New Classification of Selective Serotonin Reuptake Inhibitor Withdrawal.

inal symptoms at the same intensity as before treatment, entailing a return of the same episode and a new episode of illness, respectively [6, 9] . When treatment with a CNS drug is discontinued, patients can experience classic new withdrawal symptoms, rebound and/or persistent postwithdrawal disorders, or relapse/recurrence of the original illness [6, 9, 14] . New and rebound symptoms can occur for up to 6 weeks after drug withdrawal, depending on the drug elimination half-life [2, 3] , while persistent postwithdrawal or tardive disorders associated with longlasting receptor changes may persist for more than 6 weeks after drug discontinuation. Initial withdrawal symptoms from CNS drugs have been reported to be more frequent and severe when high-potency drugs and drugs with a short elimination half-life have been used [9, 10] . CNS drugs with a shorter elimination half-life and rapid onset of action also carry a higher risk of dependency and high-dose use [9, 10] . Withdrawal symptoms can be relatively short-lasting, lasting for a few hours to a few weeks with complete recovery, while others may persist and last for several months [1, 15, 16] . Fava et al. [1] have proposed using the terminology ‘withdrawal syndrome’ to replace the term ‘discontinuation syndrome’, which has been most often used to describe SSRI withdrawal. They have recommended the Selective serotonin reuptake inhibitors (SSRIs) are widely used in clinical practice, and have advanced the treatment of depression and other mental disorders. However, more studies are needed on the effects of decreasing and discontinuing these medications after their long-term use [1] . Withdrawal symptoms may occur with all SSRIs and serotonin-noradrenaline reuptake inhibitors (SNRIs) [1] , similarly to other CNS drugs, including benzodiazepines [2–4] and antipsychotics [5, 6] . Withdrawal from SSRIs and other CNS drugs produces psychiatric symptoms that can be confounded with true relapse or recurrence of the original illness [1, 2, 7] . When discontinuing or decreasing SSRIs, withdrawal symptoms must be identified to avoid prolonging treatment or giving unnecessarily high doses [6, 8] . Different types of syndromes have been described with the withdrawal from SSRIs and other CNS drug classes, including benzodiazepines, antipsychotics, antidepressants, opiates, barbiturates, and alcohol: (1) new withdrawal symptoms (classic withdrawal symptoms from CNS drugs) [1, 4–6, 9–12] , (2) rebound [2, 6, 9, 13–16] , and (3) persistent postwithdrawal disorders [7, 17, 18] ( table 1 ). These types of withdrawal need to be differentiated from relapse and recurrence of the original illness. Relapse and recurrence are the gradual return of the origReceived: October 12, 2014 Accepted after revision: January 6, 2015 Published online: February 21, 2015