I believe my patient would benefit from antidepressant therapy. What recommendations can you offer about selecting an initial agent-and about amending the regimen if the response is suboptimal?
There is no specific test to help select the best antidepressant for a given patient. You simply have to choose an agent, start at the standard dosage, and give the drug enough time to work.
Before the patient starts taking any antidepressant, it is essential that you and he or she write up a list of symptoms, signs, and behaviors related to the depression that you want the medication to target. Tell your patient that you will want to see him in 4 to 6 weeks after he starts treatment to see how well he is doing.
The antidepressants with the fewest side effects are the SSRI’s [eg, sertraline (Zoloft), citalopram (Celexa), paroxetine (Paxil), and fluoxetine (Prozac)]. These are a generally good place to start.
If significant elements of the depression still remain after 4 to 6 weeks of SSRI therapy, double the dose of the drug and reassess in another 4 to 6 weeks. If, at the second followup, elements of depression are still present, switch to another SSRI and repeat the process.
If the response is inadequate at this point, consider adding a drug from a different class, such as bupropion (Wellbutrin) or a norepinephrine reuptake inhibitor (NRI) to the second SSRI. (The SSRI dosage is maintained as the second agent is added.)
Alternately, consider adding a second generation antipsychotic, such as aripriprazole (Abilify) or quetiapine (Seroquel) instead of an NRI. Yet another possibility would be to switch to a serotonin-norephinephrine reuptake inhibitor (SNRI), such as venlafaxine (Effexor) or duloxetine (Cymbalta).
If the patient is still experiencing elements of depression after 4 to 6 weeks despite these manipulations in the regimen, a psychiatric consultation or referral a psychiatrist is warranted.