Trazodone Side Effects: What to Know About This Sleep Medication

Trazodone is one of the most frequently prescribed medications for insomnia in the United States, yet many patients start taking it without a clear picture of what to expect. Understanding trazodone side effects before you fill that prescription can help you tell normal adjustment symptoms apart from reactions that need medical attention. Originally developed as an antidepressant, trazodone is now used off-label for sleep at doses lower than those used for depression — and its side-effect profile shifts accordingly. Trazodone is a prescription-only medication, and everything below is general education, not medical advice; your prescriber’s guidance always comes first.

How Trazodone Works and Why Side Effects Occur

Trazodone belongs to a class called serotonin antagonist and reuptake inhibitors (SARIs). It blocks certain serotonin receptors while also inhibiting serotonin reuptake, which produces both its antidepressant and its sedative effects. At the lower doses typically used for sleep, the sedating properties tend to dominate, which is why clinicians commonly reach for it in insomnia. At the higher doses used to treat depression, the antidepressant effects become more prominent. The exact dose and schedule are decisions for your prescriber, not something to adjust on your own.

Side effects occur because serotonin activity influences many body systems beyond mood and sleep — including blood-pressure regulation, digestive function, and sexual response. According to the FDA prescribing information and MedlinePlus, many side effects are related to dose and tend to diminish within the first few weeks of use as the body adjusts.

Common Trazodone Side Effects

The most frequently reported trazodone side effects are generally mild and often improve over time. Commonly described reactions include:

• Drowsiness and sedation — the most common complaint; it is both the desired effect for insomnia and a frequent source of next-day grogginess
• Dizziness or lightheadedness — especially when standing up quickly
• Dry mouth — a common anticholinergic-type effect
• Headache
• Nausea or upset stomach — often eased by taking the medication with a small amount of food
• Blurred vision
• Constipation
• Fatigue or feeling “washed out” during the day

Most of these effects are strongest during the first week and tend to taper as your body adjusts. Taking trazodone with a small snack may reduce nausea. If a common side effect is bothersome or lingers, your prescriber can talk through options rather than you stopping the medication on your own.

Next-Day Drowsiness

Perhaps the most troublesome common side effect is residual sedation the morning after a dose — a “hangover” feeling that can linger. How much it affects you depends on your individual response, the dose your prescriber has set, and timing. If morning drowsiness persists beyond the first couple of weeks, your doctor may reconsider the timing, the dose, or an alternative. Driving or operating heavy machinery while you feel this way poses a real safety risk, so avoid both until you know how the medication affects you.

Serious Side Effects That Need Medical Attention

While uncommon, certain trazodone side effects require prompt medical evaluation — and a few are true emergencies. Learn to recognize them.

Priapism — A Medical Emergency

One of trazodone’s most well-known rare side effects is priapism — a prolonged, often painful erection that does not go away. An erection lasting more than four hours is a medical emergency. Seek immediate care right away, because delay can lead to permanent damage to erectile tissue. This is rare, but it is the single most important warning to understand before taking trazodone. Do not wait to “see if it resolves.”

Serotonin Syndrome

Combining trazodone with other serotonergic medications can trigger serotonin syndrome, a potentially life-threatening condition. Warning signs include agitation or confusion, high fever, a rapid heartbeat, muscle rigidity or twitching, heavy sweating, shivering, and tremor. This risk rises when trazodone is used alongside SSRIs, SNRIs, MAOIs, or certain migraine medications such as triptans. Serotonin syndrome can escalate quickly — if you notice this cluster of symptoms, treat it as an emergency and call 911.

Orthostatic Hypotension and Falls

Trazodone can cause a drop in blood pressure when you move from sitting or lying down to standing, leading to dizziness, fainting, or falls. Older adults are particularly vulnerable. The Mayo Clinic suggests rising slowly from a bed or chair and staying hydrated to reduce this risk.

Cardiac Rhythm Changes

Trazodone can prolong the QT interval on an electrocardiogram, which in rare cases contributes to dangerous heart-rhythm changes. People with pre-existing heart conditions, electrolyte imbalances, or those taking other QT-prolonging medications may face higher risk. The FDA has flagged this concern in the drug’s labeling.

When to seek emergency care: Call 911 or go to the nearest emergency room for an erection lasting longer than four hours, symptoms of serotonin syndrome, fainting, an irregular or pounding heartbeat, seizures, or signs of a severe allergic reaction such as swelling of the face, lips, tongue, or throat, or trouble breathing. If someone takes far more trazodone than prescribed, contact Poison Control at 1-800-222-1222 (free and confidential, 24/7) and call 911 for a medical emergency.

Trazodone, Antidepressants, and Suicide Risk

Like all antidepressants, trazodone carries an FDA boxed warning about an increased risk of suicidal thoughts and behavior in children, adolescents, and young adults under 25. This risk is most pronounced during the first few months of treatment or when the dose changes. Family members and caregivers should watch for unusual mood shifts, agitation, worsening depression, or withdrawal, and stay in close contact with the prescriber.

If you or someone you know is having thoughts of suicide or self-harm, call or text 988 to reach the 988 Suicide and Crisis Lifeline, available 24/7, or go to the nearest emergency room. Some patients report increased anxiety or restlessness when starting an antidepressant; these symptoms often settle within a week or two, but if they worsen or feel unmanageable, contact your prescriber rather than stopping the medication abruptly. For more on medication-related mental-health concerns, see our medical conditions guide.

