Trazodone at 50 mg causes drowsiness in roughly 1 in 4 people, making sedation far and away the most common side effect. At this dose, trazodone is most often prescribed off-label for insomnia rather than depression, so the very effect that makes it useful for sleep can also spill into your waking hours. Beyond drowsiness, a range of other side effects show up in clinical trials, from dry mouth to dizziness, most of them mild and most common during the first week or two of treatment.
The Most Common Side Effects
In clinical trials, these side effects appeared frequently enough that you have a reasonable chance of experiencing at least one:
- Drowsiness and sedation (24 to 41% of users). This is dose-dependent and typically strongest during the first few days.
- Dizziness or lightheadedness (20 to 28%)
- Dry mouth (15 to 34%)
- Headache (10 to 20%)
- Nausea or vomiting (10 to 13%)
- Blurred vision (6 to 15%)
- Nervousness (6 to 15%)
- Fatigue (6 to 11%)
- Constipation (7 to 8%)
Less common effects include nasal congestion (up to 6%), muscle or joint aches (5 to 6%), diarrhea (5%), confusion (5%), tremor (3 to 5%), and mild swelling or skin changes (3 to 7%). Some people lose a small amount of weight, reported in up to 6% of trial participants.
These percentages come from studies across all doses, including higher ones used for depression. At 50 mg, your overall risk for most of these effects is on the lower end of each range, since many side effects scale with dose.
Next-Day Grogginess and Mental Sharpness
One of the biggest practical concerns with trazodone is whether you’ll feel foggy the next morning. The drug has a relatively short active window of about 3 to 6 hours for its sedating effects, which is why researchers have noted it generally doesn’t produce a “hangover” the way longer-acting sleep medications can. That said, the elimination half-life is longer, around 10 to 13 hours, meaning the drug is still clearing your system well into the next day.
In practice, the picture is mixed. A study of healthy adults found that cognitive driving ability was impaired about 2 hours after taking trazodone, but that study used a 100 mg dose, double the 50 mg most insomnia patients take. At 25 mg, a separate study found no measurable impact on cognitive function after 9 days of use. At 50 mg specifically, one trial found that sleep quality improved but short-term memory showed small impairments after the first week of treatment. If you’re taking it for sleep, timing your dose about 30 minutes before bed gives the sedation its best chance to wear off by morning.
Blood Pressure Drops and Fall Risk
Trazodone can cause a noticeable drop in blood pressure when you stand up quickly, a phenomenon called orthostatic hypotension. In clinical trials, this affected 4 to 7% of users and led to fainting in 3 to 5%. You might feel it as a head rush, sudden dizziness, or momentary unsteadiness when getting out of bed or rising from a chair.
This effect is particularly relevant for older adults. A study of geriatric outpatients with high blood pressure found that trazodone users experienced greater drops in both systolic and diastolic blood pressure upon standing compared to non-users. More strikingly, the rate of fainting and falls was 58.3% among trazodone users versus 21.2% in the comparison group. Trazodone predicted falls independently of other risk factors. If you’re over 65, or if you take blood pressure medication, this is worth a conversation with your prescriber, and it’s worth being deliberate about standing up slowly, especially during nighttime bathroom trips.
Priapism: Rare but Serious for Men
Trazodone carries a well-known risk of priapism, a prolonged, often painful erection unrelated to sexual arousal. This happens in fewer than 1% of male users, but it’s a medical emergency when it does occur. The FDA label is clear: any erection lasting longer than 6 hours, whether painful or not, requires immediate emergency medical attention. Untreated priapism can cause permanent damage to erectile tissue.
Men with sickle cell anemia, certain blood cancers, or structural differences in the penis are at higher risk. Even though this side effect is uncommon, it’s the one that warrants awareness before you start the medication.
Serotonin Syndrome Risk With Other Medications
Trazodone increases serotonin activity in the brain, which is generally the point. But when combined with other drugs that also raise serotonin levels, the result can be a dangerous buildup called serotonin syndrome. Symptoms include agitation, rapid heart rate, high body temperature, muscle twitching, and in severe cases, seizures.
The combinations to be most careful about include MAO inhibitors (a class of older antidepressants that requires a two-week washout period before or after trazodone), lithium, the herbal supplement St. John’s wort, the amino acid tryptophan, certain migraine medications like sumatriptan, and pain medications like tramadol and fentanyl. If you take any medications that affect serotonin, including common antidepressants, your prescriber needs the full list.
The FDA Warning on Suicidal Thoughts
Trazodone carries the same boxed warning as all antidepressants: it may increase the risk of suicidal thoughts and behaviors in people under 25, particularly in the early weeks of treatment or after dose changes. This warning is based on short-term studies of antidepressants as a class, not trazodone specifically. It applies more to people taking higher doses for depression than to those using 50 mg for sleep, but the warning is on the label regardless of dose. New or worsening mood changes, especially in the first month, are worth reporting promptly.
What Happens When You Stop Taking It
Stopping trazodone abruptly, even at 50 mg, can trigger withdrawal-like symptoms. These may include rebound insomnia (your sleep getting temporarily worse than it was before you started), irritability, anxiety, and general discomfort. The risk increases with longer use. Tapering gradually, typically by reducing your dose in small steps over a few weeks, smooths out the transition and minimizes these effects. Even at a low dose, it’s worth stepping down rather than stopping cold.
When Side Effects Typically Ease
Most of the common side effects, particularly drowsiness, dizziness, and nausea, are strongest during the first week or two of treatment. Your body adjusts to the medication, and many people find that the initial grogginess and dry mouth become much more manageable after the adjustment period. Taking trazodone with a small snack can reduce nausea and may also slow absorption slightly, which can soften the initial wave of sedation. If side effects persist beyond the first few weeks or interfere with your daily functioning, that’s useful information for your prescriber to have when deciding whether to adjust the dose or try a different approach.