Mirtazapine Withdrawal & Tapering Guide
mirtazapine
Boxed Warning
Suicidality risk in children, adolescents, and young adults under 25 during initial treatment.
In short
Mirtazapine (mirtazapine) is a NaSSA with a half-life of 20–40 hours. Rebound insomnia is very common at lower doses due to stronger antihistamine effect. It is also sold as Remeron, Avanza, Zispin.
- Class
- NaSSA
- Half-life
- 20–40 hours
- Common doses
- 7.5mg, 15mg, 30mg, 45mg
Educational reference only. Dose changes are decided with the prescriber who knows your history.
Overview
Mirtazapine is a noradrenergic and specific serotonergic antidepressant (NaSSA) approved for major depressive disorder. It has a unique mechanism that does not involve reuptake inhibition. It is known for sedation and appetite stimulation, especially at lower doses.
7.5mg, 15mg, 30mg, 45mg
Tablets: 7.5mg, 15mg, 30mg, 45mg; Orally disintegrating tablets (SolTab): 15mg, 30mg, 45mg
Category C (risk cannot be ruled out)
Mechanism of Action
Antagonist at central alpha-2 adrenergic autoreceptors and heteroreceptors, increasing noradrenergic and serotonergic neurotransmission. Also antagonizes 5-HT2A, 5-HT2C, 5-HT3, and histamine H1 receptors. The strong H1 antagonism causes sedation and weight gain.
Taper Notes
Rebound insomnia is very common at lower doses due to stronger antihistamine effect. Paradoxically more sedating at lower doses.
Hyperbolic Tapering Guidance
Tablet can be split or dissolved in water for precise dosing. Rebound insomnia at lower doses often mistaken for relapse — distinguish withdrawal from relapse by timing.
Summary written by TaperCommunity, informed by the Maudsley Deprescribing Guidelines (Horowitz & Taylor) and related literature — see Sources & References below. Not affiliated with or endorsed by the Maudsley.
Common Withdrawal Symptoms
Interactions & Safety
Drug Interactions
- MAOIs — contraindicated (serotonin syndrome risk)
- Serotonergic drugs increase serotonin syndrome risk
- CYP3A4 inhibitors (ketoconazole) may increase mirtazapine levels
Food Interactions
- Food has minimal effect on absorption
- Avoid alcohol (additive CNS depression)
Contraindications
- MAOIs within 14 days
- Known hypersensitivity to mirtazapine
Toxicity
Relatively low toxicity in overdose compared to TCAs. Agranulocytosis/neutropenia rarely reported. Weight gain and metabolic effects. Serotonin syndrome possible with serotonergic combinations.
Pharmacokinetics
ADME Profile
Rapidly and completely absorbed. Bioavailability ~50%. Tmax ~2 hours. Food has minimal effect on absorption.
~4.5 L/kg
Extensively metabolized hepatically via CYP2D6, CYP3A4, and CYP1A2 to demethyl and hydroxylated metabolites, which have minimal pharmacological activity.
Renal (~75%) and fecal (~15%). Less than 5% excreted unchanged in urine.
~85%
~230 mL/min (apparent oral clearance)
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Other Drug Profiles
The arithmetic of a proportional reduction
The Maudsley Deprescribing Guidelines and NICE NG222 describe reducing NaSSA medications by a proportion of the previous dose rather than by a fixed amount, so each cut is smaller than the last. The table shows what that arithmetic produces at 10% per step, using 15 mg only as a worked example. How large each step is, how long it is held, and whether this pattern applies at all are decisions for the person and their prescriber.
| Step | % of starting dose | Worked example (15 mg start) |
|---|---|---|
| Start | 100% | 15 mg |
| Step 1 | 90% | 13.5 mg |
| Step 2 | 81% | 12.2 mg |
| Step 3 | 73% | 10.9 mg |
| Step 4 | 66% | 9.84 mg |
| Step 5 | 59% | 8.86 mg |
| Step 6 | 53% | 7.97 mg |
| Step 7 | 48% | 7.17 mg |
| Step 8 | 43% | 6.46 mg |
This is an illustration of a published method, not a schedule for anyone. It does not account for how long you have taken Mirtazapine, your current dose, formulation, or history. TaperCommunity does not recommend doses or dose changes; those are agreed with your prescriber.
