Depression is a serious medical condition; it is more than just "the blues" or being "down." It is an illness with physiological underpinnings and can be alleviated with medications. Antidepressants are often prescribed for people who display signs of clinical depression. There are various kinds of antidepressants, and you might have to try more than one before finding one that brings relief.
MAOIs
Monoamine oxidase inhibitors (MAOIs) were developed in the 1950s and were the first kind of antidepressants, according to the Mayo Clinic. It is thought that these drugs work by stopping monoamine oxidase, an enzyme, from breaking down serotonin, dopamine and norepinephrine, the clinic reports. This helps keep the brain levels of these neuroransmitters high, thus elevating mood. Drugs in this class include phenelzine, tranylcypromine, and selegiline. Side effects of MAOIs include weakness, impaired sexual functioning, low blood pressure, lowered urine output, nausea, diarrhea, dry mouth and sleep disturbances, the Mayo Clinic reports.
MAOIs are not prescribed as often as other classes of antidepressants because there are several serious safety precautions that must be followed. These medications can interact with foods that are high in a chemical called tyramine, which can include cheeses, pickled foods, chocolate, alcohol, and some meats, and result in stroke, the Mayo Clinic reports.
SSRIs
Selective serotonin reuptake inhibitors (SSRIs) include the drugs fluoxetine, citalopram, paroxetine, sertraline, and escitalopram. Fluoxetine was the first SSRI, and was formulated in 1987, according to the Mayo Clinic. Although the precise mechanism is not known, it is thought that these drugs block serotonin from being reabsorbed by brain receptors, which leaves more serotonin in the brain to boost mood, according to the Mayo Clinic. Side effects of SSRIs commonly include dry mouth, sexual dysfunction, drowsiness and diarrhea, the Mayo Clinic reports.
SNRIs and NDRIs
Serotonin and norepinephrine uptake inhibitors (SNRIs) work like SSRIs, but on both serotonin and norepinephrine, instead of only serotonin. Both of these neurotransmitters help elevate mood, and so increased levels of these chemicals in the brain helps to boost mood and alleviate depression, according to the Mayo Clinic. The two drugs in this class are duloxetine and venlafaxine. The Mayo Clinic lists side effects that include constipation, sweating, dizziness, nausea, tremor, anxiety, headache and sexual dysfunction.
Norepinephrine and dopamine reuptake inhibitors (NDRIs) block the uptake of norepinephrine and dopamine in the brain, allowing larger amounts of these neurotransmitters to remain, boosting mood, the Mayo Clinic reports. Buproprion is an NDRI, which has side effects that can include a loss of appetite, weight loss, constipation, trouble sleeping and shakiness, according to the Mayo Clinic.
