SELECTIVE SEROTONIN REUPTAKE INHIBITORS IN THE TREATMENT OF AFFECTIVE-DISORDERS - III - TOLERABILITY, SAFETY AND PHARMACOECONOMICS

The clinical use of tricyclic antidepressants (TCAs) is often complica ted by toxicity and safety problems due to their effects on multiple m echanisms of action, many of which are unnecessary for therapeutic eff ect. The development of the selective serotonin reuptake inhibitors (S SRIs), with their selective mode of action, has resulted in a class of antidepressant drugs possessing an improved side-effect profile, whil e retaining good clinical efficacy. Their introduction into clinical p ractice has led to enhanced patient compliance with antidepressant the rapy and the ability to maintain treatment over longer periods of time at an adequate therapeutic dose, Although, as a result of their selec tive action, side-effects associated with SSRI therapy are minimised, distinct variations between individual SSRIs in terms of their tolerab ility profiles have been observed. The wealth of clinical data now ava ilable has revealed differences in their potential to cause psychiatri c and neurological side-effects, dermatological reactions, anticholine rgic side-effects, changes in body weight, sexual dysfunction, cogniti ve impairment, discontinuation reactions and drug-drug interactions. P atients who suffer from concomitant depression and physical illness ma y experience different tolerability profiles, in addition to the great er likelihood that they will be receiving concomitant medications with the potential for pharmacokinetic drug-drug interactions with coadmin istered SSRI therapy. In addition, the safety margin of SSRIs in overd ose may vary within the group. Knowledge of the differences that exist among the SSRIs in respect of tolerability and safety will aid physic ians in the selection of the most beneficial treatment strategy for th eir patients. A successful clinical outcome leads to a reduced economi c burden for the patient, their family and the healthcare services. Th us, pharmacoeconomic considerations are also important in choosing ant idepressant therapy. The SSRIs, despite relatively higher prescription costs, have been demonstrated to be a more cost-effective option than the TCAs. Furthermore, there is evidence that the emerging clinical d ifferences between SSRIs may translate into significantly different ec onomic outcomes within the group.