Mind Help


Antidepressants are a type of medication which is used to relieve the symptoms of depression. They are also used to treat other conditions like anxiety disorder, social anxiety disorder, post traumatic stress disorder and other types of mental health disorders.

Antidepressants – An Overview

Antidepressants belong to a class of drugs which are used to reduce or relieve symptoms of mental health conditions in individuals. Although they are primarily used for depression and depressive disorders in people, they can also be effective in easing symptoms of other psychiatric disorders. Mental health disorders affect the functioning and chemistry of your brain, which affects the way we feel. Antidepressants work by correcting the imbalances of chemicals in our neurotransmitters which are responsible for alterations in our mood and behavior. They were first introduced for use to the general public in 1950.

A study 1 defines antidepressants as a “key part in treating depression” which helps to “relieve symptoms and prevent depression from coming back.” Antidepressants are also approved 2 by the U.S. Food and Drug Administration (FDA) in treating other medical disorders like “obsessive-compulsive disorder, social phobia, panic disorder, generalized anxiety disorder (GAD), and post-traumatic stress disorder (PTSD).” However it might be noted here that antidepressants are by no means a cure for depression and are also not a long term solution. Depression is caused by a combination of psychological, biological and even social factors like relationships, lifestyle and coping skills which medications cannot address.

How Do Antidepressants Work

How Do Antidepressants Work

“Most currently available antidepressants target monoamine neurotransmitter function,” explains a 2017 study 3 . Our brain contains three primary molecules, or monoamines as they are chemically called. These molecules are responsible for our mood regulation. Their main function is to work as neurotransmitters where they are responsible for transmitting nerve signals from one receptor in our brain to the other. Although there is not much research carried out on the mechanism of action of antidepressants, they are believed to work by influencing these neurotransmitters, which in turn affects our mood. These three neurotransmitters in our brain are:

1. Serotonin

This neurotransmitter 4 is responsible for regulating our overall mood, sleep, memory, appetite, sexual desires and even our social behavior. It helps to stabilize our mood and helps us maintain a general feeling of well being.

2. Dopamine

This neurotransmitter’s role is to affect our decision making capabilities, our motivation, symptoms and signals of rewards and pleasure and our arousal. It is also known as the feel good chemical 5 as it is linked to how happy we feel overall. It can also affect our memory, focus and movement.

3. Norepinephrine

This chemical 6 is linked to our overall alertness and arousal. It is responsible for our reaction time and also our ability to focus and concentrate. Too much secretion of it can make us feel anxious or restless, which is marked by an increase in our heart beat and our blood pressure.

When people suffer from depression, the concentration of these chemicals in their brain gets low. Antidepressants are known to work by increasing the availability of these neurotransmitters in different ways. There are 5 different classes of antidepressants which work in their own ways, as stated by a 2021 study 2 . They all work by targeting the neurotransmitters in our synapse which modulates our overall mood and behaviour.

Types Of Antidepressants

Types Of Antidepressants

Antidepressants are classified according to their mechanism of action. There are 5 classes of them and each of them works in a slightly different way than the other.

1. SSRIs (Selective Serotonin Reuptake Inhibitors)

Reuptake inhibitors primarily work by preventing our neurotransmitters from getting reabsorbed by the body. They work collectively to ensure that all the neurotransmitters secreted by our brain are active and available to use in our brain itself. Selective Serotonin Reuptake Inhibitors 7 work by preventing the reabsorption of serotonin in our body. They are useful for treating depression, ADHD (attention deficit hyperactivity disorder), OCD (obsessive compulsive disorder), eating disorders and even premature ejaculation.They tend to have lesser side effects than other types of antidepressants. However, they can cause insomnia, tremors and sexual dysfunction in some people. Some examples of SSRIs are Citalopram, Fluvoxamine, Paroxetine, Sertraline, Fluoxetine among others.

