Using medical cannabis and Lamictal may increase side effects such as dizziness, confusion, drowsiness, and difficulty concentrating. Elderly consumers may also experience impairment in judgment. That being said, none of these side effects were proven to result from CBD use per se.
When it comes to interactions between CBD and Lamictal, it can make the medication more or less effective, depending on the dosage.
Combination treatment with CBD and clobazam produced a greater anti-seizure effect than did either treatment alone, but the effect was observed only with a higher, anticonvulsant dose of CBD. A lower dose initiated the pharmacokinetic interaction but did not boost anti-seizure activity.