How Long Should I Take Antidepressants? How Much? How Safe?

In many ways, depressive illness is like cancer. The longer it takes to get the illness under control, the more chance the illness has had to dig itself into your body and sow the seeds for a later relapse.

Research has shown that more than 50% of episodes of depressive illness will return at some stage in a person’s life, typically at times of stress, or at times of physical ill health.

Research has also shown that a person who has had two episodes of depressive illness, has a 75% chance of having another episode and people who have had three episodes of depressive illness, have an almost 100% chance of having a further episode in their lifetime.

Based on the above research findings, the following is the standard advice about taking antidepressants.

First episode of depressive illness

Formal research has been able to show that taking antidepressants for six to eight months from the time you have recovered is statistically safer than stopping antidepressants at any earlier time than this.

It does seem strange to many people to be still taking antidepressants, when their symptoms have disappeared. However, the best comparison is that it is like keeping a plaster cast on a broken leg, even when the pain has disappeared. We all accept that it takes some time for our bones to knit themselves back together again, to be able to function normally. Similarly, it takes some time for our chemistry to knit itself back together, to be able to function normally without the protection of antidepressants.

However, six to eight months is not a cast iron guarantee of your illness remaining at bay. The longer the illness has been present before being brought under control, the more risk of recurrence within a short period of time, just like cancer. Accordingly, although there is no definite scientific proof one way or the other, many experienced clinicians advise people to continue antidepressants for as long as they have been ill before successful treatment of their illness. Accordingly, this may mean anywhere between six months and two years, depending on the duration of your symptoms before a successful treatment was found.

Second episode of depressive illness

The standard advice is that patients should continue antidepressants for two years after having had a second episode of depressive illness.

Three or more episodes of depressive illness

The standard advice is that you should take antidepressants for the rest of your life, to prevent the almost inevitable return of depressive illness otherwise. If you had life threatening or severely disabling cancer, you would understand the need to continuously take chemotherapy, to prevent return of your symptoms. At least, antidepressants do not have the unpleasant side effects associated with chemotherapy. There are at present no known problems with taking antidepressants for very many years and antidepressants are not addictive.

Can I reduce my dose of antidepressants when I feel better?

You would not reduce your dose of chemotherapy if you had cancer, understanding that the more medication you can tolerate, the more your illness is being eradicated and prevented from returning.

Depressive illness is a stress-induced phenomenon and antidepressants are a coat of armour against the stresses of life. In a battle, you would want to carry with you as thick a coat of armour as you could tolerate, provided you were not being made too exhausted by carrying it around.

The only way you will know you are taking too little protection is when the illness gets you again.

Need to adjust dosage of antidepressants

The above paragraph describes the ideal situation, as described in textbooks of psychiatry, namely that you find a dose of antidepressants which has eradicated your symptoms and you take this same dose for many months or years.

However, in my experience, the above scenario can rarely apply. When people are under stress, their symptoms of depression tend to slowly creep back and it is necessary to increase the antidepressant dosage slightly to compensate. Typical early symptoms of depression returning are difficulty thinking clearly, difficulty with memory, reduction in sexual interest, general fatigue and lack of motivation.

In contrast, when life is not so stressful, or when the antidepressants have eventually eradicated your depression and particularly the accompanying anxiety, many people find they start to feel very tired and flat. They are sometimes told the antidepressant must be losing its effect and that they should change antidepressants or increase the dosage. For some antidepressants, this has been described as the “therapeutic window” of that medication. In fact, in my experience, all that is happening in very many cases is that the medication has proved to be too strong for the few remaining symptoms. The person is now being over-sedated by the powerful antidepressant and all that is needed is to reduce the dose of the antidepressant.

Typical symptoms of being over-medicated are feeling tired, yawning a lot, having difficulty thinking of the right word, having difficulty saying the right word, making simple mistakes in spelling or calculations, or falling asleep as soon as one sits in a comfortable position.

With experience, I advise my patients to slightly adjust the doses of their own antidepressant medication, up or down, depending on whether they are experiencing return of depressive symptoms, or being over-medicated.

Are there long term effects from taking antidepressants?

The older antidepressants have been with us since the 1940s, with no evidence of long term problems. The modern generation of antidepressants have been with us since the late 1980s and have been used by hundreds of millions of people, again with no evidence of long term effects over that period of time. Antidepressants have never been shown to be addictive. It therefore seems perfectly safe to take antidepressants on a long-term basis and this is certainly safer than the risks of severe disability or death due to depressive illness.

Alternative to continuous antidepressant medication

You may be reluctant to follow the advice about taking medication on a daily basis for months or years. The alternative approach is to try to detect, in its early stages, the return of your depressive illness and be alert for the symptoms which are particularly significant in your individual case. Tiredness, poor memory and concentration, reduced motivation and reduced sexual interest are the normal early indicators for most people.

In fact, it is probably a very worthwhile exercise to write yourself a brief letter reminding yourself of how well you are now and listing the symptoms you had when depressed. Otherwise, the risk is that you will soon forget the symptoms, especially their early manifestations and you will therefore not recognise the illness returning, until it is too late.

It is also very useful to ask your partner, family or friends to tell you if they think you are becoming ill again.

Important Disclaimer: This site is medical information only and is not to be taken as diagnosis, advice or treatment, which can only be decided by your own doctor.