Tiredness and low energy
Feeling tired after exertion or a short night is normal and resolves with rest. This is about something else: having no energy all the time, finding that…
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Medicines commonly prescribed for Tiredness and low energy
For informational purposes only. Always consult a doctor before taking any medication.
Dosage form: MODIFIED-RELEASE TABLET, 105 mgActive substance: ferrous sulfateManufacturer: Teofarma S.R.L.Prescription requiredDosage form: INJECTABLE, 1 mg/mlActive substance: hydroxocobalaminManufacturer: Laboratorios Basi Industria Farmaceutica S.A.Prescription requiredDosage form: INJECTABLE, 10 mg hydroxocobalamin/2 mlActive substance: hydroxocobalaminManufacturer: Aristo Pharma Iberia S.L.Prescription required
Feeling tired after exertion or a short night is normal and resolves with rest. This is about something else: having no energy all the time, finding that rest does not restore it, and needing disproportionate effort for ordinary tasks. It is one of the most common complaints and one of the most underestimated: there are concrete causes behind it, and most of them show up on simple blood tests.
Tiredness or sleepiness?
This is the first thing worth separating, because it decides where to look.
- tiredness — no energy, but you cannot fall asleep during the day; lying down does not refresh you. More often linked to depression, anaemia, thyroid disease and chronic illness;
- sleepiness — you genuinely fall asleep if you sit down somewhere quiet. More often linked to insufficient sleep, sleep apnoea and narcolepsy.
Common causes
- not enough sleep and irregular hours — the most common cause and the least acknowledged;
- sleep apnoea — snoring with pauses in breathing; the person sleeps eight hours and still wakes exhausted;
- depression and anxiety disorders — fatigue is part of the definition of depression and is often its first sign;
- anaemia and iron deficiency — very common in women; tiredness appears even before anaemia, with low ferritin;
- thyroid disease;
- vitamin B12 and vitamin D deficiency;
- diabetes;
- infections and the recovery period afterwards, including prolonged states following viral illness;
- chronic conditions — heart, lung, kidney and liver disease, inflammatory bowel disease, rheumatic conditions, cancer;
- medication — antihistamines, sleeping tablets, blood pressure drugs, antidepressants, statins, opioids;
- alcohol — it destroys the second half of the night;
- pregnancy, especially the first trimester;
- perimenopause;
- overload and burnout — caring for an unwell relative, shift work, small children;
- chronic fatigue syndrome — a diagnosis made after excluding everything else.
What you can do
- sleep first: 7–9 hours, going to bed and getting up at the same time, weekends included;
- morning light and daytime activity;
- exercise: when you are exhausted it feels impossible, yet it is exactly what helps most. Start small, with a short daily walk;
- regular meals with enough protein and no long gaps;
- caffeine only in the first half of the day; more than three or four cups worsens sleep and increases fatigue;
- limit alcohol: it does not help you recover;
- drink enough water;
- reduce your load where you can, and allow yourself to leave some things undone;
- if you nap, keep it to 20 minutes and before 3 pm;
- keep a two-week diary of sleep, activity and how you feel by time of day. It helps the doctor enormously.
When to see a doctor
- the tiredness has lasted more than 2–4 weeks despite adequate sleep and rest;
- it is stopping you working or living normally;
- it comes with weight loss, fever, night sweats or enlarged lymph nodes;
- you have developed breathlessness, chest pain, palpitations or swelling;
- you have heavy periods or blood in your stool — there may be unrecognised blood loss;
- your mood has dropped, you have lost interest in things you used to enjoy, or you have thoughts of harming yourself — seek help straight away;
- you snore with pauses in breathing and feel sleepy during the day;
- the tiredness started after beginning a medicine;
- you have muscle and joint pain, a rash, hair loss, or dry mouth and eyes;
- it started after an infection and has lasted months.
What happens at the appointment
The doctor will ask in detail about sleep, mood, workload, diet, medication, alcohol and periods. The usual tests are: full blood count, ferritin, thyroid function, glucose and HbA1c, vitamin B12, vitamin D, liver and kidney function, inflammatory markers and, where indicated, coeliac screening and other investigations.
Normal results are not a dead end: they mean the cause is more likely to lie in sleep, mood or workload, and that is where the work needs to happen. That result is useful too.
Treatment
There is no single remedy "for tiredness" — the cause is treated, and the effect is usually noticeable: replacing iron and B12, correcting thyroid function, treating depression and anxiety, CPAP for sleep apnoea, a medication review, treating the underlying chronic condition. Chronic fatigue syndrome is handled differently: careful, gradual pacing of activity and a deliberate refusal to increase it sharply, since that makes things worse.
Common questions
Will vitamins help? Only if a deficiency is confirmed. "Energy" supplements without a deficiency do nothing.
Should I just rest more? If you are sleep-deprived, yes. But if tiredness persists despite good sleep, more rest will not help and movement will.
Could it just be my age? Age does not explain persistent fatigue. The cause is worth looking for.
What if my tests come back normal? That is common and it is good news. Attention then turns to sleep, mood, workload and physical activity.
Online consultation
In an online consultation the doctor helps you separate tiredness from sleepiness, reviews your sleep, mood and workload, checks the link with your medication, arranges the necessary tests and explains what to do if they come back normal.
This material is for information only and does not replace a medical consultation.
Consult with a doctor about Tiredness and low energy
Discuss your symptoms and possible next steps with a doctor online.
Medically reviewed by
Reviewed on Jul 19, 2026
Online doctors for Tiredness and low energy
Discuss your symptoms and possible next steps for Tiredness and low energy with a doctor online.
