Trazodone Side Effects | Possible Side Effects of Trazodone

Introduction to Trazodone Side Effects

When you constantly feel sad and lose interest, you may suffer from depression. This serious mood disorder affects the feelings, thinking, and acting of one in 15 adults in the U.S. every year. (1) Long-term treatment with trazodone or other antidepressants mostly help, but is there any risk for side effects?

Trazodone may slow your thinking and motor skills. If it happens to you, you can avoid driving a car or operating dangerous machinery easily until you find out how trazodone works. On the other hand, high fever, tremors, seizures, and irregular heartbeat can be signs of serotonin syndrome, a life-threatening condition requiring immediate medical help. (2)

Keep reading and find all you need to know about these and other common and serious symptoms. Learn to recognize the signs of urgent situations and when to call a doctor. Some require immediate medical help and will save your life.

Common Trazodone Side Effects

The common side effects of trazodone occurring in >5% of the trazodone-treated patients and greater than the rate of the placebo group are:

Trazodone side effects

Trazodone side effects – The common side effects

  • Drowsiness – 41%;
  • Dry mouth – 34%;
  • Dizziness/light-headedness – 28%;
  • Headache – 20%;
  • Blurred vision – 15%;
  • Nausea/vomiting – 13%;
  • Constipation – 8%;
  • Skin condition/edema – 7%;
  • Stuffy nose – 6%;
  • Weight loss – 6%;
  • Diarrhea – 5%. (2)

The frequency shown above relies on the outpatients’ reports in clinical trials. Some common side effects will improve as your body gets used to this medication. Keep reading to learn about serious possible side effects, warnings, and precautions when using trazodone.

Warnings and precautions when you take trazodone

Trazodone is prescribed to treat a major depressive disorder in adults only. Those who use monoamine oxidase inhibitors, the first generation of antidepressants, antibiotic linezolid, or intravenous methylene blue should not take trazodone together. (2)

Trazodone can interact with certain prescription medications (migraine medication, nonsteroidal anti-inflammatory drugs, diuretics, aspirin), out-of-counter medications, or herbal products. Tell your doctor about your current treatment; some require treatment discontinuation. (2)

Serious side effects that trazodone can cause are:

Suicidal thoughts

When start using SSRI antidepressants, such as trazodone, the most important to know is that these medicines may increase suicidal thoughts or behaviors in young adults, teenagers, and children. (2)

An analysis of placebo-controlled trials where about 77,000 adults and 4,400 children used antidepressant drugs showed that the risk of suicide in the treatment group was greater than in the placebo group. This conclusion comes from short-term studies. (2-3)

It is not known whether there is a risk in long-term use. The clinical evidence of maintenance trials in adults with major depressive disorder shows that antidepressants delay the recurrence of depression.  (2)

Depression and other mental illnesses may, by themselves, be causes of suicidal thoughts and doing so. People who had in their family manic-depressive illness or someone with suicidal thoughts and behavior are at higher risk. (2)

If you are new to antidepressants, pay attention to the following symptoms:

  • Depression that is new or getting worse;
  • Anxiety, new or worsened;
  • Irritability, new or worsened;
  • Thoughts about suicide or dying;
  • Attempts to commit suicide;
  • Panic attacks;
  • Aggressive behavior, anger, or being violent;
  • Other unusual changes in mood or behavior. (2-3)

Call your doctor if you notice any symptoms or changes in thoughts and feelings. Also, tell your loved ones that you have started using trazodone. They can also detect any change in your mood and behavior and help you.

Serotonin Syndrome

Serotonin syndrome is a serious side effect where the serotonin level is increased and may occur when using trazodone alone. Using it together with other serotonergic agents (e.g., SSRI, SNRI, triptans) increases the risk. (2)

Trazodone is a serotonin modulator. It increases the serotonin level, a neurotransmitter and so-called hormone of happiness, and helps maintain mental balance. (3) Our body produces serotonin which is responsible for our mood, memory, body temperature, sleep, and hunger. When its level is lower, it may cause depression, anxiety, or mania. (4)

On the other hand, too much serotonin may cause mild to severe symptoms. Symptoms may occur as early as several hours after starting the therapy or when the dose is increased. Some of the symptoms of serotonin syndrome are:

  • Agitation or restlessness;
  • Insomnia;
  • Confusion;
  • Dilated pupils;
  • Rapid heart rate;
  • High blood pressure;
  • Muscle rigidity;
  • Loss of muscle coordination or twitching muscles;
  • Heavy sweating;
  • Diarrhea;
  • Shivering. (2, 4)

Severe serotonin syndrome needs medical treatment, otherwise can cause death. The signs of severe serotonin are:

  • High fever;
  • Tremor;
  • Seizures;
  • Irregular heartbeat;
  • Unconsciousness. (2, 4)

If you recognize any symptoms, stop taking trazodone and call your doctor immediately for supportive medical treatment.

