Seasonal affective disorder treatment at Castle Health

Seasonal affective disorder (SAD) is a type of depression triggered by seasonal change, most commonly in autumn and winter when there is less natural daylight. It affects around 2 million people in the UK and 12 million across Northern Europe, and it’s more common in places farther north where there is less sunlight. At Castle Health, we offer SAD treatment across the UK and Europe, helping people understand their symptoms and manage them year-round.

What is seasonal affective disorder (SAD)?

What makes SAD different from other types of depression is that the symptoms tend to arrive at the same time each year and ease as the seasons change.

For most people, low mood sets in during autumn and continues through the winter months. A smaller number of people experience symptoms in spring or summer instead, though this is less common.

SAD is a recognised clinical condition and a specific form of depression. The UK ranks among the top five countries most affected by winter depression globally, and in Scotland, where winters can be long and overcast for months at a time, many people experience the effects of reduced daylight directly.

What is the cause of seasonal affective disorder?

SAD is linked to the effect that reduced daylight has on the brain and body. The most common causes include:

• Less sunlight, which can disrupt the body’s internal clock
• Changes in melatonin, a hormone that affects sleep
• Lower serotonin levels, which can affect mood
• Disrupted routines, as shorter days can mean less time outdoors and less activity.

People who’ve experienced depression before may be more likely to develop SAD.

What are the symptoms and warning signs of seasonal affective disorder?

SAD can affect how you feel, how you sleep, and how much energy you have. Common symptoms include:

• Continued low mood
• Loss of interest in things you usually enjoy
• Low energy and tiredness
• Sleeping more than usual
• Difficulty concentrating
• Changes in appetite, often a craving for carbohydrates
• Feeling withdrawn or hopeless

If you notice these symptoms returning each year as the days get shorter, our team can talk you through what might help.

What is the best treatment for seasonal affective disorder?

Seasonal affective disorder light therapy

Light therapy is often the first treatment recommended for seasonal depression treatment. It involves sitting near a light box that produces light similar to natural daylight, usually for around 20 to 30 minutes each morning.

It may help by:

• Resetting your sleep and wake cycle
• Increasing your energy and alertness during the day
• Improving low mood caused by reduced daylight
• Supporting a more regular daily routine

Light therapy is often used alongside other treatments for seasonal affective disorder.

Psychological therapy for SAD

Seasonal affective disorder therapy, especially Cognitive Behavioural Therapy (CBT), can help you understand how reduced daylight and shorter days are affecting your thoughts and actions. It may involve:

• Identifying how your mood changes between autumn and spring each year
• Working through negative thoughts that become more frequent in winter
• Building daily routines that help maintain your energy and motivation
• Planning practical steps for the months you find most difficult.

Instead of waiting until symptoms become severe, therapy gives you tools to use before and during the months you find difficult. 

Medication for SAD

For some people, medication is part of SAD treatment. SSRIs may be prescribed after a full assessment with a registered mental health professional and are usually reviewed regularly, often alongside therapy.

Which clinics offer specialised seasonal affective disorder treatment in the UK?

Treatment is available through the NHS and through private providers. Whether you access support through your GP or through other mental health services, it’s worth seeking help from clinicians who have specific experience in seasonal depression and mood conditions.

Some people use the NHS, while others choose private SAD treatment for faster access to a specialist.

Seasonal affective disorder treatment at Castle Health

At Castle Health, we offer SAD treatment at our locations across the UK and Europe. We start with a psychiatric assessment, which gives our clinical team a chance to understand how SAD is affecting you specifically. From there, we’ll work with you to find the right combination of therapy, outpatient treatment, and medication, if needed. Our teams have over 35 years of experience with depression and mental health conditions, and where seasonal depression is connected to addiction or other difficulties, we can make sure both are looked after together. If winter is a difficult time for you, we’re here to help. Outpatient SAD treatment is also available at Castle Craig in Scotland, where our specialist team provides assessment, therapy, and ongoing support.

Frequently asked questions

Does SAD cause anxiety?

SAD can make anxiety worse. When mood and energy drop in autumn and winter, worries can feel harder to manage, and anxiety symptoms can become more noticeable. For some people, anxiety is a separate condition that exists alongside SAD. In these cases, the seasonal change makes anxiety worse, but it’s not the original cause.

Is SAD a form of bipolar disorder?

SAD is not the same as bipolar disorder. SAD is a type of depression that gets worse in autumn and winter and improves in spring. Bipolar disorder involves shifts between low and high moods that happen throughout the year, not just in winter. Some people with bipolar disorder do notice that their mood gets worse in winter, but the two conditions are diagnosed and treated differently.

Who does SAD impact?

SAD can affect people of all ages. It’s more common in people who live further north, where winters are darker and longer, and more likely in people who have experienced depression before. SAD treatment UK-wide is available through the NHS and through private providers.

When is a person more likely to develop SAD?

Symptoms most often start between October and December, when the days get noticeably shorter and darker. For most people, symptoms begin to improve in March or April when daylight hours increase again.