Zosert tablets contain Sertraline 50 mg which is used in the treatment of depression, anxiety disorder, phobia, post traumatic stress disorder and obsessive-compulsive disorder. Zosert 50 mg Tablet is a selective serotonin reuptake inhibitor (SSRI) antidepressant. It works by increasing the levels of serotonin, a chemical messenger in the brain. This improves mood and physical symptoms in depression and relieves symptoms of panic and obsessive disorders. It is a controlled drug in Kenya and a valid prescription from a registered doctor is required to obtain the prescribed doses.