2-5 years: 5-15 mg daily in 1-2 divided doses,
  • 5-10 years: 10-25 mg daily in 1-2 divided doses.

Side Effects

Common side effects are drowsiness, dryness of mouth & skin, gastro-intestinal disturbances.


Promethazine Hydrochloride may cause drowsiness. If affected, patients should be advised not to drive or operate machinery. Alcohol and certain other CNS depressants can potentiate the sedative effects of this antihistamine and patient should be warned of these effects.

Pregnancy & Breastfeeding use

Promethazine should be used in pregnancy only if the potential benefits justifies the potential risks to the foetus. It is not known whether Promethazine Hydrochloride is excreted in human milk. A decision should be made whether to discontinue nursing or to discontinue the drug taking into account the importance of the drug to the mother.


Promethazine Hydrochloride Syrup is contraindicated in patients with hypersensitivity to the drug and patients with ventilatory impairment.

Storage Condition

Store in a cool, dry place, away from light. Keep out of the reach of children.

Allergan contains Promethazine Hydrochloride (Syrup) see full prescribing information from innovator Monograph