Seasonal Affective Disorder (SAD)

Seasonal affective disorder (or SAD), is a type of depression that occurs during the same season every year. It is a mood disorder affecting people who have normal mental health throughout most of the year, but experience symptoms of depression in a particular season, usually winter (but may also be any of the others). This disorder occurs only during a given time of the year and you go back to being normal throughout the rest of the year.

Anyone can get SAD, but it's more common in women than men. It is also more likely to affect you if you live far from the equator, where winter daylight hours are very short. You are more likely to experience SAD if you are between the ages of fifteen and fifty five. The risk of getting SAD is low amongst older people. You are also at a higher risk of having SAD if you have a close relative who suffers from the same disease. It is sometimes also referred to as winter depression, summertime sadness, or seasonal depression.

The exact cause of seasonal affective disorder is not known but experts believe that it may be caused by a lack of sunlight which upsets your body’s natural pattern of sleeping and waking up. This causes problems with the production of serotonin, a chemical found in your body which sends signals between nerves and affects your mood.​​

Signs and symptoms of seasonal affective disorder appear at the same time each year, and include:

  • Feelings of sadness, tearfulness or hopelessness

  • Weight gain and food cravings 

  • Weight loss

  • Loss of interest in normal activities

  • Sleep disturbances such as excessive sleep or insomnia

  • Tiredness and lack of energy

  • Irritability

  • Difficulty in concentration​​

If you are experiencing feelings of helplessness, loneliness, irritability or tiredness during a particular time of the year, do not ignore these symptoms as “seasonal blues” and make it a point to visit your doctor. You can obtain additional information and medical advice from the doctors working with the Mind and Brain Service Line​ at The Aga Khan University Hospital.​
Your time with your doctor may be limited, so make sure to prepare for your visit beforehand. Here​ are some tips to help get you started.​

The symptoms of seasonal affective disorder largely overlap with the symptoms of other types of depression​. Your doctor will take down a detailed family and medical history, particularly asking if any other member of your family suffers from SAD. He/she will also ask details about your symptoms, including whether you have been depressed at the same time for two or more years and have gotten better when the season changed. 

Your doctor may also order blood tests to examine your thyroid function, as sometimes these symptoms are known to be caused by low thyroid. You should be prepared to discuss your symptoms, thoughts, feelings and behaviour. You may also have to fill out a detailed questionnaire to answer these questions.​​

Treatment options for seasonal depressive disorder include: 

  • Light therapy: this involves sitting in front of a fluorescent light between half an hour to two hours a day, depending on how strong the light is. You can do this while continuing your normal activities such as eating, reading or watching TV. Sometimes a dim light will be placed in your room, which will get progressively lighter, stimulating the effect of dawn. It is important to stick with this treatment until your doctor says it’s okay to stop, usually until the season changes.

  • Anti-depressants: your doctor may prescribe anti-depressants such as selective serotonin reuptake inhibitors. These medications are safer and generally cause fewer side effects than other types of antidepressants. You must never stop taking antidepressants without talking to your doctor first. Stopping treatment abruptly or missing several doses can cause withdrawal symptoms, and quitting suddenly may cause a sudden worsening of depression. 

  • Counselling: this will helps you to,

    • ​Develop positive interactions with others

    • Find better ways to cope and solve problems

    • Identify issues that contribute to your depression 

    • Regain control of your life and help ease depression symptoms

    • Develop the ability to tolerate and accept distress using healthier behaviour.​

The Aga Khan University Hospital offers various support services to help with managing or recovering from the disease or condition. These include but are not limited to nutrition, physiotherapy, rehabilitation, specialized clinics and some patient support groups. Your doctor or nurse will advise you accordingly.

The Aga Khan University Hospital offers financial assistance to those who are in need and fulfil the eligibility criteria. For further information, you can contact the Patient Welfare Department. You can find the contact number of the Patient Welfare Department in the ‘Important Numbers’ section on the website homepage.​

The financial counselling staff is available during office hours, at the main PBSD (Patient Business Services Department), to answer your financial queries on treatments’ costs and authorize admissions on partial deposit as per hospital policies allow. The financial counsellor in the emergency room is open 24/7. You can find the contact number of the Patient Business Services in the ‘Important Numbers’ section on the website homepage.​​

Your doctor and or nurse will give you specific instructions about the prescribed medication. Please ensure that you take or use the prescribed medicine as advised. It can be dangerous to your health if you self-prescribe. Please inform the doctor or nurse beforehand if you have experienced any adverse reactions to any medications in the past. If you experience any symptoms of drug poisoning, overdose or severe reaction please contact the Pharmacy Service at The Aga Khan University Hospital immediately. You can find the contact number of the Pharmacy Services in the ‘Important Numbers’ section on the website homepage.​


The information provided on our website is for educational purposes and not intended to be a substitute for medical advice, diagnosis or treatment. You should always seek the advice of your doctor or other healthcare professional provider.