How do Antidepressants Work? | Are Antidepressants Effective? | What Happens During a Typical Treatment? | Are there Side Effects? | What Kinds of Antidepressants are there? | How Do I Take Antidepressants Safely?
If you have depression, you will know that it’s more serious than everyday sadness.
Feelings of hopelessness, emptiness, or even worthlessness may cloud your mood. The activities that once gave you joy leave you feeling hollow, and on your worst days, you are troubled by thoughts of death or ending your life. Unlike regular sadness, these feelings refuse to pass.
Depression is a serious mental health condition, but it can be treated.
Antidepressants are one possible treatment you could consider. These are tablets commonly used to target the symptoms of depression and can be helpful on your journey to recovery.
How do Antidepressants Work?
Scientists aren't exactly sure how antidepressants work, but they believe the medicine influences how the brain makes certain chemicals.
Your brain contains a network of neurons, string-like cells that deliver messages between the body and the brain. To do this, they create and send each other chemicals called neurotransmitters.
Some neurotransmitters, like serotonin, help send messages across the brain that balance your mood. In the brains of people with depression, there are problems with neurotransmitter activity, which can trigger unhealthy changes in their emotional state.
Antidepressants are thought to increase the amount of neurotransmitters in the brain. This in turn helps to bring your mood back into balance.
Are Antidepressants Effective?
The severity of your depression can impact how well antidepressants will work for you.
Depending on how many symptoms of depression you have, their intensity, and how far they stop you from finishing daily tasks, doctors will classify your depression as either mild, moderate, or severe.
Generally, the more serious your depression is, the more likely it is that the medication will work well. This means that they are effective for moderate to severe depression, but are less likely to work in milder cases.
If you do have mild depression, but other treatment options haven’t worked for you, then you and your doctor can discuss using antidepressants. If you don’t feel any improvements after a few months, your doctor may recommend alternative treatments.
Do Antidepressants Treat Root Causes?
While antidepressants treat the symptoms of depression, they don’t combat the root causes. It can help with, for example, low mood and sleep problems caused by depression, but it won’t fix the emotional or personal issues driving your condition.
As a result, it might be useful to combine antidepressants with talking therapy, which can help address your condition's deeper causes.
Can Antidepressants Stop Relapses?
Studies suggest that common antidepressants can reduce the risk of depression coming back (relapse), but they aren’t able to prevent this from happening completely.
To help prevent a relapse, some people with depression may take antidepressants for 1-2 years, sometimes even longer. People who take them for this length of time often have long-term (chronic) depression, have had many relapses in the past, or are keen to prevent future relapses.
What Happens During a Typical Treatment?
Your treatment plan will not look exactly the same as someone else's, but there are some common stages you can expect when you begin treatment with antidepressants.
Deciding on an Antidepressant
Every person’s brain and body are unique, so an antidepressant that works well for one person may not work for others.
To figure out which kind of antidepressant is most suitable for you, your doctor will guide you through questions like:
Which symptoms of depression bother you the most?
Do you take any other supplements or medicines?
Is there a history of depression in your family? Did any of your family members take antidepressants?
Do you have any other health conditions?
Are you pregnant, breastfeeding or planning for pregnancy?
As you go through your treatment, you may have to try a few different kinds before you find one that works best for you.
Starting your Treatment
Antidepressants are usually taken as tablets, and depending on how serious your depression is, you can take them 1-3 times a day. Your doctor will start you on a low dose so your body can adjust more easily to the medicine, then slowly increase your dose over time.
It can take up to four weeks for you to feel your symptoms improving. If you don’t observe any improvements after this time, your doctor might:
Change your dose, or the type of antidepressant you’re using.
Test your blood to see if enough of the medicine has entered your bloodstream.
Add another antidepressant to your treatment.
Prescribe other medicines to boost the effects of your antidepressant.
Double-check your diagnosis to see if it’s accurate, or if you have another condition.
Stop the treatment temporarily or permanently.
Recommend an alternative treatment, such as talking therapy.
Coming off Your Treatment
Treatment typically lasts 6-12 months. However, depending on the severity of your condition, you may need to take them for longer, sometimes over many years. Your doctor can advise you on what a suitable length of treatment is for you.
As you reach the end of your treatment, your doctor will begin to slowly drop your dose over 6-8 weeks.
You may experience some temporary side effects, such as sleep issues, restlessness and nausea. These side effects usually go away within 2-6 weeks, but if you find them too uncomfortable, your doctor can return to giving you your original dose, and then drop it in smaller amounts over time.
