Serotonin sends signals between nerve cells and narrows the blood vessels. The neurotransmitter regulates functions throughout the body, including the cardiovascular, immune, gastrointestinal and central nervous systems. Serotonin alters brain chemistry to adjust mood, sleep and sexual function. Medication can affect levels and actions of serotonin to treat certain mental and physical disorders.
Anxiety
Doctors have found that certain antidepressants work on serotonin to improve moods for people with anxiety disorders. Selective serotonin reuptake inhibitors, or SSRIs, block the absorption of serotonin by the brain. Absorption normally takes place after serotonin performs a function. By blocking the process, more serotonin becomes available for patients to relieve anxiety, according to the Anxiety Disorders Association of America. The serotonin-altering medications work effectively for generalized anxiety disorder, panic disorder, phobias and post-traumatic stress disorder. People with obsessive-compulsive disorder benefit when using higher doses of the medication. Other antidepressants called serotonin-norepinephrine reuptake inhibitors, known as SNRIs, increase levels of serotonin and norepinephrine, an adrenal hormone.
Depression
Antidepressants, of course, also benefit people with depression. Drugs involved with increasing serotonin levels help to improve moods and emotional responses in patients. SSRIs are the most popular types of antidepressants for depression, according to the National Institute of Mental Health. Drugs include sertraline, fluoxetine, citalopram, escitalopram and paroxetine. Doctors also prescribe SNRIs, such as duloxetine and venlafaxine. These drugs are also prescribed for anxiety disorders. SSRIs and SNRIs are among the newer class of drugs that have fewer side effects overall than older drugs. However, altering serotonin levels may affect sexual function and some patients report sexual side effects that include loss of interest or dysfunction from SSRIs and SNRIs. Doctors may add a second antidepressant, such as bupropion, which affects the neurotransmitter dopamine, involved with adrenaline, to ease sexual side effects.
Sleep Disorders
Low levels of serotonin may result in disturbed sleep patterns, according to CBC News. Serotonin levels, measured through blood tests, were found to be lower among 437 day workers when compared to 246 workers on rotating shifts by researchers at the University of Buenos Aires. The shift workers experienced a poor quality of sleep, sleeping one to four hours less than average, the researchers concluded. Poor sleep quality may affect work performance, risking accidents or injury. Medications that affect serotonin levels help to improve sleep for people with sleeping disorders. They can be especially helpful for patients with depression and disturbed sleep. Doctors may prescribe trazodone, which affects serotonin levels, for sleep disorders.