Drug Interactions to Watch

Trazodone interacts with a wide range of medications, which makes it essential to share your complete medication and supplement list with your doctor and pharmacist.

• MAO inhibitors — combining trazodone with MAOIs (such as phenelzine or tranylcypromine) is contraindicated because of the severe risk of serotonin syndrome
• SSRIs and SNRIs — fluoxetine (Prozac), sertraline (Zoloft), and duloxetine (Cymbalta) can raise serotonin syndrome risk when used with trazodone
• Certain migraine medications — triptans also add to serotonergic load
• CYP3A4 inhibitors — ketoconazole, ritonavir, and clarithromycin can raise trazodone blood levels and intensify side effects
• Blood-pressure medications — combining trazodone with antihypertensives such as losartan or metoprolol may add to blood-pressure lowering
• Alcohol and benzodiazepines — both amplify sedation and the risk of slowed breathing
• Warfarin — trazodone may change warfarin’s blood-thinning effect, so INR monitoring may be advised

The MedlinePlus drug information library and your pharmacist can help check specific combinations before you start a new medication.

Side Effects in Older Adults

Trazodone is frequently prescribed to older adults for insomnia, but this group faces amplified risks. Older bodies often clear trazodone more slowly, which can mean stronger or longer-lasting sedation. Falls are a major concern — the combination of drowsiness, dizziness, and orthostatic hypotension can make nighttime bathroom trips hazardous.

Guidance from the National Institute on Aging and sleep specialists generally favors non-drug approaches to insomnia — especially cognitive behavioral therapy for insomnia (CBT-I) — as first-line treatment in older adults. When trazodone is used in this group, prescribers typically begin cautiously and reassess often; the specific dose is theirs to set.

Stopping Trazodone Safely

Never stop trazodone abruptly on your own. Discontinuation can cause withdrawal-like symptoms including rebound insomnia, irritability, anxiety, and nausea. If you and your prescriber decide to stop, they will usually guide a gradual reduction on a schedule tailored to you rather than a sudden halt. If you are having troublesome side effects, your doctor may suggest alternatives such as Wellbutrin for depression or a different sleep strategy — but that is a conversation to have before making any change.

When to Call Your Doctor

Not every side effect is an emergency, but several signs should prompt a call to your healthcare provider, generally within a day:

• Persistent dizziness or fainting episodes
• New or worsening mood changes, increased anxiety, or feelings of hopelessness
• Unusual bruising or bleeding
• Vision changes that do not resolve quickly
• Severe headache or confusion
• Skin rash or hives
• Side effects that persist beyond the first few weeks or interfere with daily life

Frequently Asked Questions

Does trazodone cause weight gain?

Significant weight gain is not among the most commonly reported trazodone side effects, unlike some other antidepressants. Some people notice a modest appetite change. At the lower doses used for sleep, weight effects appear to be less likely, though individual responses vary.

How long do trazodone side effects last?

Most common effects such as drowsiness, dry mouth, and dizziness tend to improve within the first one to two weeks as the body adjusts. If side effects persist beyond a few weeks or worsen over time, talk with your prescriber about next steps.

Can I drink alcohol while taking trazodone?

Alcohol significantly increases trazodone’s sedating effects and can add to drops in blood pressure. Prescribing guidance strongly advises against combining the two. Even small amounts of alcohol can amplify drowsiness and impair judgment and coordination.

Is trazodone addictive?

Trazodone is not considered habit-forming and is not a controlled substance, unlike some sleep and anti-anxiety medications such as Xanax or zolpidem. However, the body can adjust to it over time, so stopping suddenly may cause withdrawal-like symptoms. A prescriber-guided taper is the safe approach.

Does trazodone affect sexual function?

Sexual side effects appear to occur less often with trazodone than with SSRIs, but some people report reduced libido or difficulty with arousal. The rare but serious risk of priapism in men — an erection lasting more than four hours — is the most important sexual side effect to know about, and it requires emergency care. Report any unusual sexual changes to your doctor.

Is trazodone safe during pregnancy or breastfeeding?

There is no simple yes-or-no answer, and older FDA pregnancy letter categories (A, B, C, D, X) have been retired in favor of narrative labeling. If you are pregnant, planning pregnancy, or breastfeeding, this is a decision to make with your prescriber, who can weigh your specific situation against the risks of untreated symptoms.

The Bottom Line

Trazodone remains a commonly prescribed sleep aid partly because its side-effect profile is generally milder than that of alternatives such as benzodiazepines. Drowsiness, dizziness, and dry mouth top the list of common complaints, while serious reactions — priapism, serotonin syndrome, and cardiac rhythm changes — are rare but demand immediate attention. Taking the medication as prescribed, rising slowly from bed, and avoiding alcohol can minimize many common trazodone side effects. Stay in close contact with your prescriber, especially during the first month, and never hesitate to report symptoms that feel unusual or concerning.

Sources

• MedlinePlus (NIH/U.S. National Library of Medicine) — Trazodone
• U.S. Food and Drug Administration / DailyMed — Trazodone prescribing information (boxed warning; priapism; serotonin syndrome)
• Mayo Clinic — Trazodone (oral route): side effects, precautions
• 988 Suicide and Crisis Lifeline (SAMHSA)
• Poison Control — Poison Help, 1-800-222-1222