- Chlorphenamine tablets 4mg; syrup 2mg/5mL

• 1 month - 2 years, 1mg twice daily.


• 2 - 6 years, 1mg every 4-6 hours; max 6mg daily.


• 6 - 12 years, 2mg every 4-6 hours; max 12mg daily.


• 12 - 18years, 4mg every 4-6 hours; max 24mg daily.

• 1 month - 1 year, 250 micrograms/kg, max 2.5mg.
• 1 - 6 years, 2.5-5mg.
• 6 - 12 years, 5-10mg


• 12 - 18 years, 10-20mg.



Repeated if required up to 4 times in 24 hours.

• Under 2 years, 0.25mg/kg twice daily.
• 2 - 6 years, 5mg daily or 2.5mg twice daily.
• above 6 years, 10mg daily or 5mg twice daily.

• Antihistamines may be of value in the treatment of nasal allergies, especially hay fever, and vasomotor rhinitis. They reduce rhinorrhoea and sneezing but are usually less effective for nasal congestion.

• Oral antihistamines are of value in preventing urticaria and are used to treat urticarial rashes, pruritus, and insect bites and stings; they are also used in drug allergies.

• Cetirizine causes less sedation than chlorphenamine but is more expensive; both are available over-the-counter.

• First choice preparation for allergic rhinitis is beclometasone nasal spray (see section 12.2.1).

- Adrenaline 1 in 1000 (1mg/mL) injection

• Under 6 months, 50micrograms (0.05mL) by intramuscular injection repeated after 5 minutes as necessary.


• 6 months-6 years, 120micrograms (0.12mL) by intramuscular injection repeated after 5 minutes as necessary.


• 6-12 years, 250micrograms (0.25mL) by intramuscular injection repeated after 5 minutes as necessary.


• Above 12 years, 500micrograms (0.5mL) by intramuscular injection repeated after 5 minutes as necessary.

- Adrenaline for self-administration EpiPen® Jr Auto-injector 0.15mg or EpiPen® Auto-injector 0.3mg consisting of a fully assembled syringe and needle delivering adrenaline 150micrograms or 300micrograms respectively by intramuscular injection

• 6 months-6 years, 150micrograms by intramuscular injection repeated after 5 minutes as necessary.


• 6-18 years, 300micrograms by intramuscular injection repeated after 5 minutes as necessary.

- Chlorphenamine injection 10mg/mL

• 1 Month - 1 year, 250micrograms/kg by intravenous injection.


• 1-6 years, 2.5-5mg by intravenous injection.


• 6-12 years, 5-10mg by intravenous injection.


• 12-18 years, 10-20mg by intravenous injection.

- Hydrocortisone sodium succinate injection 100mg

• Up to 1 year, 25mg by intravenous injection.


• 1-5 years, 50mg by intravenous injection.


• 6-12 years, 100mg by intravenous injection.


• 12-18 years, 100-300mg by intravenous injection.

• Adrenaline should be given immediately for an acute anaphylactic reaction (laryngeal oedema, bronchospasm and hypotension). Patients given adrenaline should attend hospital by ambulance.

• Chlorphenamine injection is a useful adjunctive treatment given after adrenaline injection and continued either orally or by injection for 24-48 hours to prevent relapse.

• Hydrocortisone injection should be given after adrenaline and chlorphenamine in the initial management of anaphylactic shock. Its onset of action is delayed for several hours but it prevents further deterioration in severely affected patients. If intravenous access is not available, then the intramuscular route may be used.

• Atopic individuals are particularly at risk of anaphylactic reactions; patients with known severe allergy to insect stings, foods or peanuts should carry, and receive instruction for the use of, prefilled syringes (e.g. EpiPen®) for self-administration. Patients should be prescribed two for each site, for example nursery and home.