Antidepressant
Overview
Antidepressants are a class of medications that are primarily used to treat depression. These drugs can also be used for other mental health conditions such as anxiety, OCD, PTSD, and certain chronic pain conditions. Antidepressants work by balancing chemicals in the brain called neurotransmitters, which affect mood and emotions.
History
The development of antidepressants began in the 1950s with the introduction of monoamine oxidase inhibitors (MAOIs) and tricyclic antidepressants (TCAs). In the late 1980s, selective serotonin reuptake inhibitors (SSRIs) were introduced, which have fewer side effects and are safer in overdose compared to their predecessors.
Types of Antidepressants
There are several types of antidepressants, each working in a slightly different way and having different side effects.
Selective Serotonin Reuptake Inhibitors (SSRIs)
SSRIs are the most prescribed type of antidepressants. They work by increasing levels of serotonin in the brain. Examples of SSRIs include fluoxetine, sertraline, and citalopram.
Serotonin and Norepinephrine Reuptake Inhibitors (SNRIs)
SNRIs are similar to SSRIs but also affect norepinephrine levels. Examples of SNRIs include venlafaxine and duloxetine.
Tricyclic Antidepressants (TCAs)
TCAs are older drugs that provide effective treatment but often have more side effects than newer drugs. Examples of TCAs include amitriptyline and nortriptyline.
Monoamine Oxidase Inhibitors (MAOIs)
MAOIs are older drugs that are most commonly used when other treatments are ineffective. They have more side effects than newer drugs and require a strict diet because of dangerous (or even deadly) interactions with certain foods.
Atypical Antidepressants
This group includes drugs that do not fit into the other categories. They have unique mechanisms of action and side effects. Examples include bupropion and mirtazapine.
Mechanism of Action
Antidepressants work by affecting the neurotransmitters in the brain. Neurotransmitters are chemical messengers that transmit signals between nerve cells in the brain. Most antidepressants work by increasing the availability of certain neurotransmitters or by changing the sensitivity of the receptors for these chemical messengers.
Side Effects
Like all medications, antidepressants can cause side effects. Not everyone experiences the same side effects, and some people may not experience any. Common side effects can include nausea, increased appetite and weight gain, loss of sexual desire and other sexual problems, fatigue and drowsiness, insomnia, dry mouth, blurred vision, and constipation.
Effectiveness and Risks
Antidepressants are effective in treating depression, but they come with risks. The benefits must be weighed against the potential risks, which can include worsening symptoms, suicidal thoughts, especially in children, teenagers, and young adults, serotonin syndrome, an uncommon but potentially serious condition that can occur if the levels of serotonin in the brain become too high, and discontinuation syndrome, a reaction that can occur when stopping or reducing the dosage of an antidepressant.