Even after a well-rested night, if you wake up feeling lightheaded and sleepy, there could be various underlying causes. In general, dehydration, standing up for a long time, especially in hot weather, and stress can make you fatigued. However, that's not always the case, especially if you have just woken up from a good night's sleep.
In an interaction with the OnlyMyHealth team, Dr Farah Ingale, Director-Internal Medicine, Fortis Hiranandani Hospital, Vashi, shares possible causes and signs when you should seek medical advice.
Also Read: Lightheadedness: Home Remedies To Stop Everything Around You Moving
What Causes Lightheadedness And Sleepiness After Waking Up?
Morning lightheadedness and sleepiness can be caused by multiple health reasons, like:
Orthostatic hypertension
Also called postural hypotension, orthostatic hypotension is characterised by a sudden drop in blood pressure levels that occurs when a person stands up from a supine position.
Sleep apnoea
Sleep apnoea is a sleep disorder characterised by pauses in breathing during sleep. This can have neurological implications like morning grogginess, headaches, and fatigue. In addition, other sleep issues, including insomnia, can lead to morning lightheadedness and sleepiness, as it creates difficulty in sleeping, resulting in poor quality of sleep, and also migraines, says Dr Ingale.
Endocrine conditions like diabetes
According to Medical News Today, blood sugar fluctuations at night can cause morning dizziness. As per the health website, it can be a sign of low blood sugar, or hypoglycemia, which usually occurs when people either take too much insulin, skip meals, indulge in intense physical activity, or drink too much alcohol.
Hypothyroidism and adrenal insufficiency
Hypothyroidism and adrenal insufficiency can both cause low cortisol levels, which can lead to symptoms like fatigue, muscle weakness, low blood pressure, mood swings, and difficulty concentrating. Some people may even feel weak and lightheaded in the morning when they wake up.
Anaemia or nutritional deficiencies
Anaemia is a blood disorder that occurs due to low iron stores in the body, leading to low Red Blood Cells (RBCs) and haemoglobin in the body. This insufficiency reduces your blood's ability to carry oxygen to your body's tissues, including the brain, leading to symptoms such as lightheadedness.
Also Read: Experiencing lightheadedness? Know the 5 potential reasons behind it
Is It Because Of A Sleep Disorder?
According to Dr Ingale, poor sleep quality and sleep disorders can play a significant role in causing morning lightheadedness and drowsiness.
She explains, "Disrupted sleep patterns, such as fragmented sleep or an imbalance in sleep stages (like reduced REM sleep), can contribute to this. Additionally, decreased oxygen levels and reduced blood flow can also be factors. Sleeping in an uncomfortable position that restricts blood flow to the brain may further exacerbate these issues."
Role Of Hydration And Diet
It is important to note that your dietary choices and hydration levels before bedtime can affect how you feel in the morning.
Dr Ingale states that consuming caffeine or nicotine close to bedtime can cause grogginess in the morning and also affect the quality of sleep. Heavy meals consumed late at night or close to bedtime can also cause heaviness, bloating, abdominal discomfort, and acid reflux, making it difficult to sleep. Moreover, consuming food with a high carbohydrate or sugar content at night can spike blood sugar levels, which is usually followed by a crash and morning fatigue.
Dehydration is another cause of morning dizziness. Experts advise that adults aim to drink around 8 glasses (approximately 2 litres) of water per day to prevent dehydration. However, Dr Ingale also warns of overhydration or drinking too much water, as it can cause frequent urination at night and cause disturbance in your sleep.
When To Seek Medical Attention
Remember, if you experience persistent lightheadedness, fatigue, and morning grogginess, which especially interferes with your daily routine, you should consult your doctor.
Sudden changes in your vision, hearing, numbness or weakness, heart palpitations, and chest discomfort can be a red flag, and you need to consult a doctor at the earliest, Dr Ingale advises.