Changes in your dose must be gradual, as any sudden increases or decreases can cause withdrawal. Withdrawal happens when your body doesn’t have enough time to adjust to how much medicine you’re taking. It can cause symptoms like:
Chills
Nausea
Muscle aches
Dizziness
Anxiety
Irritability
Aggression
Sleep problems
Flu-like symptoms, such as headaches, achiness, sweating and fatigue
Tiredness
Feeling like an electric shock is firing through your head
These symptoms are usually mild and improve on their own, but can be severe and last for many months in some cases.
Are there Side Effects?
Not everyone will experience side effects with antidepressants, but if you do, be assured that they are a normal part of the treatment. It’s a sign that the medication is working and that your body is adjusting. They are usually mild and go away on their own after a few weeks.
Some common side effects brought about by antidepressants can include:
Nausea and vomiting
Diarrhea or constipation
Stomach aches and indigestion
Weight gain
Sexual problems, like problems getting an erection and lower sex drive.
Sleepiness and drowsiness
Dizziness
Headaches
During your first week of taking antidepressants or increasing your dose, you may feel more agitated and anxious, and your depression might feel slightly worse.
These side effects should improve within a few weeks, but if they persist, or become more intense, tell your doctor. They can help you manage these side effects, or may recommend changing your dose or the type of antidepressant you’re using.
If you notice any worrying changes, like unusual changes to your behaviour or mood, make sure to also tell your doctor as soon as possible.
Can Antidepressants Give me Diabetes?
Long-term use of SSRIs or TCAs may increase the risk of developing Type 2 Diabetes.
However, researchers are unsure if they cause diabetes directly. Antidepressants can cause weight gain, and this weight gain may be what actually makes you more vulnerable to diabetes.
If you have any worries about diabetes and antidepressants, your doctor will be available to guide you.
What if I Find the Side Effects too Uncomfortable?
If your have mild depression, you're struggling to tolerate side effects, and your antidepressant doesn’t bring much improvement, your doctor may recommend finding another treatment option.
However, if you experience uncomfortable side effects, but your depression is severe, it may be worth continuing the treatment. Side effects can be unpleasant, but this should be weighed up with the risks of leaving your depression untreated.
Your case will have its own unique needs, and your doctor can guide you towards making a well-informed decision.
What Kinds of Antidepressants are there?
Doctors use a variety of different antidepressants to treat depression. Each kind works slightly differently and has its own arsenal of possible side effects.
Selective Serotonin Reuptake Inhibitors (SSRIs)
SSRIs are the most commonly prescribed antidepressant as they cause fewer side effects than other types.
They stops nerve cells in the brain from reabsorbing serotonin, a neurotransmitter that controls mood and emotion. This means the brain stores or breaks down less serotonin, and more is left over to help balance your mood.
You should avoid taking SSRIs if you have:
Bipolar disorder, especially if you’re feeling extremely excitable (a manic phase).
SSRIs, however, can be helpful during depressive phases
A bleeding disorder
Type 1 or Type 2 Diabetes
Epilepsy. SSRIs can only be taken if the epilepsy is under control
Kidney disease
Serotonin-Norepinephrine Reuptake Inhibitors (SNRIs)
Like SSRIs, SNRIs target serotonin, but they also stop nerve cells from reabsorbing, storing and breaking down norepinephrine, a neurotransmitter that controls alertness, focus and attention.
If you begin taking SNRIs at higher doses, you may become vulnerable to high blood pressure. Because of this, it's not advisable to take SNRIs if you have a history of heart disease, or hypertension. This is a condition where your body cannot regulate high blood pressure.
Norepinephrine-Dopamine Reuptake Inhibitors (NDRIs)
It’s not exactly clear how NDRIs work, but experts believe it also impacts how the brain makes norepinephrine. It also targets dopamine, a hormone that actives motivation and pleasure.
Since dopamine and norepinephrine also control attention and focus, NDRIs can be useful for those who have ADHD as well as depression. NDRIs can also help those trying to quit smoking, as dopamine helps manage the brain's reward and addiction systems.
In a small number of people, taking NDRIs can lead to high blood pressure (hypertension), but in most cases, it has little effect on your heart's health.
NDRIs can also increase the risk of you having a seizure. You are especially vulnerable if you also have bulimia.
Monoamine Oxidase Inhibitors (MAOIs)
MAOIs are the oldest type of antidepressant. They combat depression by stopping the brain from breaking down serotonin, dopamine and norepinephrine.
