Issues for surgery
Loss of symptomatic relief of allergic rhinitis, hay fever and urticaria if omitted.
Risk of QT-interval prolongation if continued.
Advice in the perioperative period
Elective and emergency surgery
Continue.
Post-operative advice
If taken regularly, restart post-operatively as soon as next dose is due; otherwise restart when symptoms develop.
Interactions with common anaesthetic agents
QT-Interval prolongation
Mizolastine has a weak potential to prolong the QT-interval in some individuals, which might be additive with the effects of other drugs that prolong the QT-interval. Concurrent use of mizolastine with other medicines known to prolong the QT-interval e.g. desflurane, isoflurane and sevoflurane, and possibly thiopental, is contraindicated by the UK manufacturer.
Interactions with other common medicines used in the perioperative period
Macrolides
Clarithromycin and erythromycin are predicted to increase the exposure to mizolastine through inhibition of CYP3A4. Concomitant use of clarithromycin or erythromycin is contraindicated by the manufacturers of mizolastine.
QT-Interval prolongation
Mizolastine has a weak potential to prolong the QT-interval in some individuals, which might be additive with the effects of other drugs that prolong the QT-interval. Concurrent use of mizolastine with other medicines known to prolong the QT-interval is contraindicated by the UK manufacturer.
Medicines that may be used in the perioperative period that are known to prolong the QT-interval include:
- ciprofloxacin
- clarithromycin – see also Macrolides above
- domperidone
- droperidol
- erythromycin (particularly intravenous) – see also Macrolides above
- granisetron
- haloperidol
- loperamide (increased risk with high doses)
- ondansetron
- prochlorperazine (theoretical risk)
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 February 2021]
Joint Formulary Committee. British National Formulary (online) London: BMJ Group and Pharmaceutical Press. http://www.medicinescomplete.com [Accessed on 2nd February 2021]
Summary of Product Characteristics – Mizollen (mizolastine) 10 mg modified-release tablets. SANOFI Ltd. Accessed via www.medicines.org.uk 2/2/2021 [date of revision of the text September 2019]