Anesthesia Implications

Chronic use of anticonvulsants make patients more tolerant to non-depolarizing agents. This implies a potential increase in dose requirements for the required therapeutic affects.

Side effects include mood disorders, suicidal ideation, Stevens-Johnson syndrome, psychosis, dizziness, and xerophthalmia (dry eyes).

Additional Notes:

Used to treat generalized tonic-clonic seizures.

Therapeutic uses also include improvement of neoplastic plexopathies, peripheral neuropathy, postherpetic neuralgia, and migraine prophylaxis.

Anticonvulsants, in general, may be given after a traumatic brain injury and/or prior to supratentorial craniotomies as prophylaxis against any possible seizures.

OB patients: This drug neither induces nor inhibits enzymes of the CYP cytochrome P450 system. Limited data regarding the pharmokinectic behavior during pregnancy. Animal studies indicate that this drugs is less teratogenic than older agents such as valproate.

Classification: Anticonvulsant

Duration: Half life of 7.1 Hours. Increased with renal impairment

Method of Action: Calcium channel blockade is one certain method of action. However, it appears that this drug has effects on multiple neurotransmitters including glutamine, dopamine, and GABA. The complete method of action remains unclear.

Metabolism: Hepatic (capacity-limited), inactive metabolites

Elimination: Renal (66% unchanged)

References:
Nagelhout. Nurse anesthesia. 5th edition. 2014.
Miller. Miller’s Anesthesia. 2015. p. 915-917
Barash. Clinical anesthesia. 7th edition. 2013. p. 620
Cote. Practice of anesthesia in infants and children. 4th edition. 2009. p. 506
Chestnut. Chestnut’s obstetric anesthesia principles and practice. 5th edition. 2014. p. 1123-1124
Vallerand. Davis’s drug guide for nurses. 15th edition. 2017. p. 761-763