Frequently asked questions about Mirtazapine
What are the withdrawal symptoms of Mirtazapine (mirtazapine)?
Common withdrawal symptoms of Mirtazapine (mirtazapine) include: rebound insomnia, anxiety, nausea, headache, irritability, appetite changes. Symptom severity varies by individual, dose, and duration of use.
How should I taper off Mirtazapine (mirtazapine)?
Rebound insomnia is very common at lower doses due to stronger antihistamine effect. Paradoxically more sedating at lower doses. Tablet can be split or dissolved in water for precise dosing. Rebound insomnia at lower doses often mistaken for relapse — distinguish withdrawal from relapse by timing.
Can I stop Mirtazapine cold turkey?
Stopping Mirtazapine abruptly is not recommended. Its half-life is 20–40 hours, and the receptor adaptations built up during treatment do not reverse at that speed, so a sudden stop tends to produce the sharpest withdrawal. Prescribing guidance favours gradual, proportional reductions agreed with your prescriber.
How long does Mirtazapine stay in your system?
Mirtazapine (mirtazapine) has a half-life of 20–40 hours. A drug is mostly cleared after about five half-lives, so Mirtazapine is largely out of the body roughly 4 to 8 days after the last dose, longer in older adults or with liver or kidney impairment. Withdrawal symptoms often begin before the drug has fully cleared and continue after it has, because the adaptations the brain made during treatment reverse more slowly than the drug leaves the blood.
Recent discussions about Mirtazapine
What members tapering Mirtazapine are asking and reporting right now. Personal experience, not medical advice.
- Mirtazepine Tapering ThreadThis is the forum for everyone tapering Mirtazepine. When you log a check-in in My Taper, it will appear here. That way you can see how others on the same medication are…Based · 8 months ago
- How to taper several drugs?Is there a consensus on how to taper when your on multiple drugs? Assuming that I taper one at a time do you: (a) Taper until fully off one then over to the next (b)…Vic247 · 4 days ago · 4 replies
- Why do we taper?This might sound like a silly question, since the obvious answer is to get off these chemical stuff that most of us started taking with little to no informed consent.…Vic247 · 4 days ago · 18 replies
- I started on 8/21 from 300mgI’ve now been on 7.5 for several weeks. My question is— Is the night usually the worst time for folks? It is for me. I eat, not hungry, stomach is upset, but I eat bland…Katestthelake · 5 days ago · 11 replies
- Want to hear from folks about Mirtzapine taperingI would love to hear anything that anyone has to say about tapering from this drug. I’m 3 weeks in and started at 30mg and am tapering at 25% every four weeks. At least…Katestthelake · 7 days ago · 16 replies
Sources & References
Mirtazapine (mirtazapine) information on this page is sourced from peer-reviewed research, regulatory bodies, clinical guidelines, and patient-advocacy organizations.
Encyclopedic & chemical databases
Neutral, high-authority entity references.
Peer-reviewed research
Primary literature cited in this taper guide.
- Horowitz MA, Taylor D 2019 — Tapering of SSRI treatment to mitigate withdrawal symptoms (hyperbolic taper) (The Lancet Psychiatry)
- Davies J, Read J 2019 — A systematic review into the incidence, severity and duration of antidepressant withdrawal effects (Addictive Behaviors)
- Framer A 2021 — The patient voice: an exploration of the experience of withdrawal from antidepressants (Therapeutic Advances in Psychopharmacology)
Clinical guidelines
Evidence-based deprescribing and prescribing standards.
Deprescribing-specific resources
Clinician-facing references on tapering protocols.
- Deprescribing.org — Evidence-based deprescribing algorithms from the Bruyère Research Institute
- Royal College of Psychiatrists — Stopping antidepressants — UK clinical guidance on safely discontinuing antidepressants
Patient-advocacy & lived-experience
Long-running communities documenting withdrawal experience.
- Surviving Antidepressants — tapering forum — Long-running community archive of antidepressant taper experiences
- Inner Compass Initiative — Withdrawal Project — Peer-led resources for psychiatric drug withdrawal
- Mad in America — antidepressant withdrawal archive — Journalism and personal narratives on SSRI/SNRI discontinuation
- RxISK — adverse drug reaction reporting — Independent database of patient-reported adverse effects
TaperCommunity does not provide medical advice. Always consult a qualified prescriber before adjusting psychiatric medication.