Priapism and other reproductive system-related side effects

Be aware that trazodone, among other side effects, may cause sexual problems. Men and women may experience decreased sex drive. Delayed orgasm or not having an orgasm can be a side effect in women. (2-3)

In men who take trazodone, a prolonged and uncontrolled erection named priapism may occur. Priapism can be painful. (2)

The blood, as with other organs, delivers oxygen to the penis. If the erection lasts too long, the blood is trapped in the penis, and the tissues cannot get oxygen. This affects functionality as well as can damage or destroy tissue. Priapism can also affect erection and lead to erectile dysfunction. (5)

Four-hour or longer erection can signify prolonged penile erections or priapism. It requires immediate medical treatment to prevent another episode and tissue damage. Call your doctor if you experience a long-lasting erection, even if it goes away. (2, 5)

Irregular or fast heartbeat and fainting (2)

Irregular heartbeat (heart arrhythmia) happens when the signals responsible for the heart’s beat don’t work properly. If the heartbeat is fast, it is called tachycardia. Those who experience a fast heartbeat feel fluttered. Shortness of breath, chest pain, anxiety, fatigue, lightheadedness, or dizziness are other irregular heartbeat symptoms that require immediate medical help. (6)

Fainting (syncope) is a few seconds or minutes when you lose consciousness. It happens when the blood flow in the brain decreases. You may feel cold, dizzy, lightheaded, hot, and suddenly sweaty, or stressed out or anxious before it happens.

If it happens, when you wake up, sit or lie down for 10-15 minutes, check if you have any injuries, sit forward and lower the head below your shoulders and knees, and take ice or cold water. (7)

Increased Risk of Bleeding

Trazodone treatment may increase the risk of bleeding when used with aspirin, warfarin, nonsteroidal anti-inflammatory drugs (NSAIDs), antiplatelet drugs, and other anticoagulants. The bleeding may occur in the gastrointestinal tract. (2)

Dark purple bruises, hematomas, nose bleeding, and red, purple, or brown round dots on the skin (petechiae) are other signs of a bleeding event. Bleeding from a damaged blood vessel is called hemorrhage. In some cases, such as bleeding in the brain, hemorrhage may be serious and life-threatening. (2, 8) If you have bleeding in the brain, you may have headaches or trouble breathing.

If you have nausea, dizziness, tiredness, or weakness, these can be symptoms of serious blood loss. In that case, seek immediate medical care. (2, 8)

Discontinuation syndrome

The recommendation to end trazodone treatment is to go slowly with graduate dose reduction. It is because an abrupt interruption can cause a discontinuation syndrome followed by nausea, sweating, irritability, tremor, anxiety, confusion, headache, lethargy, insomnia, hypomania, tinnitus, and seizures. (2-3)

Follow the dosage regime as your doctor prescribed, and consult when you experience adverse reactions if you need to stop taking trazodone.

These are some of the possible side effects. For the complete list of side effects, read the Patient Information (Medication Guide) carefully.


The recommended daily dose to start trazodone treatment is 150 mg. Take trazodone in divided doses per the doctor’s recommendation after a meal or snack. The dose increase goes slowly, 50 mg daily every three to four days, up to the maximal 400 mg/day. (2)

After treatment response is achieved, reduce the dosage gradually, as per the doctor’s recommendation.

Tell your doctor if you experience drowsiness; dose reduction or taking most of the daily dose before bedtime can be a solution.

Final Takeaways

Trazodone is an over-40-year-old antidepressant that can help in depression treatment. Its efficacy and safety profile are well-known. Its usage as prescribed by the doctor will help you to achieve symptom improvement without putting you at risk of overdose or discontinuation syndrome.

Be aware of the possible side effects and their symptoms to know when to call a doctor. Ask your doctor about possible side effects and call your doctor if you experience some. You can report adverse events to your doctor or send a report to the Food and Drug Administration’s (FDA) MedWatch Adverse Event Reporting program online ( or by phone (1-800-332-1088).

Every medication usage brings the risk of side effects, and so does trazodone. Speak with your doctor about other changes in your life that can help in depression treatment. For example, a healthy diet and physical activity can boost your serotonin level and improve your condition, together with medication.

Do your best in the overall treatment approach and make yourself feel good and happy again.

See Also

Atorvastatin Side Effects

Metformin Side Effects

Prednisolone Side Effects

Side Effects of Paxlovid

Gabapentin Side Effects

Cephalexin Side Effects

Ibuprofen Side Effects

1. American Psychiatric Association, What is Depression? 2020 Oct,

2. Food and Drug Administration, DESYREL® (trazodone hydrochloride) tablets, for oral use, 2017 Jun,

3. MedlinePlus, Trazodone, 2022 Jan,

4. Cleveland Clinic, Serotonin, 2022 Mar,

5. Urology Care Foundation, What is Priapism?, 2022 Aug,

6. Mayo Clinic, Heart Arrhythmia, 2022 Apr,

7. Cleveland Clinic, Fainting, 2021 Aug,

8. Cleveland clinic, Hemorrhage, 2021 Jul,


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