Read More About Eating Disorders Here

2. SNRIs (Serotonin and Norepinephrine Reuptake Inhibitor)

SNRIs work in a manner similar to that of SSRIs. However, SNRIs 8 help to inhibit or prevent the reabsorption of both serotonin and norepinephrine by the body. They are a relatively new class of antidepressants and help to increase levels of both these chemicals in our brain. Research has shown that increasing our norepinephrine levels in our body along with levels of serotonin have been useful in people who have psychomotor retardation, which slows down our body movement and makes our thoughts fuzzy. SNRIs have been shown to be particularly useful in treating chronic pain along with generalized anxiety disorder, social anxiety disorder, post-traumatic stress disorder along nerve pain. Some common side effects of SNRIs are fatigue, drowsiness, constipation, and nausea.

Read More About Generalized Anxiety Disorder Here

3. Tricyclic Antidepressants

Tricyclic antidepressants are named so as they have three rings in their atomic structure. They were one of the first antidepressants to be used and till today they are considered as effective 9 in dealing with depression and other mental health conditions. These drugs work by allowing more of your norepinephrine and serotonin to be released into your brain. Thus, they have an elevated effect on your mood. These drugs are generally prescribed to those individuals who do not respond well to other types of treatments. They are generally used for people suffering from migraine and chronic pain. This antidepressant affects our motor movement and may interfere with our digestion. It also sometimes blocks a naturally occurring chemical in our body called histamine 10 . This can lead to dry mouth, blurred vision, glaucoma and even constipation.

Read More About Chronic Pain Here

4. Monoamine oxidase inhibitors (MAOI)

This drug primarily works by inhibiting the action of a brain enzyme called monoamine oxidase. Monoamine oxidase breaks down the neurotransmitters like serotonin in our brain. When MAOIs 11 inhibit the action of this enzyme, more serotonin gets available for use in our brain. This leads to stabilization of mood in people and decreased levels of anxiety. MAOIs are used in cases where SSRIs do not work. They affect other medications and food items and thus can produce unwanted side effects. Some of the commonly reported side effects of MAOIs are blurred vision, edema, weight loss or gain, seizures, anxiety, insomnia, drowsiness among others.

Read More About Insomnia Here

5. Noradrenaline and specific serotonergic antidepressants (NASSA)

This class of drugs work by increasing amounts of serotonin and noradrenaline in our synaptic cleft, which is the space between our neurons at our nerve synapses where neurotransmitters send and receive messages. It also helps to block some serotonin receptors in our brain and thus, makes available more serotonin for our brain to use. Some of the side effects of NASSAs 12 are dizziness, drowsiness, dry mouth, constipation and weight gain.

Treatment With Antidepressants

Most antidepressants come in tablet form. A doctor usually prescribes the lowest possible for an individual to start with. This helps to ease some of the side effects of these drugs. The aim of most doctors is to relieve any symptoms in individuals and make their depression or mental health condition go away. Within seven days, most people start to feel 13 the effect of antidepressants. Most often, they need to be taken for several weeks or months without missing a single dose. If more than a month passes without one having felt any effects on their mood and their current conditions, it is recommended to talk to their physician about it.

The recommended duration of treatment is around four to nine months. Sometimes the individual might need a continuation therapy in order to prevent their depression from coming back. Individuals in some rare cases have been known to continue taking prescribed antidepressants for many years. It is important for the patient to have regular appointments with their doctor when they are ongoing their treatment. This way the physician will get to know about the effectiveness of the drugs and whether the symptoms are gradually decreasing with time. The doctor can also readjust the dosage or ask the patient to switch to a different drug if deemed necessary.

The dosage of the drugs are gradually reduced when one nears the end of his/her treatment. A person in this stage may experience insomnia, restlessness and nausea when coming off antidepressants. Although antidepressants do not cause any physical dependence or addiction, coming off them can be hard for some individuals and they might need post therapy counselling in such scenarios.

