The lowest standard dose of sertraline is 25 mg per day. This is the smallest tablet manufactured and the recommended starting dose for several conditions, including panic disorder, PTSD, and social anxiety disorder. For depression, the starting dose is typically 50 mg, but doctors often prescribe 25 mg for the first week to ease the body into the medication before increasing.
Starting Doses by Condition
Sertraline isn’t one-size-fits-all. The FDA-approved starting dose depends on what it’s being prescribed for:
- Major depressive disorder: 50 mg per day
- Obsessive-compulsive disorder (adults): 50 mg per day
- OCD in children ages 6 to 12: 25 mg per day
- Panic disorder, PTSD, and social anxiety disorder: 25 mg per day
For panic disorder, PTSD, and social anxiety, the plan is usually to start at 25 mg for one week and then increase to 50 mg based on how you respond and tolerate it. That initial week at 25 mg helps your body adjust gradually, which can reduce early side effects like nausea, headache, or sleep changes.
Available Tablet Strengths
Sertraline tablets come in three strengths: 25 mg, 50 mg, and 100 mg. All three are scored, meaning they have a line down the middle so you can split them in half. Splitting a 25 mg tablet gives you 12.5 mg, which some prescribers use informally when starting patients who are especially sensitive to medications, though 12.5 mg is not an FDA-recognized therapeutic dose.
There’s also an oral liquid concentrate available at 20 mg per milliliter. This form allows for very precise dosing in small increments, which is particularly useful for children, people who have difficulty swallowing tablets, or anyone who needs to taper off the medication very gradually.
Does 25 mg Actually Work?
Clinical trials have not shown a clear dose-response relationship for sertraline between 50 mg and 200 mg per day. In other words, higher doses don’t reliably produce better results across study populations. The therapeutic range begins at 50 mg for most conditions, and 25 mg is considered a transitional dose rather than a long-term treatment dose in most cases.
That said, some people do find that 25 mg provides meaningful relief, particularly for anxiety. Individual responses to antidepressants vary widely, and if 25 mg is working for you, that’s a conversation worth having with your prescriber rather than assuming you need to increase. The medication reaches steady levels in your bloodstream after about one week of daily use, with a half-life of roughly 26 hours, so it takes at least a few weeks at any dose to judge its full effect.
Why Some People Start Even Lower
Though 25 mg is the lowest manufactured tablet, some doctors prescribe half of that (12.5 mg) for the first few days. This is common for people who have a history of being sensitive to medications, those with anxiety disorders (where SSRIs can temporarily increase anxiety before improving it), or older adults who metabolize drugs more slowly. There are no formal guidelines for a 12.5 mg dose, but it’s a widely used clinical practice to minimize startup side effects.
The liquid form makes sub-25 mg dosing straightforward without the imprecision of splitting small tablets.
Low Doses During Tapering
The lowest dose of sertraline a person takes isn’t always at the start of treatment. When stopping the medication, gradual dose reduction helps prevent withdrawal symptoms like dizziness, irritability, and electric shock sensations sometimes called “brain zaps.” Sertraline is classified as having the lowest potential risk for withdrawal symptoms among antidepressants, but some people still need a very slow taper.
The Royal College of Psychiatrists notes that some people need to reduce to as low as 2% of their original dose before stopping completely. For someone on 100 mg, that would mean tapering down to 2 mg, which requires the liquid formulation. Even at very low doses, withdrawal symptoms can still occur when you stop entirely. If symptoms return during tapering, the typical approach is to go back to the last tolerable dose and reduce more slowly from there.
What This Means in Practice
If you’ve been prescribed 25 mg, you’re on the lowest standard dose. It’s a common and appropriate starting point, especially for anxiety-related conditions. Most people will eventually move to 50 mg or higher, but the timeline for any increase is flexible. Sertraline doses can be adjusted in increments of 25 to 50 mg, with at least one week between changes to allow your body to adjust. The maximum approved dose is 200 mg per day for adults.
If you’re concerned about side effects or feel that even 25 mg is too much, the liquid formulation gives you and your prescriber the flexibility to work with smaller amounts. Starting low and increasing slowly is one of the most reliable ways to find the dose that works without unnecessary discomfort along the way.