Antidepressants are drugs which are used to treat clinical depression, although many of them are approved for use in other conditions as well. There are five main types:
- Tricyclic Antidepressants (TCAs)
- Selective Serotonin Re-uptake Inhibitors (SSRIs)
- Noradenaline Re-uptake Inhibitors (NRIs)
- Multiple Re-uptake Inhibitors
- Monoamine Oxidase Inhibitors (MAOIs)
2. How We Think They Work
It's not known for certain how antidepressants work, but most of them are thought to work by inhibiting the reabsorption of certain chemicals in the brain. For those of you who know nothing about the brain, let me run you through a couple of basics. The brain is made up of about 10 billion brain cells, or 'neurons'. Each one connects to about 10,000 others, but they don't actually touch one another. They are separated by small gaps called synapses. This is my fantastic diagram of two brain cells:
Brain cells communicate with each other by releasing chemicals called neurotransmitters, which other brain cells respond to. These chemicals are then either broken down or re-absorbed, because otherwise your neurons would be soaking in chemicals all the time, and they wouldn't be able to respond to other neurons any more. The most common antidepressants slow down the reabsorption of certain neurotransmitters, so that your neurons get longer to respond to them. That is why they are called 're-uptake inhibitors'. The three main neurotransmitters involved in depression are thought to be serotonin, noradrenaline and dopamine. SSRI's work on serotonin, NRI's work on noradrenaline, Multiple Reuptake Inhibitors work on two or more of the three and Tricyclics work on all three.
MAOI's work a bit differently; they slow down a chemical called Monoamine Oxidase, which breaks down neurotransmitters. The effect, however, is the same. Your brain cells get to soak in the right chemicals for longer.
3. Not Everyone Needs Medication
Antidepressants should not be used for treating mild depression for two reasons:
- Recent research shows that if you're not severely depressed, antidepressants don't work any better than placebos.
- While the placebo effect can be useful, antidepressants have risks and side-effects, so for those with mild to moderate depression, the risks basically outweigh any potential benefits.
Severe depression is different. If you're so depressed that you spend hours lying in bed trying to get up the strength to get up and make a cup of tea, it's pretty pointless for somebody to tell you that you need to get some exercise. That's the kind of depression where you need medication straight away.
4. They Don't Work Straight Away
Some people respond almost immediately to antidepressants, but others may not notice any difference for up to a month after they start taking, or six weeks for fluoxetine (Prozac). If there's still no response after about six to eight weeks, that's when it's time to try a different drug.
Common side-effects when you start an antidepressant are: dry mouth, nausea, headaches, sleepiness or insomnia, weight gain and constipation or diarrhoea. These effects are usually temporary and they should pass in a few weeks. SSRI's can make you anxious at first and they can sometimes cause longer-term problems with weight gain and with your sex drive. Tricyclics can affect your blood pressure, and MAOI's can have serious and potentially fatal interactions with certain types of foods. If you are prescribed an MAOI, your doctor will tell you which foods to avoid. Always read the patient information leaflet for the full list of side-effects before you take an antidepressant.
6. Suicide Risk
All antidepressants carry an increased risk of suicide. Therefore it's very important that anybody who is starting an antidepressant is carefully monitored by a doctor, and that they report any suicidal thoughts immediately. It's a good idea to keep a list of phone numbers you can call in a crisis, and this should include your doctor or therapist or a crisis team. The risk of suicide associated with antidepressants is a lot higher in children and teenagers.
Generally speaking, it's best to avoid alcohol if you're taking an antidepressant. A few drinks here and there or a glass of wine with your meal is usually okay, but some combinations should not be mixed with alcohol at all. Ever. So ask your doctor first. Large amounts of alcohol also tend to make you more depressed, which can further increase your risk of suicide in the first few weeks of treatment.
8. Physical Dependency
When you've been taking an antidepressant for a while, your brain gets used to the chemical changes the meds cause. Although antidepressants aren't addictive in the true sense of the word, some people experience withdrawal symptoms when they stop taking their medication especially if it's an SSRI, and even more so if you stop taking them abruptly. Withdrawal from reuptake inhibitors can cause severe fatigue, headaches, nausea, vomiting, chills, dizziness, shaking or tremors, insomnia, electric-shock like sensations, vertigo, confusion and suicidal thoughts, plus "brain shivers". These symptoms are collectively known as SSRI Discontinuation Syndrome, but multiple reuptake inhibitors which affect serotonin can also cause this. Don't try to come off your medication on your own. You need to gradually reduce your dose over time to avoid withdrawal effects. Also, some drugs leave the body very quickly so even if you only miss one dose you can experience withdrawal symptoms. It's important to take your meds at the same time every day (or however often your psychiatrist or pharmacist told you to). Getting a pill organiser is a good idea.
9. Sometimes They Stop Working
SSRI's and other reuptake inhibitors can work really well at first and then suddenly stop working. It's known as the 'poop-out' effect. I kid you not, that's what doctors call it. It usually just means you need to switch to another medication in the same class, so don't panic if you find your medication suddenly stops working. Luckily, if you take a break from an antidepressant then start taking it again, it will often work as well as it did when you took it the first time. So if you find two SSRI's that work well for you, but they tend to quit working after a while, you can cycle between the two of them for as long as you need to.
10. Antidepressants Are Not A Cure
For people with severe depression, medication can be a very important part of treatment. It can be the difference between being completely incapacitated, and being able to engage in therapy, being able to go for a walk etc. But antidepressants aren't a magic cure. They don't suddenly make everything okay. Severe mental illness can't be fixed overnight. It usually takes months or even years of treatment to reach some sort of stability where you can get back to your life as it was before you became ill. And non-drug treatments are just as important for people who take medication as they are for those who don't. Doctors, patients, friends, family etc often expect medication to make the problem go away straight away. Some people will even wonder why you can't just "snap out of it" already. It doesn't work like that. Recovering from a serious depressive illness is like recovering from major surgery. It takes time, and the right treatment.
Just a reminder: I'm not a doctor and this is not a replacement for proper medical advice. You should always consult the patient information leaflet for a medication before taking it.