Amisulpride, Aripiprazole, Asenapine, Cariprazine, Lurasidone, Paliperidone, Olanzapine, Quetiapine, Risperidone
[For Clozapine – see separate monograph]
Issues for Surgery
Risk of withdrawal if omitted (see Further Information).
Risk of relapse of schizophrenia or bipolar disorder if omitted.
Risk of Intraoperative Floppy Iris Syndrome (IFIS) in patients undergoing cataract surgery when paliperidone or risperidone continued (see Further Information).
Advice in the Perioperative period
Elective and Emergency Surgery
For patients taking olanzapine who may decide to quit smoking during the perioperative period see Further Information.
Patients taking Paliperidone or Risperidone and Undergoing Cataract Surgery
If a long Nil by Mouth (NBM) period is anticipated, or if there are concerns regarding enteral absorption, advice on alternative preparations / routes should be sought from a Psychiatrist.
Patients taking Lurasidone
Patients receiving depot antipsychotic preparations
Interaction(s) with Common Anaesthetic Agents
Central Nervous System (CNS) Depression (also see under Interaction(s) with other Common Medicines used in the Perioperative Period)
Atypical antipsychotics have CNS depressant effects which may be additive with other medicines that also have CNS depressant effects such as1, 2, 6, 7, 8, 9, 10, 11:-
(Consult British National Formulary for available drugs in each class)
With the exception of amisulpride, atypical antipsychotics can increase the risk of hypotension when used concomitantly with inhalational and intravenous anaesthetics6.
Interaction(s) with other Common Medicines used in the Perioperative Period
CNS Depression (also see under Interaction(s) with Common Anaesthetic Agents for information on opioids)
Atypical antipsychotics have CNS depressant effects which may be additive with antiemetics that also have CNS depressant effects such as cyclizine, droperidol and prochlorperazine, 1, 2, 6, 7, 8, 9, 10, 11.
With the exception of amisulpride, atypical antipsychotics can increase the risk of hypotension when used concomitantly with droperidol and prochlorperazine6.
Dexamethasone and hydrocortisone may cause hypokalaemia (potentially increasing the risk of torsades de pointes) with amisulpride, paliperidone or risperidone – use with caution6, 7, 12. If hypokalaemia occurs, corrective action should be taken and QT-interval monitored.
Co-administration of atypical antipsychotics, particularly amisulpride, paliperidone or risperidone, with medicines known to prolong the QT-interval must be based on a careful assessment of the potential risks and benefits for each patient since the risk of torsade de pointes may increase1, 2, 3, 4, 6, 7, 12.
Medicines that may be used in the perioperative period that are known to prolong the QT-interval include6, 12: -
*monitor ECG with concurrent use if risk factors for QT-interval prolongation also present (increasing age, female sex, cardiac disease, and some metabolic disturbances e.g. hypokalaemia)
Antimicrobials (see also QT-Interval Prolongation above)
Whilst single surgical prophylactic doses should not pose a problem, monitor for side effects and consider reducing atypical antipsychotic dose if a prolonged course of clarithromycin or ciprofloxacin is required and monitor full blood count if a prolonged course of myelosuppressive medication is required.
Abrupt withdrawal of antipsychotics may result in symptoms including sweating, insomnia, tremor, anxiety, nausea and vomiting7, 10.
Tobacco is known to induce CYP1A2 resulting in reduced olanzapine plasma concentrations in smokers; this is thought to have limited clinical consequences6, 10. If a patient taking olanzapine decides to quit smoking during the perioperative period, they should be advised to report any increase in side effects to the prescriber as dosage adjustments may be necessary. Smoking status is not expected to affect the metabolism of the other atypical antipsychotics covered in this monograph1, 2, 3, 4, 5, 7, 8, 9, 13, 14.
Venous Thromboembolism (VTE)
Cases of VTE have been reported with antipsychotic drugs, although a causal relationship has not been established10. Patients with schizophrenia often have acquired risk factors for VTE; identify any risk factors and consider if thromboprophylaxis is indicated post-operatively1, 2, 3, 4, 5, 10, 13, 14.
Intraoperative Floppy Iris Syndrome (IFIS)
IFIS has been observed during cataract surgery in some patients on or previously treated with tamsulosin. Isolated reports have also been received with other alpha-adrenoceptor blockers and the possibility of a class effect cannot be excluded. As IFIS may lead to increased procedural complications during the cataract operation current or past use of medications with alpha-adrenoceptor blocking activity, including paliperidone and risperidone, should be made known to the ophthalmic surgeon in advance of surgery1, 2, 3, 4.