Feeling tired all the time is one of the most common reasons people contact a GP. For some, it is mild but persistent. For others, it is overwhelming and affects work, family life and motivation.
While busy lives and poor sleep can certainly contribute, ongoing fatigue should not automatically be dismissed as “just stress” or “just getting older”. There are many medical and physiological reasons why you may be feeling exhausted.
Why Persistent Fatigue Matters
Occasional tiredness is normal, particularly after a busy week or a poor night’s sleep. However, persistent or worsening fatigue is not something you simply have to live with.
Fatigue can be an early sign that something in the body is out of balance. Early discussion with a GP can lead to reassurance, investigation and appropriate treatment before symptoms worsen.
Common Medical Causes of Fatigue
Fatigue rarely has a single cause. Often, several factors combine to leave you feeling drained.
Iron Deficiency and Anaemia
Low iron levels are common, particularly in women with heavy periods or those with dietary insufficiency. Symptoms may include fatigue, breathlessness, dizziness, headaches, palpitations and poor exercise tolerance.
Thyroid Disorders
An underactive thyroid (hypothyroidism) can cause fatigue, weight gain, cold intolerance, low mood, hair thinning and brain fog. This condition is more common than many people realise and is easily identified through blood tests.
Vitamin B12 Deficiency
Low B12 levels can lead to fatigue, pins and needles, numbness, poor concentration and memory problems. Vegetarians, vegans and older adults are at higher risk.
Vitamin D Deficiency
Despite living on the sunny Costa del Sol, vitamin D deficiency remains surprisingly common. It is associated with muscle aches, joint pain, low mood and fatigue.
Quick Tip: Even with regular sun exposure, factors like sunscreen use, time spent indoors and skin type can affect vitamin D levels. If you are experiencing unexplained fatigue, it is worth having your levels checked.
Hormonal Changes
Perimenopause, menopause and other hormonal shifts can contribute to fatigue, poor sleep and low energy. These changes often creep up gradually and may not be immediately recognised as hormonal.
Sleep Disorders
Poor sleep quality, insomnia or conditions like sleep apnoea can cause significant daytime fatigue, even when you feel you have slept enough hours.
Mental Health Factors
Anxiety, low mood and chronic stress can be physically exhausting. The body’s stress response uses considerable energy, and prolonged activation can leave you depleted.
Blood Sugar Dysregulation
Fluctuating blood sugar levels, whether from diet, prediabetes or other metabolic issues, can contribute to energy crashes and persistent fatigue throughout the day.
Medication Side Effects
Some medications, including certain blood pressure tablets, antihistamines and antidepressants, can contribute to tiredness as a side effect.
Why Proper Assessment Matters
Assuming fatigue is “just lifestyle” can delay diagnosis of treatable conditions. Many causes of fatigue respond well to treatment once identified.
What a GP Considers During Assessment
- Symptom pattern and severity
- Duration of fatigue
- Medical history
- Current medications
- Lifestyle factors including sleep, diet and activity
- Family history of relevant conditions
What Can Be Managed Through Online Consultations
- Initial assessment and history taking
- Blood test requests where appropriate
- Review of results with clear explanations
- Management planning and lifestyle advice
- Follow-up appointments to monitor progress
Quick Tip: Before your consultation, keep a brief note of when your fatigue is worst, any other symptoms you have noticed, and what you have already tried. This helps make the most of your appointment time.
If your fatigue is accompanied by back pain, neck pain or general muscle aches, our physiotherapy team can also assess whether physical factors may be contributing to your symptoms.
Frequently Asked Questions
Is fatigue ever normal?
Short-term tiredness after a busy period or poor sleep is normal. Ongoing fatigue that lasts weeks or months, or that significantly affects your daily life, should be assessed by a GP.
Can an online GP arrange blood tests?
Yes. Blood tests can be requested where appropriate to check for common medical causes of fatigue. You would attend a local laboratory to have the samples taken.
What if my blood tests come back normal?
Normal results are still useful. They help rule out serious causes and guide further management. Your GP can then focus on other potential contributors such as sleep quality, stress or lifestyle factors.
Could stress alone be causing my fatigue?
Stress can certainly contribute to fatigue, but physical causes should also be considered and ruled out. Often, stress and physical factors coexist.
Can more than one thing be causing my fatigue?
Yes, this is common. Multiple factors such as low iron, poor sleep and stress often coexist and compound each other. Addressing several contributing factors may be needed for full improvement.
Do I need to be completely exhausted to seek help?
No. Earlier assessment is better. You do not need to wait until fatigue is severe to speak with a GP. Identifying and addressing causes early often leads to quicker improvement.
Will I be taken seriously?
Absolutely. Fatigue is a common and valid reason to seek medical advice. Our doctors will always take all concerns seriously and works with you to find answers.
Taking the First Step
Feeling tired all the time is not something you simply have to accept. An online GP consultation can be a straightforward first step toward understanding why you feel this way and what can be done about it.
If you are ready to explore the causes of your fatigue, contact Costa Health to book an appointment, appointments can also be booked online at