What is antidepressant withdrawal?

Antidepressant withdrawal

Antidepressant withdrawal (sometimes called “discontinuation syndrome”) refers to the cluster of physical and psychological symptoms that can occur when a person reduces the dose of, or stops, an antidepressant—most commonly selective-serotonin re-uptake inhibitors (SSRIs) or serotonin–noradrenaline re-uptake inhibitors (SNRIs). Symptoms may emerge within a few days of dose reduction, peak during the first two weeks, and can last weeks, months, or, in a minority of cases, longer [1][2].

Typical symptoms include dizziness, electric-shock sensations (“brain zaps”), flu-like feelings, insomnia, anxiety, depressed mood, irritability, and, less commonly, movement problems or sensory disturbances [1][3]. These symptoms are generally unrelated to the original condition; their appearance after dose reduction or cessation is what distinguishes them as withdrawal phenomena rather than relapse.

How common and how severe?

Estimates vary. A 2019 systematic review found that about half of people who discontinue antidepressants experience withdrawal symptoms and roughly half of those rate them as severe [3]. A recent clinical review in Psychiatry at the Margins likewise notes that withdrawal “appears to be common, with a spectrum that ranges from mild and transient to severe and persistent” [1].

Time course and risk factors

Symptoms usually begin 24–72 hours after the last dose but can be delayed up to a week with longer-acting drugs such as fluoxetine [1][4]. Higher doses, longer duration of treatment, short half-life drugs (e.g., paroxetine, venlafaxine), and abrupt cessation all increase risk and severity [2][4].

Proposed mechanisms

Current hypotheses focus on receptor and transporter adaptations produced by prolonged serotonin or noradrenaline re-uptake blockade. When the drug is removed abruptly, these adaptations are suddenly unopposed, producing neurochemical instability that manifests as withdrawal symptoms [4]. The exact mechanisms remain under investigation.

Debates in terminology

Some clinicians prefer “discontinuation syndrome,” arguing it avoids the pejorative connotations of “withdrawal” and stresses that antidepressants are not classically addictive. Others argue that “withdrawal” is the more accurate pharmacological term and allows patients’ experiences to be taken seriously. As Psychiatric at the Margins points out, the dispute is “partly semantic and partly political,” but has real consequences for how rapidly drugs are stopped and how much support patients receive [1].

Managing withdrawal

Gradual tapering—sometimes over months—is the main strategy to reduce risk. The Psychiatry at the Margins article emphasizes hyperbolic tapering: progressively smaller dose reductions as one approaches zero, reflecting the non-linear relationship between dose and receptor occupancy [1]. Small compounding doses or liquid formulations can help achieve the necessary micro-reductions [2]. If severe symptoms emerge, guidelines recommend reinstating the previous tolerated dose and then tapering more slowly [4].

Public discourse and areas of disagreement

1. Prevalence and severity. Older guidelines suggested withdrawal is usually “mild and self-limiting.” More recent patient surveys, systematic reviews, and the 2019 Royal College of Psychiatrists statement acknowledge it can be severe and prolonged for some people [3].
2. Framing. Critics argue that minimising withdrawal risk contributed to long-term, sometimes indefinite prescribing. Proponents of a more cautious stance, including Awais Aftab in Psychiatry at the Margins, call for balanced messaging that neither exaggerates nor downplays risks [1].
3. Research gaps. There are few randomised tapering trials, and the field lacks consensus on optimal tapering schedules or biomarkers to predict risk.

Despite these debates, recent professional statements and patient-led advocacy have produced greater recognition that withdrawal is both real and, for a subset of patients, clinically significant.

Sources

1. Aftab, A. “When it comes to SSRIs, are our only options a lifetime of medication or recurrent illness?” Psychiatry at the Margins (2023). https://www.psychiatrymargins.com/p/when-it-comes-to-ssris-are-our-only
2. National Institute for Health and Care Excellence (NICE). “Depression in adults: treatment and management.” NG222 (2022). https://www.nice.org.uk
3. Davies, J. & Read, J. “A systematic review into the incidence, severity and duration of antidepressant withdrawal effects: Are guidelines evidence-based?” Addictive Behaviors (2019).
4. Fava, G.A. et al. “Withdrawal symptoms after selective serotonin reuptake inhibitor discontinuation: a systematic review.” Psychotherapy and Psychosomatics (2015).

Suggested Sources

https://www.psychiatrymargins.com/p/when-it-comes-to-ssris-are-our-only