Many of patients with depression do not respond to their first anti depression medications. Response to these medications may be under genetic influence. In addition, the genetic profile of individuals may explain the differences in response to some of anti-seizure, anti- anxiety medications as well as other medications commonly used to treat neurological and psychiatric conditions.
Neurological and Psychiatric Medications
| Medication | Gene |
| Carbamazepine, Oxcarbazepine, Phenytoin, Fosphenytoin | HLA-B*1502 |
| Phenytoin, Siponimod, Fosphenytoin | CYP2C9 |
| Brivaracetam, Moclobemide, Clobazam, Sertraline, Citalopram, Escitalopram, Diazepam, Amitriptyline, Clomipramine, Doxepin, Trimipramine, Imipramine | CYP2C19 |
| Trazodone, Guanfacine, Eszopiclone, Alprazolam, Buspirone, Clonazepam, Cyclosporine, Quetiapine | CYP3A4, CYP3A5 |
| Sertraline | CYP2B6 |
| Bupropion | ANKK1 |
| Methylphenidate, Clonidine | ADRA2A |
| Dextroamphetamine, Methylphenidate, Lisdexamfetamine, Dexmethylphenidate, Amphetamine | COMT |
| Oxazepam, Lorazepam | UGT2B15 |
| Succinylcholine | BCHE |
| Haloperidol, Olanzapine, Iloperidone, Aripiprazole, Aripiprazole Lauroxil, Pimozide, Risperidone, Thioridazine, Perphenazine, Clozapine, Brexpiprazole, Zuclopenthixol, Mirtazapine, Amitriptyline, Vortioxetine, Venlafaxine, Clomipramine, Desipramine, Doxepin, Duloxetine, Protriptyline, Flupenthixol, Nortriptyline, Fluvoxamine, Paroxetine, Fluoxetine, Donepezil, Fesoterodine, Tolterodine, Atomoxetine, Tetrabenazine, Galantamine, Dextromethorphan-Quinidine, Sertindole, Cevimeline, Amphetamine, Dapoxetine, Amoxapine, Trimipramine, Imipramine, Pitolisant, Tolperisone, Deutetrabenazine, Valbenazine | CY2D6 |
Frequency of Cytochrome P450 (CYP2D6, CYP2C9, CYP2C19) Metabolizer Types in the population
| Cytochrome | Poor metabolizer | Intermediate metabolizer | Normal metabolizer | Rapid or ultra-rapid metabolizer |
| CYP2D6 | 4-7% | 9-35% | 50-90% | 2-3% |
| CYP2C9 | 3% | 30% | 68% | N/A |
| CYP2C19 | 2-20% | 24-36% | 14-44% | 30% |