Serotonin Discontinuation Syndrome: Information for Primary Care
- Dave is a 25-yo male who presents on a Monday to the walk-in with a severe migraine.
- Symptoms of general malaise, flu-like symptoms and “electric shock” sensations.
- Medications: Has been taking Venlafaxine XR 300 mg daily for months for anxiety
- Unfortunately, he has not taken any since Friday because 1) he ran out of medications on Friday, and 2) went camping over the weekend…
Constellation of symptoms (such general malaise, flu-like symptoms, sensory disturbances) which can occur after a serotonin antidepressant is abruptly stopped.
- Onset usually within days of abrupt discontinuation of an SSRI, or SNRI, or missing a dose or various doses (such as “drug holidays”), or even reducing a dosage
- Symptom severity usually mild and self-limiting (usually 7-14 days) but may be distressing
- Symptoms resolve when the serotonin medication is (re)started
- Flu-like (eg. fatigue, lethargy, myalgia)
- Disequilibrium (eg. dizzy, vertigo, ataxia)
- GI (nausea, vomiting)
- Sensory disturbance (eg. paresthesia, sensations of electric shock)
- Sleep disturbance (eg. insomnia, vivid dreams)
- Anxiety, agitation, crying spells, irritability
- F)lu-like symptoms -- fatigue, lethargy, general malaise, muscle aches/headaches, diarrhea
- I)mbalance: Gait instability, dizziness/lightheadedness, vertigo
- S)ensory disturbances: Paresthesia, “Electric shock” sensations, visual disturbance
- H)yperarousal: Anxiety, agitation
- G)astro-intestinal – nausea, vomiting
- R)eally bad dizziness – dizziness, ataxia
- I)nsomnia – insomnia, vivid dreams
- E)lectric shock – shocks, paresthesias
- F)lu-like symptoms – fever, chills, fatigue, myalgia
- Although usually mild and not dangerous, symptoms can still be distressing for patients
- Symptoms may discourage patients from using medications in the future, out of concerns such as becoming ‘addicted’ or ‘dependent’ on medication
- Occurs in 20% of patients after abrupt discontinuation of antidepressants taken for at least 6-8 weeks (Warner, 2006).
- Occurs rarely if patients have had antidepressants for less than 6-8 weeks.
Factors which increase risk are:
- Short half-life SSRIs such as paroxetine, fluvoxamine, sertraline, or SNRIs such as venlafaxine
- Longer duration of treatment, such as at least 6-8 weeks
Symptoms of SSRI discontinuation can be seen in other conditions as well:
- SSRI discontinuation: Onset of symptoms usually within few days (e.g. 1-3 days) within stopping a medication.
- Bipolar manic episodes: Onset of irritability, insomnia, increased mood / agitation or self-esteem
- Relapse of depression: Usually occurs after 2-3 weeks
- Medication side effects: In situations where a patient is being switched from an older medication (such as SSRI) to a newer medication without the same serotonin activity, the onset of symptoms may appear to be side effects of a new medication, when in actuality, it is serotonin discontinuation syndrome
- Minimize use of SSRIs: Start with non-medication strategies prior to considering SSRIs for conditions such as depression and anxiety.
If SSRI is used:
- Use longer half-life SSRI, e.g. fluoxetine
- Avoid using medications with short half-life, e.g. paroxetine (Paroxetine) (SSRI), or venlafaxine (Effexor) (SNRI).
- Taper dose slowly, e.g. reducing dosages by 25% over 1-2 weeks). For patients who are sensitive to dose reductions, contact a pharmacy that can provide a special compounded prescription to make it easier to slowly reduce a medication.
- Educate patients about not stopping their SSRI suddenly, without the support of their physician.
- Reassure patients that even if they develop SSRIs, the symptoms are distressing, they are time limited.
- Increase SSRI dose if acute symptoms appear during tapering.
- If there are severe symptoms that persist, then consider switching to an SSRI with a long half-life, such as fluoxetine (Prozac).
- Dave is a 25-yo male who presents on a Monday to the walk-in with symptoms of serotonin discontinuation syndrome.
- He is given a prescription so that he can restart his Venlafaxine XR, and told to return if symptoms do not improve.
- He has rapid improvement of his symptoms and vows never to stop his medications without checking with his physician.
- Canadian Adverse Drug Reaction Newsletter, Vol 8(4), Oct 1998, www.hc-sc.gc.ca/hpb-dgps/therapeut
- Warner C et al: Antidepressant Discontinuation Syndrome, Am Fam Physician 2006 Aug 1; 74(3): 449-456.
If you are switching medications, or wanting to stop a medication, consider this resource
Date of Last Revision: Jan 21, 2018