New aspects in the treatment of depression

Because of the limitations in efficacy and safety of the older tricyclic antidepressants (TCA) and monoamine oxidase inhibitors (MAOI) a number of new approaches have been made in recent years to the treatment of depression to obtain more effective, more rapidly acting, better tolerated and safer drugs. One tactic has been to develop compounds with greater neuropharmacological selectivity in inhibiting the neuronal reuptake of 5-HT. Most of these are as effective as TCA but with fewer side-effects and greater safety. Another development has been 'reversible' MAOI which reduce the risk of interaction with tyramine-containing foods. For resistant depression the addition of lithium (and/or tryptophan) may be effective, possibly through promoting 5-HT neurotransmission. Continuous treatment with a selective 5-HT reuptake inhibitor can reduce the relapse rate in patients with recurrent depression. Unfortunately, these new approaches, despite their advantages in terms of side-effects and safety, have thus far not proved to be more effective or faster acting than the standard TCA. That remains a challenge for the future.