Lamotrigine

  Issues for Surgery

For epilepsy – precipitation of rebound seizures or status epilepticus if omitted.

For treatment of bipolar disorder – risk of rebound bipolar symptoms.

  Advice in the Perioperative period

Elective and Emergency Surgery

Continue.

Patients should be advised to take their regular medications on the day of surgery^{1, 2, 3.}

Abrupt withdrawal of any anticonvulsant drug should be avoided¹.

Confirm with the patient if they need to be maintained on a specific manufacturer’s product (see Further Information).

Post-operative Advice

Regular dosing of the patient’s usual oral medication should be re-established as early as possible post-operatively^{2, 3}.

Lamotrigine is only available as oral preparations. If patients cannot resume their usual oral medication post-operatively, the advice of a Neurologist (for epilepsy patients) or Psychiatrist (for bipolar patients), should be sought to determine the most appropriate preparation, dose, route and frequency to be used.

Monitor renal function – refer to specialist information for dosing recommendations if renal impairment occurs post-operatively.

  Interaction(s) with Common Anaesthetic Agents

For general information regarding the use of anaesthetic agents in epilepsy patients – see ‘Antiepileptics – A General Overview’.

Central Nervous System (CNS) Depression (also see under Interaction(s) with other Common Medicines used in the Perioperative Period)

Lamotrigine has CNS depressant effects which may be additive with other medicines that also have CNS depressant effects such as¹:-

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

*NB: Tramadol should be avoided in patients with a history of epilepsy due to an increase in seizure risk¹.

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

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

For general information regarding the use of antiemetics in epilepsy patients – see ‘Antiepileptics – A General Overview’.

CNS Depression (also see under Interaction(s) with Common Anaesthetic Agents for information on opioids)

Lamotrigine has CNS depressant effects which may be additive with antiemetics that also have CNS depressant effects such as cyclizine, droperidol and prochlorperazine*¹.

*NB: see ‘Antiepileptics – A General Overview’

  Further Information

MHRA/CHM Advice: Antiepileptic Drugs: updated advice on switching between different manufacturer’s products for a particular drug (November 2017)¹

Epilepsy
Lamotrigine is a category 2 antiepileptic, hence the need for continued supply of a particular manufacturer’s product should be based on clinical judgement and consultation with the patient and / or carer taking into account factors such as seizure frequency treatment history, and potential implications to the patient having a breakthrough seizure. Non-clinical factors such as patient anxiety, confusion, potential for dosing errors should also be considered (For more information see ‘Antiepileptics – A General Overview’).

Other Indications
There is no specific advice available for maintaining patients on a specific manufacturer’s product for indications other than epilepsy.

Skin Reactions

Serious skin reactions including Steven-Johnson syndrome and toxic epidermal necrolysis have developed during treatment with lamotrigine; most rashes occur within the first 8 weeks of treatment^{1, 4}. Rash is sometimes associated with hypersensitivity syndrome. Consider withdrawal if serious rash or signs of hypersensitivity syndrome develop¹. If withdrawal of the drug is necessary, consult a Neurologist / Psychiatrist to ensure that an appropriate management plan is in place.

  References

1. Joint Formulary Committee. British National Formulary (online) London: BMJ Group and Pharmaceutical Press http://www.medicinescomplete.com [Accessed 3^rd July 2019]
2. Perks A, Cheema S, Mohanraj R. Anaesthesia and epilepsy. BJA: British Journal of Anaesthesia. 2012; 108(4):562-571
3. Carter EL, Adapa RM. Adult epilepsy and anaesthesia. BJA Education. 2015; 15(3):111-117
4. Summary of Product Characteristics – Lamotrigine Mylan 100 mg Tablets. Mylan. Accessed via www.medicines.org.uk 15/08/2019 [date of revision of the text November 2018]