Selective serotonin reuptake inhibitors (SSRIs) are well known for their use in treating numerous central nervous system disorders, including depression and panic disorder. SSRIs are believed to increase the extracellular level of neurotransmitter serotonin by inhibiting its reuptake into the presynaptic cell, thereby increasing the level of serotonin in the synaptic cleft (the space between two communicating neurons). This serotonin is then available to bind to the postsynaptic receptor, providing antidepressant properties.

Psychiatrists and primary care physicians prescribing SSRIs generally regard them as effective, well-tolerated and easily administered treatments. However, they are associated with a number of undesirable features -- the list of side effects is extensive, and includes apathy, nausea, dizziness, weight loss/gain, mania and psychotic disorders, and suicidal thoughts, among many others.

SSRIs have been on the receiving end of much criticism over the last several years, with opponents asserting that the treatment is ineffective and highlighting its suspected link to suicide in adolescents taking SSRI-based medications. Because depression and other central nervous system disorders are often diagnosed without performing any physical examinations, critics question the validity of claims that SSRIs function by correcting chemical imbalances. If the patients’ neurotransmitter levels are not constantly monitored, how can the treatment’s physical activity be evaluated? Without measuring the pre- and post-treatment neurotransmitter levels, physicians can’t be sure that they haven’t overcorrected any chemical imbalances, and this may lead to further psychological issues.

Other opponents suggest that SSRIs’ effectiveness may be grossly exaggerated. According to a study in The New England Journal of Medicine, while 94 percent of studies published in various medical and psychiatric journals touted positive outcomes of SSRI treatment in patients with depression, when published and unpublished studies were included for analysis, only 51 percent reported positive outcomes. The study could not conclude whether this pointed to a purposeful skewing or merely a lack of submissions from unsuccessful studies, but was adamant that these results improperly convey SSRI treatments’ effectiveness to the public.

It is clear, therefore, that an equally efficacious but less adversely effective SSRI is needed.

Scientists at Neurosearch in Denmark believe they have done just that. Their patent claims a pharmaceutical composition comprising a therapeutically effective amount of a compound that optimizes the ratio of serotonin reuptake to non-adrenaline and dopamine reuptake activity. The compound is designed for treatment, prevention or alleviation of a disease or disorder that is responsive to inhibition of monoamine neurotransmitter reuptake in the central nervous system, such as depression or anxiety.