Fatigue and No Energy in Older Adults: Common Causes, Warning Signs That Need a Doctor, and Safe Ways to Rebuild Strength

Fatigue and no energy in older adults should not simply be put down to getting older. There is often a cause that can be found and addressed: drinking too little, eating too little, certain medicines, poor or insufficient sleep, anaemia, thyroid problems, diabetes, an infection without an obvious fever, or depression. The most useful thing a family can do is work out whether the tiredness has come on gradually or suddenly, keep a 7-day record, and take your parent to the doctor. But if weakness comes on suddenly with a drooping face, weakness on one side, slurred speech, confusion or chest pain, call 1669 straight away instead of waiting to see.

Many families describe the same picture. Your father used to walk to the market every morning and water the plants every day. Lately he dozes in front of the TV all afternoon, says he "has no energy, can't be bothered", and eats half a plate. When you ask, he says, "That's what happens when you get old." You are not sure whether to let him rest, buy him vitamins or take him to the doctor. This guide is for families who notice a parent becoming more tired without a recent hospital stay: the common causes, which symptoms cannot wait, what to note down for the doctor, and how to help your parent regain strength safely.

Quick answer

• Fatigue in older adults should not always be seen as part of ageing. Cleveland Clinic in the US lists being over 65 with fatigue as one reason to contact a healthcare provider.
• Common causes that can be assessed: drinking too little, eating too little, some groups of medicines, poor sleep, anaemia, thyroid problems, diabetes, infection, depression, heart or kidney disease, and sitting or lying down all day.
• Fatigue that comes on suddenly, or comes with a drooping face, one-sided weakness, slurred speech, confusion, drowsiness, chest pain, breathlessness or an abnormal heartbeat, means calling 1669.
• Gradual fatigue that continues for several days, with no clear cause, reduced ability to do daily tasks, or weight loss, means seeing a doctor this week.
• Keep a 7-day record before the appointment: sleep, food, drinks, every medicine, bowels and bladder, activity, and any other symptoms.
• Do not buy vitamins, iron or supplements yourself before the cause is known. To rebuild strength, start gentle daily movement once a doctor has checked your parent, and have a physiotherapist assess how much to start with.

1. Is fatigue and lack of energy normal in older adults?

It should not be seen as a normal part of ageing until a doctor has looked for the cause. Older adults may do things more slowly, but being too tired to get up, dozing all day, or no longer managing the usual routine are signs that something in the body has changed. Cleveland Clinic advises contacting a provider when fatigue lasts longer than a few days, starts suddenly, has no clear cause such as a recent illness, or makes daily activities hard, and also if you are over 65 or losing weight. The UK's National Health Service (NHS) advises seeing a GP if you have felt tired for a few weeks and are not sure why.

A difference families can notice is between tiredness that improves with rest and tiredness that does not improve even after a full rest. If it is the second kind, or your parent can no longer do things they used to do alone, such as bathing, dressing or walking to the toilet, do not wait for it to "pass".

If your parent has just come home from hospital and is weak and struggling to walk, the causes and care are different. See weakness in older adults after a hospital stay.

2. What causes fatigue in older adults? 10 common groups of causes

Fatigue in older adults often comes from several causes together, for example drinking too little while taking several medicines. The list below is drawn from Cleveland Clinic and the NHS. It is not for self-diagnosis, but it helps families know what to watch for and what to tell the doctor.

1) Drinking too little

The NHS says older adults are more at risk of dehydration. Signs include dark yellow, strong-smelling urine, passing urine less often than usual, feeling dizzy or lightheaded, tiredness, and a dry mouth, lips and tongue. Many older people do not feel thirsty, or drink less on purpose to avoid getting up for the toilet. If the doctor has limited fluids because of heart or kidney disease, follow the doctor's amount and do not increase it yourself.

2) Eating too little, losing weight

Not getting enough energy and protein leads to low energy and muscle loss. If your parent is eating less or their clothes are getting loose, see poor appetite and eating little in older adults.

3) Medicines

Cleveland Clinic notes that several groups of medicines can cause fatigue, such as some sleeping and anti-anxiety medicines, opioid painkillers, some blood pressure or heart medicines, and over-the-counter antihistamines. Older adults on several medicines, who have just started a new one or had the amount changed, should have a doctor or pharmacist review everything they take. Do not stop any medicine yourself. For organising medicines at home, see a medication system for older adults at home.

4) Too little or poor-quality sleep

Difficulty sleeping, waking often at night, or napping so much in the day that night-time sleep suffers all lead to daytime sleepiness. The NHS advises seeing a GP if someone hears your parent making gasping, snorting or choking noises while asleep, such as snoring that stops and starts, which can be a sign of sleep apnoea.

5) Anaemia

The NHS lists the symptoms of iron deficiency anaemia as tiredness and lack of energy, shortness of breath, noticeable heartbeats (palpitations) and paler than usual skin. One common cause is bleeding in the stomach or intestines, which can be linked to regularly taking anti-inflammatory painkillers. So an older adult who is looking paler needs a doctor to find the cause, not a blood tonic bought at the pharmacy. If you notice black, tarry stools or blood in the stool, see a doctor promptly.

6) Thyroid problems

An underactive thyroid causes marked tiredness, weight gain, feeling the cold more than usual, constipation and low mood. The NHS says symptoms usually develop slowly and worsen over time, which is why they are easily blamed on age. A doctor can check with a blood test.

7) Diabetes, high or low blood sugar

Both poorly controlled diabetes and low blood sugar from medicines can cause fatigue. If your parent checks their blood sugar at home, take the readings to the doctor. In older adults, low blood sugar may not cause obvious shaking or sweating; it can show up as confusion, drowsiness, slow speech, changed behaviour or a fall. If your parent takes diabetes medicine and becomes unusually tired or drowsy, check their blood sugar straight away.

