Carbamazepine is hard to like: it induces CYP3A4 and itself, interacts with a huge number of drugs and takes a long time to reach a steady level, so there are few patients who cannot be moved to something else. It also carries Stevens-Johnson and teratogen risks, so treat it more like valproate.
Why we rarely reach for it
Too many drug interactions: it interacts with a huge number of other medications and with itself, so it takes forever to get to level. There are very few patients for whom you cannot justify a different medication.
“it's got too many drug-drug interactions, interacts with like a billion different other medications, and it interacts with itself. It's got a personality disorder. I hate it. So it takes forever to get to level”
52:45Mood Stabilizers for Bipolar Disorder: Lithium, Lamotrigine, Depakote & MoreJul 2026 Also said in 1 more episode
“it causes SIP3A4 induction, and then it causes auto induction. So it's just, it's really problematic with regards to drug-drug interactions. There's very few patients that you can't justify a different medication rather than using carbamazepine”
53:08Mood Stabilizers for Bipolar Disorder: Lithium, Lamotrigine, Depakote & MoreJul 2026
Dosing and titration
Head for 600 mg from the start, but get there slowly: 200 mg steps, or 100 mg steps from zero to 600 if you want to be extra careful and are not in a hurry.
“You have to head for 600 from the get-go and get there quite slowly. A 200 milligram pill, or if I'm really anxious and I really want to make sure that the patient doesn't have trouble with this and we're not in a super big hurry, A 100 milligram increments from zero to 600”
53:38Dr. Jim Phelps’ Bipolar Treatment Tier List: Lessons from 30+ Years in PsychiatryJul 2026Guest episode
Side effects and safety
It can cause Stevens-Johnson syndrome and it is a teratogen, so using it in women of reproductive age is a different ballgame. Start thinking of it more like valproate.
“Yes, it can cause Stevens-Johnson syndrome. Yes, it is a teratogen. So using it in reproductive age women is a whole different ballgame. So we should start thinking of it a little bit more like valproid”
55:12Dr. Jim Phelps’ Bipolar Treatment Tier List: Lessons from 30+ Years in PsychiatryJul 2026Guest episode Some ethnic groups carry a higher Stevens-Johnson risk with lamotrigine, oxcarbazepine and carbamazepine, and there is genetic testing for the high-risk gene.
“There are ethnic groups that will have a higher risk of SJS, Steven Johnson syndrome, to lamotrigine, oxcarbazepine, carbamazepine, those kinds of things. Okay. And there is testing available to see if they have the gene that puts them at particularly high risk”
48:28Mood Stabilizers for Bipolar Disorder: Lithium, Lamotrigine, Depakote & MoreJul 2026
Monitoring
For an Asian patient, the FDA recommends testing for HLA-B 15 before carbamazepine.
“If you have an Asian patient, FDA recommends testing for the HLIB 15 for carbamazepine”
49:07Mood Stabilizers for Bipolar Disorder: Lithium, Lamotrigine, Depakote & MoreJul 2026
It also comes up on
- Bipolar disorderOxcarbazepine has old, mixed evidence, but its action is meaningfully close to carbamazepine's.
- Mood stabilizersThe core list: lithium, Depakote, lamotrigine, carbamazepine and oxcarbazepine.
- OxcarbazepineThe evidence is old and mixed and people say they do not like it, but there is at least some, and its action is meaningfully close to carbamazepine.
From these episodes
Every point above is something said on the Psychofarm podcast, with the words as spoken and a link to the moment in the episode. It is education, not medical advice, and an episode reflects what we thought when we recorded it.