Important: This is informational content only. Always consult Dr. Ambrish Singal or your psychiatrist before starting, stopping, or changing any medication.
What is Paroxetine?
Paroxetine is a potent SSRI with additional mild anticholinergic properties. It is effective for depression, anxiety disorders, and is particularly used for social anxiety and panic disorder.
How It Works
Inhibits serotonin reuptake with high potency. Also has mild norepinephrine reuptake inhibition and anticholinergic effects, which can contribute to both therapeutic and side effects.
Uses
How This Drug Starts Working
Takes 2-4 weeks for initial benefit, 4-6 weeks for full effect. Anxiety symptoms often improve before mood.
Week-by-Week Timeline
Week 1: May feel slightly more sedated. Some initial nausea. Sleep may improve (sedating properties).
Week 2: Anxiety and panic symptoms often start to reduce. Appetite may increase.
Week 3-4: Mood improving. Social anxiety reducing. Concentration better.
Week 5-6: Full effect. Significant improvement across all symptoms.
What Changes First?
Sedation and reduced anxiety appear first (days to 1 week). Sleep improvement early. Mood and motivation follow later (3-6 weeks).
Why Does It Take Time?
Same serotonin receptor remodeling as other SSRIs, plus paroxetine's mild anticholinergic effects provide early sedation/anxiolysis while the deeper antidepressant changes develop.
Complete Dosage Guide
How to Take
Take once daily in the MORNING with food (improves absorption, reduces nausea). Swallow whole — do not crush controlled-release tablets.
Starting Dose
20mg daily (depression, GAD). 10mg daily (panic disorder — to avoid initial anxiety spike). 20mg (social anxiety, OCD).
Dose Increases
Increase by 10mg every 1-2 weeks if needed. Wait at least 2 weeks between increases.
Maximum Dose
Depression: 50mg. Panic: 60mg. OCD: 60mg. Social anxiety: 60mg.
When to Take
Morning dosing preferred. Slightly sedating for most people. Take at the same time daily — paroxetine's short half-life means consistent dosing matters more than with fluoxetine.
If You Miss a Dose
Take as soon as remembered BUT never late evening (insomnia). If close to next dose, skip. IMPORTANT: Even one missed dose can cause withdrawal symptoms (brain zaps, dizziness) due to short half-life.
Food & Drink
Take with food to improve absorption and reduce stomach upset.
How Long to Take
Long-term use common. If discontinuing: MUST taper very slowly over weeks to months (most difficult SSRI to stop).
Dosage by Age Group
adult
Depression: 20mg/day, may increase to 50mg. Panic: Start 10mg, increase to 40mg. OCD: 20-60mg/day.
child
Not recommended for children under 18 due to increased suicidality risk.
elderly
Start 10mg/day. Maximum 40mg/day.
Special Populations
Pregnancy
Category D - AVOID in pregnancy. Associated with cardiac birth defects in first trimester.
Kidney Conditions
Reduce dose in severe renal impairment.
Liver Conditions
Use lower doses. Plasma levels increase in hepatic dysfunction.
Side Effects
Common
- Sedation
- Weight gain
- Sexual dysfunction
- Dry mouth
- Constipation
- Nausea
- Sweating
Serious
- Discontinuation syndrome (most severe among SSRIs)
- Suicidal thoughts in youth
- Serotonin syndrome
- Birth defects if used in first trimester
What You Should Know
Overdose Risks
Generally less dangerous than TCAs in overdose. May cause drowsiness, nausea, tremor, and in severe cases, serotonin syndrome.
Safe Discontinuation
MUST taper very gradually over 4-8 weeks. Paroxetine has the highest rate of discontinuation syndrome among SSRIs due to its short half-life. Symptoms: electric shock sensations, dizziness, nausea, anxiety.