Though highly effective, MAOIs can cause life-threatening cases of extremely high blood pressure, or 'hypertensive crisis'. Doctors therefore only prescribe them when other treatments haven't worked.
If your doctor prescribes you MAOIs, you'll have to follow a diet that avoids foods and drink containing a compound called tyramine. These include food and drink items like broad beans, raisings, yoghurt, cheese, soy sauce, malted beer, sherry and liquor.
You would also need to avoid taking sympathomimetic medications, often used to treat conditions like asthma, low blood pressure, cardiac arrest, premature labour and glaucoma.
Tricyclic Antidepressants (TCAs)
TCAs are usually not the first antidepressant that doctors will prescribe you, as their side effects can be more unpleasant. An overdose on TCAs can also be more dangerous when compared to overdoses on other antidepressant types.
If you have severe depression that has resisted other treatments, your doctor may make an exception.
There are some situations where TCAs are not suitable. This applies if you have:
Liver disease
A history of heart disease
Recently had a heart attack
An inherited blood disorder called porphyria
Bipolar disorder
Schizophrenia
Cancer on your adrenal glands which causes high blood pressure (Pheochromocytoma)
An enlarged prostate gland
Glaucoma
Epilepsy
How Do I Take Antidepressants Safely?
When you start taking antidepressants, there are steps you can follow to take them safely.
Make sure you follow your doctor’s instructions and to read the patient health leaflet which comes with the medicines.
Tell your doctor about every medicine, supplement, herb and over-the-counter medication you are using. These could interact with your antidepressant and make you feel ill.
Get all your medicines from the same pharmacy. Your pharmacist and doctor can see every medication you are getting and warn you beforehand if there are any risks when taking them with antidepressants.
Make sure you don’t stop taking your medication suddenly, even if you feel better. Doing this can cause withdrawal and could increase the risk of your depression returning.
Make sure you don’t miss a dose. In the long-term, this can reduce how well the treatment works and can also cause withdrawal.
Have regular appointments with your doctor to talk about side effects you’re experiencing and how well your symptoms are improving. They can then adjust your treatment if necessary.
Avoid alcohol and illegal drugs, as they can make the symptoms of your depression worse. If they interact with your antidepressants, you could also experience unpredictable side effects. If you do drink alcohol or take drugs, make sure you tell your doctor before you begin taking your medication.
Can you Take Antidepressants as a Child or Young Person?
If you’re under 18 and have moderate depression, your doctor may not recommend antidepressants to you as a first line of treatment. Some research shows that, in rare cases, antidepressants can increase the risk of self-harm and thoughts of suicide if you are in this age bracket.
However, if you have moderate to severe depression, and other treatments haven’t worked, your doctor may consider putting you on antidepressants despite the risk.
If your doctor gives you a prescription, they will put certain safety measures in place to protect you. These may include:
Advising you to attend talking therapy at the same time.
Bringing in a child and adolescent psychiatrist to monitor your treatment. This is a doctor who specialises in mental health conditions in children and young people.
If you are 25 or under and are taking antidepressants, consider telling a close friend or trusted relative about your treatment, and ask them to read the patient information leaflet which comes with your tablets. By doing so, they can monitor any worrying changes in your behaviour.
If you have thoughts of harming or killing yourself, talk to your doctor about what you’re experiencing, or go straight to an Accident and Emergency department for help.
Can you Take Antidepressants as an Elderly Person?
Antidepressants come with certain risks if you are an elderly person. You may still be able to take them, but it's worth considering the following:
Elderly people may have multiple health issues they are being treated for, so they may be taking a few kinds of medication at once. This makes it more likely that a medicine will interact with the antidepressant and cause unwanted side effects.
You may be more sensitive to side effects. To make these less intense, your doctor may start you off on an antidepressant with fewer side effects, like an SSRI or SNRI, and give you the lowest possible dose that is still effective.
Hyponatremia
Antidepressants, especially SSRIs, can cause Hyponatremia in the elderly. This is a condition where the salt levels in your body drop dramatically, causing fluid to clog up your cells.
Mild Hyponatremia can trigger depression-like symptoms, and can bring about side effects that you usually get when taking antidepressants (nausea, headache, muscle pain, confusion, lack of appetite).
If your condition is severe, you may feel tired and restless, disoriented, agitated, and may experience seizures or psychosis. In the most severe cases, Hyponatraemia can make you stop breathing or cause a coma.
