Based on NIH | If I’m taking sertraline for depression, what side effects should I expect, which ones are serious, and when should I seek medical help?

Sertraline side effects: what’s common, what’s serious, and when to get help

Starting sertraline (an SSRI) commonly brings mild, early side effects like nausea, diarrhea, trouble sleeping or sleepiness, dizziness, dry mouth, and sweating; these often ease within 1–2 weeks as your body adjusts. ^{[1] [2]} It can also cause headache, tremor/shakiness, stomach pain, anxiety or agitation, decreased appetite, and changes in sexual function such as lowered libido or difficulty with orgasm or ejaculation. ^{[1] [2]} Some people notice ringing in the ears, sore throat, or urinating more often, which are usually temporary. ^[1]

Serious side effects you should know about

• Serotonin syndrome: This is rare but urgent. Warning signs include agitation, hallucinations, fever, heavy sweating, confusion, fast heartbeat, shivering, severe muscle stiffness or twitching, loss of coordination, nausea, vomiting, or diarrhea. Get medical help right away if these occur. ^{[3] [2]}
• Abnormal bleeding: SSRIs can affect platelets and increase bleeding risk, especially if combined with NSAIDs (like ibuprofen/naproxen), aspirin, anticoagulants, or antiplatelet drugs. Watch for unusual bruising, nosebleeds, bleeding gums, black/tarry stools, or vomiting blood, and contact your clinician promptly. ^{[3] [4]}
• Seizures: Any seizure while on sertraline needs urgent care. ^[3]
• Severe skin reactions or allergy: Rash, hives, swelling of face/lips/tongue, or trouble breathing require immediate evaluation. ^[3]
• Hyponatremia (low sodium): Symptoms can include headache, weakness, unsteadiness, confusion, or memory problems; this is more likely in older adults or those on diuretics and needs prompt assessment. ^[3]
• Heart rhythm concerns: Fast heartbeat has been reported; if you feel pounding, very fast, or irregular heartbeat with dizziness or fainting, seek care. ^[1]

Mental health warnings and suicide risk

• A small number of people, especially younger adults, may experience new or worsening depression, anxiety, panic attacks, agitation, severe restlessness, irritability, acting without thinking, or thoughts about self‑harm when starting or changing the dose. If you notice these changes, contact your clinician urgently; if there is immediate danger, call emergency services. ^[5]

When to seek medical help

• Call emergency services now if you have symptoms of serotonin syndrome (see above), severe allergic reaction (trouble breathing, swelling), seizure, collapse, or if someone cannot be awakened. ^{[3] [6]}
• Seek urgent medical advice the same day for: unusual bleeding or bruising; severe or rapidly worsening agitation, confusion, or behavior changes; fever with muscle stiffness/shaking; very fast or irregular heartbeat; or signs of very low sodium like severe confusion or unsteadiness. ^{[3] [5]}
• Contact your prescriber within a day or two if common side effects are intense, persistent beyond 1–2 weeks, or interfere with daily life; dose timing, slower titration, or symptom‑relief strategies may help. ^[7]

How to lower your risk of side effects

• Start low and go slow: Doses are usually increased gradually, not more than weekly, to improve tolerability. ^[7]
• Take consistently: Sertraline can be taken with or without food; taking it at the same time daily often reduces stomach upset or sleep issues. If it causes insomnia, morning dosing may help; if it causes drowsiness, evening dosing may help. (General clinical practice)
• Avoid interacting medicines: Do not use sertraline with MAO inhibitors (such as phenelzine, tranylcypromine, selegiline), pimozide, or (for the oral liquid) disulfiram; dangerous interactions can occur. ^{[8] [9]}
• Be careful with serotonergic drugs: Combining with tramadol, fentanyl, triptans, lithium, St. John’s wort, tryptophan, linezolid, or methylene blue increases serotonin‑syndrome risk; always check with your clinician or pharmacist before adding anything new. ^{[10] [4]}
• Limit NSAIDs/aspirin unless advised: They raise bleeding risk when used with SSRIs; if you need pain relief, ask about safer options or whether a stomach‑protecting medicine is appropriate. ^[4]
• Alcohol: Minimizing alcohol can help avoid added sedation and reduce the chance of worsening depression. (General clinical advice)

