Prevention of discontinuation syndrome

• Prevention
  • Tapering after successful treatment
    • Recommendations on taper length vary
      • has been suggested that antidepressants administered for 8 weeks or more should, wherever possible, be reduced over a 4-week period
      • NICE suggest that
        • normally, gradually reduce the dose over 4 weeks (this is not necessary with fluoxetine). Reduce the dose over longer periods for drugs with a shorter half-life (for example, paroxetine and venlafaxine)
          
          
    • routine tapering is probably unnecessary when antidepressants have been prescribed for less than 4 weeks, as discontinuation symptoms are unlikely to occur with such a short duration of treatment (2)
    • an abruption of an antidepressant is justified if a patient has developed serious side effects believed to be due to the antidepressant, there is a medical emergency warranting stopping the antidepressant or the antidepressant has induced mania (2)
      
      
  • Tapering and antidepressant switching
    • data imply that if tapering SSRIs and venlafaxine is beneficial in reducing discontinuation symptoms, then it needs to continue for more than 14 days for most patients.
    • a start-taper switch refers to starting the new antidepressant and simultaneously gradually tapering the previous one
      • whether an abrupt switch or start-taper switch is chosen partly depends on the likelihood of discontinuation symptoms occurring, which in turn depends on the pharmacological similarity between the two antidepressants
    • using a washout period (no antidepressant prescribed)
      • is essential when switching to and from MAOIs because of the risk of drug interactions that can lead to serotonin syndrome
      • a washout should also be considered when switching from fluoxetine to a TCA, as the long-half life of fluoxetine, plus its ability to inhibit cytochrome P450 enzymes, could result in elevation of plasma TCA levels, leading to adverse effects (2)
        
        

Reference:

• Renoir T. Selective Serotonin Reuptake Inhibitor Antidepressant Treatment Discontinuation Syndrome: A Review of the Clinical Evidence and the Possible Mechanisms Involved. Front Pharmacol. 2013; 4: 45.
• Haddad PM, Anderson IM. Advances in Psychiatric Treatment 2007; 13: 447-457
• Haddad, PMThe SSRI discontinuation syndrome. Journal of Psychopharmacology 1998; 12: 305-313.
• Tint, A., Haddad, P. M, Anderson, I. M. The effect of rate of antidepressant tapering on the incidence of discontinuation symptoms: a randomised study. Journal of Psychopharmacology 2007
• NICE (October 2009). Depression