If you suspect you have Hyponatremia, call your doctor so they can manage your condition. If you think you have a severe case, call your emergency service and ask for an ambulance immediately.
Can you Take Antidepressants if You're Pregnant?
If you're pregnant, antidepressants may cause complications for you and your baby, so your doctor may advise against using them.
On the other hand, having depression while pregnant can negatively impact the well-being of you and your baby. Depression and anxiety can also become more intense during pregnancy and after birth. If this applies to you, you may want to treat your depression more urgently.
Talking to your doctor can help you weigh up the risks and benefits of taking antidepressants while pregnant. With their help, you can find the safest treatment plan for you and your baby.
Can you Take Antidepressants if You're Breastfeeding?
It’s possible to take some kinds of antidepressants if you’re breastfeeding, but your doctor must assess your baby’s health first. If your baby is healthy, your doctor may be able to prescribe them.
Can you Overdose on Antidepressants?
Antidepressants are safe to use, but it is possible to consume too much in one go. Taking an amount of antidepressant over the recommended amount can be poisonous, a situation healthcare professionals call an ‘overdose’.
If you suspect that you or someone you know has overdosed on antidepressants, it’s essential to get an assessment form a healthcare professional immediately.
The symptoms of an overdose can vary from person to person, but you should call an emergency service if you experience:
Heart rhythm issues
Low blood pressure
Drowsiness
A coma
Blurry Vision
Tight muscles
Confusion
Seizures
Depressed breathing
Muscle twitching
A fever
Serotonin Syndrome
Taking too much MAOI, SSRI or SNRI can lead to dangerously high levels of serotonin in your body, a condition called serotonin syndrome.
The symptoms can be so mild that you don’t feel them. Nevertheless, you still need urgent medical assistance and may need to be hospitalised.
If left untreated, serotonin syndrome can escalate into muscle breakdown and dangerously high body temperature.
Serotonin syndrome can cause other problems, which include:
Muscle spasms in body parts from the hips down (clonus)
Hyperactive muscle reflexes (Hyperreflexia)
Tremors
Sweating
Dilated pupils
Rapid pulse and breathing
Agitation
Confusion
Delirium
Are there other Options?
If antidepressants haven’t worked for you, or you want to explore different treatments, there are other options available.
Cognitive Behavioural Therapy (CBT): A talking therapy which helps you challenge negative thought patterns that could be fuelling your depression. Experts suggest that combining CBT with antidepressants is very effective for people with moderate to severe depression, but CBT can be taken on its own too.
Interpersonal Therapy (IPT): This talking therapy guides you through how relationships with other people in your life could be impacting your condition. You may discuss problems like communication difficulties, isolation, coping with grief, and so on.
Counselling: Unlike CBT or IPT, counselling is best suited for generally healthy people who need guidance on a specific, short term issue, such as anger, grief, relationships, redundancy or infertility.
Support Groups: Talking regularly with other people dealing with depression can act as an encouraging support network. Having a safe space to express your feelings and being understood can help you cope with your condition.
Exercise: Research shows that exercising regularly can treat mild depression more effectively than antidepressants. It boosts serotonin and dopamine levels in the brain and can improve self-esteem.
Lithium Tablets: Your doctor may prescribe you Lithium if you’ve tried antidepressants without success. If you take Lithium, you need to take a blood test every few months, as high levels of lithium in the blood can be toxic. A certain level of salt can also make Lithium toxic, so you'll need to follow a low salt diet.
Electric Shock Treatment: An electric current is sent into your brain while you’re under anaesthetic. It can be very effective if you have severe depression and other treatments haven’t worked. However, after several months of treatment, the benefits usually taper off. You may also experience some short-term side effects including headaches, memory problems, muscle aches and nausea.
A Quick Review
Depression can make getting through your day feel like an impossible task, but treatments like antidepressants are available to help you.
By increasing the level of neurotransmitters in the brain, antidepressants can help stabilise your mood and combat the symptoms of depression. You could also combine antidepressants with other treatments, like talking therapies and other medications, to adjust your treatment plan to your needs.
Antidepressants can come with side effects, and you may need to try a few different kinds until you find one that works well for you.
Depending on your age, other medical conditions you may have, and whether you’re pregnant, there are other possible risks with taking antidepressants you should consider.
A healthcare professional can guide you through your options, monitor changes to your treatment, and discuss any worries you might have.
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Featured photo
https://www.vecteezy.com/free-photos/sadness Stock photos by Vecteezy
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