There are three different kinds of anticonvulsants – sodium channel blockers, GABA active drugs and carbonic anhydrase inhibitors. All three are likely to have different withdrawal profiles. Gabapentin and pregabalin which act on the GABA system have a reputation as being more likely than others to cause problems.
When used for epilepsy some of the risks of withdrawal will often be covered by switching to a drug from a different group. This may or may not help other withdrawal features but is likely to minimize the risk of a seizure.
- Reduce dose by 10-25% per month
- If seizure activity occurs, go back to approximately 75% of the previously tolerated dose
When used for mood stabilization, pain relief, migraine or anxiety based on the effect of missing doses while on treatment, people will often know before starting to withdraw whether there is likely to be a problem.
- If no hints of a problem and if used daily for a month or so reduce dose by a maximum of 25% every week initially or every month if need be.
- If there is any indication of a problem or if used for longer than a month consider tapering more gradually and ideally with the help of a liquid.
Withdrawal Symptoms and Monitoring Guidance
- Initial:Agitation, activation, insomnia, rebound psychosis, withdrawal-emergent abnormal movements, nausea, feeling of discomfort, sweating, vomiting, insomnia, sexual dysfunction
- Protracted: Agitation, pain, dysgeusia, parosmia, food intolerance, insomnia.