Among the various treatments for depression is a class of drugs called antidepressants. Antidepressants are a number of classes of drugs that regulate chemicals in the brain which help to regulate moods and behaviours. First developed in the 1950s, they have since been improved on and are generally broken into several major classes, including selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), monoamine oxidase inhibitors (MAOIs), and antipsychotics.
Aside from depression, these medicines are also known to treat anxiety, obsessive-compulsive disorder, post-traumatic stress disorder, and eating disorders, among other mood and behaviour related disorders. Today it is estimated that about ten per cent of Americans are on some form of antidepressants.
Many antidepressants share similar side effects, however, every antidepressant should be considered individually in its side effects, and should be discussed with your doctor. It should be taken into account that all antidepressants are required to carry a black-box warning about the potential for suicidal thoughts and behaviours.
SSRIs
Serotonin is a neurotransmitter present in the brain. Neurotransmitters are chemicals that help send messages from the end of nerve fibres to other nerves, or to muscles or other structures.
Low serotonin levels have been associated with depression and anxiety, along with other mental disorders. As the name suggests, SSRIs prevent the “reuptake” of serotonin back into nerve endings, which in turn makes them more available in the brain. SSRIs are among the most common antidepressants, and you are probably already familiar with the most popular ones: Prozac, Zoloft, Paxil, and Celexa.
Side Effects of SSRIs
- Nausea
- Anxiety
- Diarrhea
- Headaches
- Dizziness
- Dry mouth
- Weight gain
- Loss of libido
- Thoughts of self-harm
- Flu-like symptoms
SNRIs
Serotonin and norepinephrine reuptake inhibitors work similarly to SSRIs. The added benefit of SNRIs is that along with serotonin, they also prevent the reuptake of norepinephrine, allowing for an abundance of this helpful neurotransmitter as well. They were introduced to the US market in the mid-90s as having a slightly added benefit to the then-popular SSRIs.
Side Effects of SNRIs
- Nausea
- Dry mouth
- Headache
- Sweating
- Dizziness
- Tiredness
- Constipation
- Insomnia
- Loss of libido
- Loss of appetite
SNRIs are also known to interact with certain drugs and particular diets, so be sure to speak to your doctor directly when considering an SNRI for your symptoms.
MAOIs
MAOIs were the first class of antidepressant developed in the early 1950s. Although they are occasionally still in use today, many have fallen out of favour due to concerns with various food and drug interactions.
MAOIs by inhibiting an enzyme called monoamine oxidase, which in turn elevates the levels of norepinephrine, serotonin, and dopamine. Monoamine oxidase breaks down these neurotransmitters, and when monoamine oxidase is inhibited, they are not broken down.
Side Effects of MAOIs
- Nausea
- Vomiting
- Weight gain
- Impotence
- Anxiety
- Suicidal thinking and behaviour in children and young adults
Because MAOIs interact with certain seizure medications, other antidepressants, as well as certain foods, it is not recommended to take MAOIs without first disclosing all of your present medications with your doctor. It is also important to speak to your doctor about strict dietary restrictions that could prevent elevated blood pressure and hypertensive episodes.
Antipsychotics
Certain antipsychotics, specifically Seroquel, Abilify, and Zyprexa, have been approved by the FDA as a secondary treatment for depression. Sometimes working best in combination with other antidepressant medication, these antipsychotics have been shown to have helpful additional effects in treating depressive episodes. The medications are only known to be helpful in combination with other antidepressants in sub-antipsychotic doses, meaning doses smaller than those used to treat various forms of psychosis.
Side Effects of Antipsychotics
- Drowsiness
- Dizziness
- Restlessness
- Weight gain
- Dry mouth
- Constipation
- Nausea
- Vomiting
Of course, there are also long term effects of antipsychotics like Seroquel that should be taken into consideration as well.
Discontinuation of Various Anti-Depressants
You should always consult a doctor if you wish to lower your dose or quit taking anti-depressants. As mentioned above, there can be serious side effects to quitting anti-depressants cold turkey without a doctor’s supervision. Talk to your doctor about any medication changes instead of taking the issue into your own hands and you can avoid some potentially fatal side effects.
Conclusion
Antidepressants can be helpful in remedying a number of mental disorders, however, they are serious medications which can have serious side-effects. Because of the potential side effects of each medication, you are on, it is important to be candid with your doctor when considering any new medication, especially antidepressants.
