Issues for surgery
For treatment of hypertension – loss of blood pressure (BP) control if omitted.
For treatment of angina – exacerbation of angina if omitted.
Risk of hypotension when continued.
Advice in the perioperative period
Elective and emergency surgery
Continue.
EXCEPT:
- Combination products containing amlodipine and olmesartan, follow advice as for olmesartan - see Olmesartan monograph
- Combination products containing amlodipine and hydrochlorothiazide and olmesartan - also see Hydrochlorothiazide monograph and follow advice for olmesartan - see Olmesartan monograph
- Combination products containing amlodipine and hydrochlorothiazide and valsartan - also see Hydrochlorothiazide monograph and follow advice for valsartan - see Valsartan monograph
Consideration should be given to prescribing the components of combination products as separate medicines perioperatively.
Post-operative advice
Restart post-operatively when next dose is due.
Monitor BP.
Interactions with common anaesthetic agents
Inhalational Anaesthetics
See also Hypotension below.
Amlodipine may reduce the minimum alveolar concentration (MAC) of inhalational anaesthetics by up to 20%.
Hypotension
Amlodipine can increase the risk of hypotension when used concomitantly with remifentanil or inhalational / intravenous anaesthetics..
Neuromuscular blocking drugs (NMBDs)
Amlodipine may prolong neuromuscular blockade when used concomitantly with NMBDs. The clinical significance is unknown, but bear the potential interaction in mind in case of unexpected response to treatment.
Interactions with other common medicines used in the perioperative period
Hypotension
Amlodipine can increase the risk of hypotension when used concomitantly with droperidol or prochlorperazine.
Macrolide antibiotics
Macrolide antibiotics (e.g. clarithromycin, erythromycin), which are inhibitors of CYP3A4, may increase the effects of amlodipine leading to hypotension and, for verapamil and diltiazem, bradycardia. Monitor the patient and consider reducing the dose of the amlodipine if necessary.
Whilst single surgical prophylactic doses should not pose a problem, continued post-operative treatment may require close monitoring. Consult current product literature.
Further information
None relevant.
References
Baxter K, Preston CL (eds), Stockley’s Drug Interactions (online) London: Pharmaceutical Press. http://www.medicinescomplete.com [Accessed on 12th April 2019]
British National Formulary (online) London: BMJ Group and Pharmaceutical Press. http://www.medicinescomplete.com [Accessed on 12th April 2019]
The Joint Task Force on non-cardiac surgery: cardiovascular assessment and management of the European Society of Cardiology (ESC) and the European Society of Anaesthesiology (ESA). 2014 ESC/ESA Guidelines on non-cardiac surgery: cardiovascular assessment and management. European Heart Journal. 2014; 35:2383-2431
Scarth E, Smith S. Drugs in Anaesthesia and Intensive Care, 5th Edition. Oxford University Press; 2016
Summary of Product Characteristics – Amlodipine 10 mg tablets. Accord Healthcare Limited. Accessed via www.medicines.org.uk 09/10/2019 [date of revision of the text August 2018]