Apomorphine


  Issues for Surgery


Risk of exacerbation of Parkinson’s Disease (PD) and akinesia if omitted1.

Risk of Dopamine Agonist Withdrawal Syndrome (DAWS) if omitted (see Further Information).


  Advice in the Perioperative period


Elective and Emergency Surgery

Continue.

Post-operative Advice

Continue post-operatively at patient’s usual dose.


  Interaction(s) with Common Anaesthetic Agents


For general information regarding the use of anaesthetic agents in PD – see Parkinson’s Disease – A General Overview’.

Hypotension

Apomorphine can increase the risk of hypotension when used concomitantly with inhalational or intravenous anaesthetics2.


  Interaction(s) with other Common Medicines used in the Perioperative Period


QT-Interval Prolongation

Apomorphine, especially at high dose3, is known to cause QT-interval prolongation2, 3. Co-administration of apomorphine with other 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 increase2, 3, 4.

Medicines that may be used in the perioperative period that are known to prolong the QT-interval include2

  • ciprofloxacin*
  • clarithromycin*
  • domperidone – see below
  • erythromycin (especially intravenous)*
  • granisetron*
  • loperamide (increased risk with high doses)*
  • ondansetron*

*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)

Droperidol, haloperidol and prochlorperazine are also known to cause QT prolongation; however, these agents should not be used in PD (see Parkinson’s Disease – A General Overview’).

Domperidone
Pre-treatment with domperidone is essential before apomorphine initiation as it is highly emetogenic; however, ECG monitoring is recommended before starting domperidone, during initiation of apomorphine and whenever clinically indicated thereafter3. The ongoing use of domperidone must be carefully evaluated taking into account any patient factors, which predispose to QT prolongation3.

Antiemetics (see also QT-Interval Prolongation above)

Concurrent use of apomorphine and ondansetron has been associated with profound hypotension and loss of consciousness2, 4; avoid concomitant use of apomorphine and ondansetron, granisetron or other 5-HT3 receptor antagonists4.

Apomorphine can increase the risk of hypotension when used concomitantly with droperidol or prochlorperazine2. However, these medications should be avoided in patients with PD as they exacerbate symptoms2.

For general information regarding the use of antiemetics in PD – see ‘Parkinson’s Disease – A General Overview’.

Hypokalaemia

Dexamethasone and hydrocortisone may cause hypokalaemia; potentially increasing the risk of torsades de pointes when given with apomorphine – use with caution2. If hypokalaemia occurs, corrective action should be taken and QT interval monitored.


  Further Information

 

Withdrawal

Abrupt withdrawal of dopamine agonists is associated with DAWS, which mimics Neuroleptic Malignant Syndrome (NMS).

Prescribing and Administration

Access to the correct medication / formulation at the correct time remains a problem for people with PD whilst they are in hospital5. Delayed doses can have serious implications. PD patients often have complex medication regimes; prescribers should take care to confirm the correct dose, formulation and time of administration with the patient or carer. The time of administration should be documented on the prescription chart and nursing staff should ensure that PD medications are given promptly.


  References


  1. National Institute of Health and Clinical Excellence (2017). NG71 Parkinson’s disease in adults. https://www.nice.org.uk/guidance/ng71 [Accessed on 9th June 2019]
  2. Joint Formulary Committee. British National Formulary (online) London: BMJ Group and Pharmaceutical Press. http://www.medicinescomplete.com [Accessed on 22nd August 2019]
  3. Summary of Product Characteristics – APO-go (apomorphine) PFS 5mg/ml Solution for Infusion in Pre-filled Syringe®. Britannia Pharmaceuticals Limited. Accessed via www.medicines.org.uk 22/08/2019 [date of revision of the text February 2018]
  4. Baxter K, Preston CL (eds), Stockley’s Drug Interactions (online) London: Pharmaceutical Press. http://www.medicinescomplete.com  [Accessed on 22nd August 2019]
  5. Brennan KA & Genever RW. Managing Parkinson’s disease during surgery. BMJ. 2010; 341:c5718