Sedating antihistamines (Formulary)

TAM (Treatments and Medicines) NHS Highland
NHS Highland

HYDROXYZINE - (First line)

Therapy notes

MHRA advice: Hydroxyzine should NOT be prescribed to people with a prolonged QT interval or risk factors for QT interval prolongation (April 2015) (www.gov.uk).

Formulation and dosage details

Formulation:

Tablets 10mg, 25mg

Dosage:

Pruritus: initially 25mg at night, increased if necessary to 25mg 3 to 4 times daily.

Formulation and dosage details

Formulation:

Oral syrup 10mg/5mL unlicensed

Dosage:

Pruritus: initially 25mg at night, increased if necessary to 25mg 3 to 4 times daily.

CHLORPHENAMINE

Therapy notes

Formulation and dosage details

Formulation:

Tablets 4mg

Dosage:

By mouth, adults, 4mg every 4 to 6 hours, maximum 24mg daily. 

Formulation and dosage details

Formulation:

Oral solution 2mg/5mL

Dosage:

By mouth, adults, 4mg every 4 to 6 hours, maximum 24mg daily. 

Formulation and dosage details

Formulation:

Injection 10mg/mL

Dosage:

By subcutaneous or intramuscular injection or by intravenous injection over 1 minute, adults, 10mg; max 40mg in 24 hours.

PROMETHAZINE

Therapy notes

  • For sedation or pre-medication.

Formulation and dosage details

Formulation:

Tablets 10mg, 25mg

Formulation and dosage details

Formulation:

Elixir 5mg/5mL

Editorial Information

Document Id: F358