Stopping sertraline safely

• Don’t stop suddenly unless your prescriber tells you to. Abrupt stopping can cause withdrawal‑like symptoms such as nausea, sweating, dizziness, anxiety, irritability, low mood, and “electric shock” sensations; a gradual taper is recommended to reduce this risk. ^{[7] [11]}

Expected timeline and what’s normal

• Many common side effects begin in the first few days and start to fade over 1–2 weeks as your body adjusts. ^{[1] [2]}
• The mood benefit may take a few weeks or longer; keep taking sertraline as directed even if you don’t feel better right away, and keep regular follow‑ups to fine‑tune the dose. ^[7]

Key interactions and contraindications (quick reference)

• Do not combine with: MAO inhibitors (isocarboxazid, phenelzine, tranylcypromine, selegiline), pimozide; do not use oral liquid with disulfiram. ^{[8] [9]}
• Use caution and consult your clinician before combining with: tramadol, fentanyl, triptans, lithium, linezolid, methylene blue, St. John’s wort, tryptophan, and many migraine or pain medicines due to serotonin‑syndrome risk. ^[10]
• Over‑the‑counter and herbal products: Always check labels and ask first; St. John’s wort and NSAIDs are notable concerns. ^[4]

Table: Common vs. serious side effects and actions

• Common, often temporary (1–2 weeks):

  • Nausea, diarrhea, dry mouth, sweating. Action: Continue if mild; take with food, stay hydrated; ask about dose timing if sleep is affected. ^{[1] [2]}
  • Dizziness, sleepiness or insomnia, headache, tremor, anxiety/agitation. Action: Monitor; adjust timing; discuss if persistent or severe. ^{[1] [2]}
  • Sexual side effects (low libido, delayed orgasm/ejaculation). Action: Discuss options if bothersome; dose adjustment or alternatives may help. ^[2]

• Serious seek urgent care:

  • Serotonin syndrome signs (agitation, fever, heavy sweating, fast heartbeat, shivering, muscle stiffness/twitching, confusion, severe nausea/diarrhea). Action: Emergency evaluation. ^{[3] [2]}
  • Unusual bleeding/bruising, black stools, vomiting blood. Action: Contact clinician promptly; may need medication changes. ^[3]
  • Seizure; severe allergic reaction (rash with swelling, trouble breathing). Action: Emergency care. ^[3]
  • Severe confusion, unsteadiness (possible low sodium). Action: Urgent assessment. ^[3]
  • Fast/irregular heartbeat with dizziness/fainting. Action: Emergency assessment. ^[1]

Overdose information

• Signs can include drowsiness, agitation, hallucinations, fever, sweating, confusion, fast heartbeat, tremors, severe muscle stiffness, loss of coordination, nausea, vomiting, diarrhea, severe tiredness, mania, seizures, loss of consciousness. Call poison control or emergency services immediately if overdose is suspected. ^[6]

Practical tips for day‑to‑day use

• Take at the same time daily, consider morning dosing if you feel wired at night, or evening dosing if it makes you drowsy. (General clinical practice)
• Manage nausea by taking with food and small, frequent meals; ginger tea or mints may help. (General clinical advice)
• For dry mouth, sip water, sugar‑free gum/lozenges, and good dental care. (General clinical advice)
• Keep a symptom diary for the first 2–4 weeks to track side effects and improvements; this helps guide dose adjustments. (General clinical advice)

The bottom line

• Most people experience mild side effects that improve within a couple of weeks, and many find sertraline effective for depression when taken consistently. ^{[1] [7]}
• Know the red‑flag symptoms especially serotonin syndrome, unusual bleeding, severe allergic reactions, seizures, and significant behavior changes and seek help promptly if they occur. ^{[3] [5]}

If you ever feel at immediate risk of harming yourself or others, or have severe symptoms like trouble breathing, seizures, or collapse, call emergency services right away. ^{[5] [6]}