There are five different classes of antidepressant medicines and all seem to work equally well in the studies. They are: the Selective Serotonin Reuptake Inhibitors (SSRIs), the Serotonin Norepinephrine Reuptake Inhibitors (SNRIs), the tricyclic antidepressants, the Monomine Oxidase Inhibitors (MAOIs), and the others (miscellaneous) antidepressants class.
However, because each person is different, one antidepressant may work better for one person and a different antidepressant might work better for another person. That’s why you shouldn’t give up if the first medicine you use doesn’t give you all the relief you need.
Also if one or two antidepressants from one class have not helped a patient, the doctor might suggest an antidepressant from a different class as medicines from one class may be more effective for a given patient than from another class.
But which one of the all the different medicines should you go with? A recent Lancet meta-analysis recommended sertraline or citolopram as the best first choice of all the available antidepressants. However, since that 2009 article, the FDA on August 24, 2111 warned that citolopram should not be prescribed in doses of greater than 40 mg per day and that it can cause QT interval prolongation. The FDA further recommended that citolopram not be used in patients with congenital long QT syndrome, congestive heart failure, bradyarrythmias, hypokalemia or hypomagnesemia because these patients are at increased torsade de pointes (a potentially fatal cardiac arrythmia).
So you and your doctor decide to begin sertraline. Start with 50 mg once daily usually in the morning with food. Begin with 25 mg once daily as before in the elderly.
You should plan on seeing your doctor at 2 weeks, 4 weeks, 6 weeks, 9 weeks, and 12 weeks according to the recommendations of the Texas Medication Algorithm Project Depression manual. Your doctor may want to see you weekly if your depression is severe. Also if you have suicidal thoughts, your doctor may need to see you more frequently, either in the office or by phone.
See the TMAP Depression Manual at https://www.pbhcare.org/pubdocs/upload/documents/TMAP%20Depression%202010.pdf
The key to success in treating depression is to give the medicine enough time to work and also to give enough of the medicine for it to work. It takes 8 to 12 weeks to see if the antidepressant is going to help so you have to stick with the program. If you are able to tolerate the medicine and your not having any significant (unbearable) side effects then you and your doctor should increase your medicine every two to three weeks until one of three things happen:
First, your symptoms go away. The goal of modern depression treatment is to get rid of your depression symptoms, not just get them better. We want your PHQ-9 score to be less than 5. In this case, you should keep taking the medicine for at least six months. Don’t stop the medicine just because you’re better–you’ll just get worse again.
Second, you are taking the maximum recommended dose of your antidepressant if your PHQ score remains too high (your symptoms haven’t gone away). In this case, you and your doctor need to do something different.
Third, as your dose is gradually increased you get side effects to the medicine that you can’t tolerate. So we can’t further increase dose.
Your doctor will start you out at a low dose of your antidepressant and will keep increasing the dose until either your symptoms go away, you reach the maximum recommended dose, or you get side effects to your antidepressant that you can’t tolerate.
Some doctors would recommend trying a different antidepressant if the patient isn’t any better at whatever dose the patient has gotten up to at 4 to 6 weeks. But if you are willing to be patient, other doctors recommend that we keep increasing the dose until we have patient on the maximum recommended dose and the patient has been on that maximum for 4 weeks with a total treatment time on that medicine of 12 weeks (12 weeks from the initial starting dose).
So for sertraline, you would start with 50 mg once daily with food usually in the morning (start 25 mg once daily for the eldery) and stay on that dose for 4 weeks. Then increase dose by 25 to 50 mg once daily every seven days until you get to 100mg once daily. Stay on 100 mg once daily for four weeks. At that time you would consider whether your symptoms have gone away (PHQ-9 of less than 5), or whether you are having any intolerable side effects. If the answer to both questions is no, then you would start increasing the dose again by 25 to 50 mg once daily until either your symptoms are gone (PHQ-9 of less than 5), or you have reached a total dose of 200 mg once daily, or you have gotten side effects you can’t handle.
Each different antidepressant will have different starting and maximum dosage and each may have different times between dosage changes. See Drug Information Guide from the MacArthur Initiative on Depression and Primary Care at
The most important thing is to stick with your program and give time to work and try to get the symptoms of depression gone, not just better. And that often means pushing the medicine to the maximum recommended dose and taking that dose for a long enough time.