Side Effects And Risk Factors

Side Effects And Risk Factors

Most of the antidepressants today are considered generally safe. However, people react differently to different medications. Thus, the Food and Drug Administration has made it mandatory for all antidepressant drugs to come with a black box warning 14 , which is the strictest of all warnings for prescription drugs. Some of the general side effects 15 of antidepressants are”

  • Feelings of agitation
  • Indigestion and stomach pain
  • Constipation and Diarrhoea
  • Dizziness
  • Loss of appetite
  • Insomnia
  • Low sex drive
  • Erectile dysfunction in men
  • Blurring of vision and cottonmouth
  • Urinary problems
  • Excessive sweating
  • Tachycardia
  • Weight loss or gain

Apart from these, some other serious adverse effects of these medications may include:

1. Serotonin syndrome

According to research 16 , “Serotonin syndrome is a potentially life-threatening condition precipitated by the use of serotonergic drugs.” This occurs when individuals have high levels of serotonin in their brain. It can be caused due to an overdose of certain antidepressants like SSRIs and SNRIs. Some common side effects of serotonin syndrome are:

  • Diarrhoea
  • Sweating
  • Shivering
  • Agitation
  • Confusion
  • Muscles twitching

Individuals in severe cases can experience seizures, irregular heartbeats and even get unconscious.

2. Hyponatremia

“Hyponatremia is a common electrolyte abnormality caused by an excess of total body water when compared to total body sodium content,” explains researchers 17 .This symptom is common in elderly people who take antidepressants. This is especially caused by the actions of SSRIs, where there is a drastic decrease in the levels of sodium in our body. This can cause fluid to build up inside our cells, which can be life threatening in some situations. Side effects of hyponatremia are:

  • Headache
  • Feeling sick
  • Muscle pain
  • Confusion
  • Reduced appetite
  • Feeling exhausted
  • Seizures
  • Disorientation

In severe cases, individuals may be unable to breathe and may fall into a coma.

3. Suicidal thoughts

Suicide risk 18 is common in people using antidepressants, especially younger individuals. The age group for this risk is usually under twenty five years. This is because these drugs interact with the way natural chemicals in our body get secreted. “Some evidence suggests that Selective Serotonin Reuptake Inhibitors (SSRIs) may cause worsening of suicidal ideas in vulnerable patients,” explains a 2012 study 19 . Feelings of unusual thought and self harm implications arise within the first few weeks of starting antidepressants in young people.

Guidelines On Taking Antidepressants

People should be made aware of the type of drugs they are taking and the health implications it carries. Doctors should endeavor to make people aware about the safe usage of such drugs to avoid any unwanted side effects.

1. Follow instruction properly

When you are taking medications for depression and other mental disorders, it is advised to follow your doctor’s prescription 20 word by word. Never skip a dosage or take more than the prescribed quantity. Also, stop taking your medications only when your doctor advises you to do so.

2. Be aware of possible drug interactions

Sometimes, certain drugs can react with food 21 items or other medications or supplements you might be taking. Alcohol can interfere with the way these drugs work and make them less effective. Also some drugs like SNRIs and SSRIs can interact with certain painkillers, blood thinners and antihistamines, which are commonly found in over-the-counter medicines for allergies, common cold and sleeping aids. The reaction can be severe in some cases. Hence, it is advisable to let your doctor know of any other medication or food supplement you are taking.

3. Monitor your side effects closely

You should be keeping track of your physical and emotional changes in your body that you experience. You should always inform your physician about your side effects and contact them immediately if you find your symptoms deteriorating.

4. Engage in a holistic wellness regimen

If you continue to abuse drugs 22 , substances, drink or smoke, you may not fare well in your treatment. If you are addicted to substances 23 , you can always talk to a therapist about coming off it. You should endeavour to eat a healthy diet each day and also get plenty of sleep. Exercise can work wonders to uplift your mood and alleviate some of the side effects of these drugs.

5. Seek help

Although antidepressants are not addictive, many people experience withdrawal symptoms, once their treatment gets over. To avoid this, you can seek counselling or psychotherapy in order to help you cope in this period. Psychotherapy can also be beneficial in preventing your mental health conditions from coming back.


Antidepressants can go a long way in helping people with depression and other related health conditions. However, they should be used with precaution and never without a doctor’s prescription. Little is known about their side effects till now and it is best treated as a category of drugs which can be severely harmful to people.

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