If you’re starting or changing an antidepressant, it’s normal to worry about side effects. You’re not alone — many people experience temporary symptoms that improve with time or simple adjustments.

1. What are the most common side effects?

Short answer: the most frequent effects are nausea, headache, fatigue or drowsiness, insomnia or agitation, sexual difficulties, dry mouth, sweating, dizziness, and weight changes. Different drug classes (SSRIs, SNRIs, TCAs) vary, but these are the typical complaints.

2. How long do these side effects usually last?

Short answer: many side effects improve within a few days to a few weeks. Nausea, headache, lightheadedness and sleep changes often ease in 1–4 weeks. Fatigue or sleep problems may shift within the first month. Weight change and sexual side effects can take weeks to months and sometimes persist longer. If symptoms are severe or continue beyond about 6–8 weeks, talk with your prescriber.

3. When should I contact my doctor or seek urgent care?

Short answer: contact a clinician right away for any severe, sudden, or dangerous symptoms — including suicidal thoughts, severe chest pain, high fever, very fast heartbeat, severe rash, signs of bleeding, or signs of serotonin syndrome (confusion, high temperature, tremor, sweating, stiff muscles). If in immediate danger, call emergency services.

4. Can side effects be managed without stopping treatment?

Short answer: often yes. Common strategies include dose adjustments, changing the time of day you take the medication, switching to a different antidepressant, or adding short-term treatments for specific symptoms. Non-medical strategies (sleep hygiene, relaxation, therapy) also help. For help with anxiety-related symptoms, see our guide on How to stop worrying, and for broader coping techniques review depression and anxiety: early signs and coping strategies.

5. What is the first step if I’m worried about side effects?

First step: don’t stop the medication suddenly. Contact the prescriber (doctor, psychiatrist, or pharmacist) to report symptoms and ask whether to change dose, timing, or medication. If you’re feeling very distressed or having suicidal thoughts, seek immediate help or call a crisis line.

Quick summary

• Common effects: nausea, headache, sleep changes, fatigue, sexual changes, dry mouth, sweating, dizziness.
• Typical timeline: many side effects improve in 1–4 weeks; some take weeks–months.
• When to act: contact a clinician for severe symptoms or if problems persist beyond 6–8 weeks.
• Management: dose changes, switching meds, timing adjustments, or supportive therapies can help.
• Immediate danger: seek emergency care for suicidal thoughts, severe allergic reactions, or signs of serotonin syndrome.

You deserve care that reduces suffering without judgment. If you want individualized support, contact your prescriber or a mental health professional — and remember that asking for help is a strong and important step.

Related reading: Common mental disorders and how they affect daily life.