SAD - Treating seasonal affective disorder

Seasonal affective disorder (SAD) can usually be effectively treated using various treatments, including cognitive behavioural therapy, antidepressants and light therapy.

Depending on the nature and severity of your symptoms, your GP will recommend the most suitable treatment option for you. This may involve using a combination of treatments to get the best results.

NICE recommendations

The National Institute for Health and Care Excellence (NICE) recommends that SAD should be treated in the same way as other types of depression.

This includes using talking treatments such as cognitive behavioural therapy (CBT) or medication such as antidepressants.

Light therapy is also a popular treatment for SAD. However, there's no strong evidence to support the long-term benefits of using light therapy to treat the condition, although research does suggest that it may have a positive short-term effect.

See NICE guidance about the treatment and management of depression in adults.

Psychosocial treatments

Psychosocial treatments focus on both psychological aspects (how your brain functions) and social aspects (how you interact with others). Some possible psychosocial treatments are described below.

Cognitive behavioural therapy

Cognitive behavioural therapy (CBT) starts with the idea that the way we think and behave may affect the way we feel. Changing the way you think about situations and what you do about them can help you feel better.

If you have CBT, you'll have a number of sessions with a specially trained therapist, usually over several weeks or months. Your programme could be:

an individual programme of self-help
a programme designed for you and your partner (if your depression is affecting your relationship)
a group programme that you complete with other people in a similar situation
a computer-based CBT programme that's tailored to your needs and supported by a trained therapist

Counselling and psychodynamic psychotherapy

Counselling is another type of talking therapy that involves talking to a trained counsellor about your worries and problems.

During psychodynamic psychotherapy you discuss how you feel about yourself and others and talk about experiences in your past.

The aim of the sessions is to find out whether anything in your past is affecting how you feel today.

Antidepressants

Antidepressants are often prescribed to treat depression and are also sometimes used to treat SAD when the symptoms are severe.

Selective serotonin reuptake inhibitors (SSRIs) are the preferred type of antidepressants for treating SAD. They increase the level of the hormone serotonin in your brain, which helps lift your mood.

If you're prescribed antidepressants, you should be aware that:

it can take between four and six weeks for the medication to take full effect
you should take the medication as prescribed and continue taking it even if you start to feel better
some antidepressants have side effects and may interact with other types of medication you're taking

An upset stomach is the most common side effect of antidepressants. See the information leaflet that comes with your medication for a full list of possible side effects.

There's limited evidence to suggest that antidepressants are effective in treating SAD. They're thought to be most effective if taken at the start of winter before symptoms appear, and continued until spring.

Light therapy

For some people with SAD, using light therapy can help improve their mood considerably. It involves sitting in front of or beneath a light box.

Light boxes are special lamps that come in a variety of designs, including desk lamps and wall-mounted fixtures. They produce a very bright light. Light intensity is measured in lux – the higher lux, the brighter the light.

Before using a light box to treat SAD you should check the manufacturer's information and instructions regarding:

whether the product is suitable for treating SAD
the light intensity you should be using
the recommended length of time you need to sit in front of the light

Make sure that you choose a light box that is medically proven to treat SAD and produced by a fully certified manufacturer. The Seasonal Affective Disorder Association can provide you with a list of recommended manufacturers.

Very bright light may not be suitable if you:

have an eye condition or eye damage that makes your eyes particularly sensitive to light
have a condition that makes your skin particularly sensitive to light, such as systemic lupus erythematosus
are taking medication that increases your sensitivity to light, such as certain antibiotics, anti-inflammatories, anti-psychotics or the herbal supplement St. John's Wort
have skin cancer

Speak to your GP if you're unsure about the suitability of a particular product.

How light therapy works

Light therapy is thought to work by simulating the sunlight that's missing during the darker winter months.

The additional light encourages your brain to reduce the production of melatonin (the hormone that makes you sleepy) and increase the production of serotonin (the hormone that affects your mood).

Altering the levels of melatonin and serotonin that are released into your body during the winter months can help ease your symptoms of SAD.

However, this is based on the assumption that the condition is caused by a lack of light and the effect that this has on the hormones that are released in your brain.

Research into light therapy

There's mixed evidence regarding the overall effectiveness of light therapy. It's difficult to compare the research that's been carried out in this area because a variety of light sources were used and clinical trials (medical tests) were often conducted over short periods of time.

However, several studies have concluded that light therapy is effective, particularly if it's used first thing in the morning.

It's thought that light therapy is best for producing short-term results. This may mean that it will help relieve your symptoms, but you'll still be affected by SAD next winter.

Side effects of light therapy

It's rare for people using light therapy to have side effects. However, in rare cases you may experience:

mild agitation or irritability
headaches
sleeping problems (avoid using light therapy during the late evening)

Visit your GP if you experience any side effects while using light therapy.