UK Clinical Pharmacy Association

Ketotifen

Issues for surgery

Loss of symptomatic relief of hay fever and allergic rhinitis if omitted.

Advice in the perioperative period

Elective and emergency surgery 

Continue.

For ketotifen eyedrops

Continue, unless the patient is undergoing ophthalmology surgery and the ophthalmologist requests for them to be withheld. 

Post-operative advice

If taken regularly, restart post-operatively once enteral intake resumed, otherwise restart if symptoms develop.

For ketotifen eye drops

Restart post-operatively when next administration is due, unless the patient has undergone ophthalmology surgery and the ophthalmologist requests for them to be withheld.

Interactions with common anaesthetic agents

Systemic absorption can follow topical application of ketotifen to the eyes – the possibility of interactions listed for oral ketotifen should be considered.

CNS depression

See also Interactions with other common medicines used in the perioperative period.

Ketotifen has CNS depressant effects which may be additive with other medicines that also have CNS depressant effects such as:

  • benzodiazepines
  • inhalational anaesthetics and intravenous anaesthetics
  • local anaesthetics
  • opioids

(Consult British National Formulary for available drugs in each class)

Interactions with other common medicines used in the perioperative period

Systemic absorption can follow topical application of ketotifen to the eyes – the possibility of interactions listed for oral ketotifen should be considered.

CNS depression

See also Interactions with common anaesthetic agents.

Ketotifen has CNS depressant effects which may be additive with other medicines that also have CNS depressant effects such as:

  • antiemetics (e.g. cyclizine, prochlorperazine)
  • opioids

(Consult British National Formulary for available drugs in each class)

Further information

None relevant.

References

Baxter K, Preston CL (eds), Stockley’s Drug Interactions (online) London: Pharmaceutical Press. http://www.medicinescomplete.com [Accessed on 2nd October 2023]

Joint Formulary Committee. British National Formulary (online) London: BMJ Group and Pharmaceutical Press. http://www.medicinescomplete.com [Accessed on 2nd October 2023]

Summary of Product Characteristics – Zaditen® (ketotifen fumarate) 0.25 mg/ml, eye drops, solution. Thea Pharmaceuticals Ltd. Accessed via www.medicines.org.uk 21/01/2024 [date of revision of the text October 2020]