Why antidepressant withdrawal happens
Antidepressants — particularly SSRIs and SNRIs — cause the brain to adapt over time. With prolonged use, the nervous system recalibrates itself around the presence of the medication. When the medication is reduced or stopped, the brain needs time to adjust back. The symptoms that arise during this process are withdrawal symptoms.
This is not addiction in the traditional sense, and it does not mean the person is weak or dependent in a character sense. It is a predictable physiological response to the removal of a substance the nervous system has adapted to. Around 50% of people who stop antidepressants experience withdrawal symptoms, and for 25–30% those symptoms are described as severe.
Physical withdrawal symptoms
Physical symptoms are among the most characteristic and diagnostically useful features of antidepressant withdrawal. They are particularly helpful in distinguishing withdrawal from relapse of the original condition.
- Brain zaps — brief, electric shock-like sensations in the head or body, often triggered by eye movement. Highly characteristic of antidepressant withdrawal and rarely seen in depression relapse
- Dizziness and vertigo — often severe, can make it difficult to function; particularly pronounced with short half-life drugs like venlafaxine
- Nausea and gastrointestinal upset — nausea, diarrhoea, stomach cramps; usually appear in the first days after a dose reduction
- Flu-like symptoms — sweating, chills, muscle aches, fatigue; often mistaken for a viral illness
- Sensory disturbances — heightened sensitivity to light, sound and touch; tingling or burning sensations; visual disturbances
- Tremor — fine muscle tremor, particularly in the hands
- Sleep disruption — vivid or disturbing dreams, insomnia, frequent waking; often one of the most persistent symptoms
- Headaches — typically diffuse; can be severe in the first week
Psychological and emotional withdrawal symptoms
Psychological symptoms are common and are frequently mistaken for relapse of the original condition. Understanding the difference is critical to managing the taper safely.
- Anxiety and agitation — can be intense and disproportionate to circumstances; reflects nervous system hyperexcitability during readjustment
- Irritability and mood instability — emotional reactivity that feels different from baseline; often described as feeling "raw"
- Low mood — frequently appears and is often interpreted as depression returning; see below for how to distinguish the two
- Depersonalisation and derealisation — feeling detached from oneself or one's surroundings; distressing but not dangerous
- Intrusive thoughts — unwanted thoughts that feel ego-dystonic (not reflective of the person's true beliefs or desires)
- Emotional flooding — sudden waves of emotion, crying spells, emotional lability
- Emotional blunting lifting — paradoxically, some people experience a return of emotional range as the medication reduces, which can feel overwhelming after years of dampened affect
Cognitive symptoms
- Brain fog — difficulty thinking clearly, mental slowing, word-finding difficulties
- Memory difficulties — short-term memory gaps, difficulty retaining new information
- Concentration problems — inability to focus, easily distracted
- Confusion — particularly in the early days after a reduction; usually transient
Symptoms most characteristic of withdrawal rather than relapse
- Brain zaps — almost never seen in depression relapse
- Dizziness and flu-like physical symptoms
- Symptoms beginning within days of a dose reduction
- Sensory hypersensitivity — to light, sound or touch
- Nausea in the absence of other illness
- Symptoms that improve when the dose is slightly increased or reinstated
Withdrawal versus relapse — how to tell the difference
This is the most clinically important question for anyone reducing antidepressants. Misidentifying withdrawal as relapse is one of the most common reasons antidepressants are reinstated unnecessarily.
| Feature | Withdrawal | Relapse |
|---|---|---|
| Onset after dose reduction | Days to a week | Weeks to months |
| Physical symptoms | Common and prominent | Rare |
| Brain zaps | Common | Absent |
| Resemblance to original illness | Often different, unfamiliar | Similar to original presentation |
| Response to reinstating dose | Rapid improvement (hours to days) | Slower improvement (weeks) |
| Course over time | Fluctuates, tends to improve with patience | Persists or worsens without treatment |
| Relationship to dose changes | Directly linked | Less directly linked |
Which antidepressants cause the worst withdrawal?
Withdrawal severity correlates primarily with the drug's half-life — how quickly it leaves the body — and with duration and dose of use. Drugs with shorter half-lives cause more rapid and intense withdrawal because the nervous system experiences sudden changes in drug levels.
- Venlafaxine (Efexor) — among the most difficult; half-life of approximately 5 hours; withdrawal can begin within hours of a missed dose
- Paroxetine (Seroxat) — well-documented severe withdrawal profile; short half-life; one of the most challenging SSRIs to stop
- Duloxetine (Cymbalta) — similar to venlafaxine; short half-life; intense physical symptoms
- Sertraline (Lustral) — moderate; manageable with careful tapering
- Citalopram / Escitalopram — moderate; longer half-life than paroxetine
- Fluoxetine (Prozac) — lowest withdrawal risk; very long half-life (weeks); effectively self-tapers
- Mirtazapine — significant sleep disruption on withdrawal; often underestimated
This is an educational resource
This page provides general information about antidepressant withdrawal. It does not replace individual clinical assessment. If you are experiencing severe or prolonged withdrawal symptoms, please seek medical advice. If you are in immediate distress, contact your GP or call 111.
Our approach
Getting the right support for withdrawal
Many people who come to us have been told their withdrawal symptoms are either not real, or are their original condition returning. We take a different view — withdrawal is a genuine physiological process that requires clinical understanding, not dismissal.
Our deprescribing support includes a clear framework for interpreting symptoms throughout the taper, adjusting the pace when withdrawal is significant, and distinguishing withdrawal from relapse at every stage.
Book an Initial ConsultationReferences
- 1. Davies J, Read J. A systematic review into the incidence, severity and duration of antidepressant withdrawal effects: are guidelines evidence-based? Addictive Behaviors. 2019;97:111–121. DOI: 10.1016/j.addbeh.2018.08.027
- 2. Fava GA, Gatti A, Belaise C, Guidi J, Offidani E. Withdrawal symptoms after selective serotonin reuptake inhibitor discontinuation: a systematic review. Psychotherapy and Psychosomatics. 2015;84(2):72–81. DOI: 10.1159/000370338
- 3. Horowitz MA, Taylor D. Tapering of SSRI treatment to mitigate withdrawal symptoms. Lancet Psychiatry. 2019;6(6):538–546. DOI: 10.1016/S2215-0366(19)30032-X
- 4. National Institute for Health and Care Excellence. Medicines associated with dependence or withdrawal symptoms. NICE guideline NG215. London: NICE; 2022.
- 5. Royal College of Psychiatrists. Stopping antidepressants. 2020. Available at: rcpsych.ac.uk
- 6. Horowitz MA, Taylor D. The Maudsley Deprescribing Guidelines. Wiley-Blackwell; 2024. ISBN: 978-1119822981
Related reading
Antidepressant withdrawal symptoms are real, they are common, and they are manageable with the right approach.
The most important thing is not to mistake them for something else — and not to go through them without proper clinical support.