If the reading is low (following Thailand's 2023 clinical practice guideline for diabetes):

1. At 70 mg/dL or below, if your parent is alert and can swallow, give about 15 g of fast-acting sugar, such as 180 ml of fresh orange juice, 180 ml of a regular (not sugar-free) soft drink, or 3 teaspoons of honey.
2. Recheck after 15 minutes. If it is still below 70, give another 15 g.
3. Once better, have them eat their next meal or a snack, and tell the doctor who prescribes the diabetes medicine.
4. If your parent is drowsy, unconscious or cannot swallow, give nothing by mouth and call 1669 immediately.

8) Infection without an obvious fever

Older adults with an infection may not run a high fever as younger people do. The NHS says a urinary tract infection in older or frail people may show up as changes in behaviour, agitation or confusion, leaking urine more than usual, and new shivering, and that a very low temperature below 36°C can also be a sign of infection. If your parent is tired along with these signs, or their temperature is below 36°C, get urgent medical advice today; if they are also confused, drowsy or have difficulty speaking, call 1669 immediately.

9) Mood and depression

Depression in older adults does not always look like sadness. Some people only complain of no energy, a poor appetite, sleeping too little or too much, and losing interest in things they used to enjoy. If no physical cause is found, or your parent has recently been through a loss, such as the death of a partner, moving house or retiring, tell the doctor about it. You can talk to our mental health team through our mental health service. If your parent talks about harming themselves, take them to a doctor immediately.

10) Other long-term conditions, and sitting or lying all day

Cleveland Clinic lists heart disease, heart failure and chronic kidney disease among the causes of fatigue. Sitting or lying down all day also weakens the muscles steadily: the less your parent moves, the less energy they have, and the cycle continues.

3. Gradual versus sudden fatigue: what's the difference?

Fatigue that has built up over several weeks should be assessed by a doctor without waiting for the next routine appointment; bring whatever record you have. Fatigue or weakness that develops within a few hours, especially with symptoms affecting the brain, should always make you think of stroke first.

Fatigue is not the same as weakness. Fatigue is feeling drained all over, wanting to lie down and doing less, yet still being able to lift the arms, sit up or walk when making the effort. Weakness means the muscles genuinely lack strength: one arm cannot be raised, a hand cannot hold things, or your parent cannot stand when they could yesterday. New weakness, especially on one side, means calling 1669 straight away.

Spot a stroke with FAST

The NHS uses the acronym FAST to make it easy to remember:

• F (Face): the face droops on one side; your parent cannot smile evenly.
• A (Arm): they cannot lift both arms and keep them up, because one is weak or numb.
• S (Speech): slurred or confused speech, or trouble finding words.
• T (Time): if you see even one of these signs, call 1669 immediately and note the time symptoms started.

Other symptoms the NHS lists include weakness or numbness down one side of the body, blurred vision or loss of sight in one or both eyes, confusion, dizziness or falling, and a severe headache. Even if the symptoms go away within minutes, your parent still needs hospital care straight away. Do not drive them yourself; call 1669. See how to prepare before calling in an emergency and 1669 plan for older adults.

Other symptoms that cannot wait

Cleveland Clinic advises seeking immediate medical attention for fatigue together with chest, arm or upper back pain, shortness of breath, an unusually fast or slow heartbeat, a pounding, fluttering or irregular heartbeat, headache or vision problems especially after a head injury, nausea, vomiting or abdominal pain, muscle weakness, or thoughts of harming oneself or others.

4. A 7-day symptom record before seeing the doctor: what to note

A 7-day record lets the doctor see what the family sees every day but cannot fully explain in a few minutes in the consulting room. Use one notebook and write a short entry once a day in the evening. You do not need to wait for all 7 days. If symptoms have lasted several weeks, daily tasks are slipping, your parent is losing weight, or there is a worrying new symptom, take whatever record you have to the doctor now.

1. Sleep: bedtime, waking time, how often they woke at night, how long they napped, any snoring or gasping.
2. Food: how much of each plate they finished, any skipped meals, any coughing or choking when swallowing.
3. Drinks: roughly how many glasses of water a day, urine colour, how often they go to the toilet.
4. Every medicine: including shop-bought medicines, vitamins, herbal products, and anything recently started or changed. Take photos of all the packets.
5. Bowels and bladder: which days they opened their bowels, constipation, black stools or blood, burning or more leaking when passing urine.
6. Activity: what they managed alone today, what they used to do but could not, how far they walked.
7. Other symptoms: fever, cough, breathlessness, palpitations, dizziness, paleness, swelling, mood, confusion, weight (weigh once a week) and, if you have devices at home, blood pressure and blood sugar.

Nurse's tip: make the first line of the record "When did the tiredness start, and what changed just before?", for example a new medicine, a cold, or something upsetting. The answer is often the clue the doctor finds most useful.

5. What tests are needed for fatigue? What the doctor may do

The doctor will usually start by taking a history, reviewing medicines and examining your parent, then choose further tests based on what they find. There is no single set of tests for everyone. Cleveland Clinic says a provider may order blood and urine tests, and the NHS gives examples of blood tests to check for anaemia, diabetes and thyroid problems.

How the family can help on the day:

• Bring the 7-day record and all medicines in one bag.
• Bring the person who spends the most time with your parent, because they see the symptoms first-hand.
• Tell the doctor plainly what worries you most, for example: "Dad has dozed all day for 3 weeks, when he used to walk to the market every morning."
• Before leaving, ask: what cause is the doctor thinking of, what other tests are needed, when should we come back if things get worse, and how much can he start moving?

If everyone works and nobody can take your parent to the appointment, our hospital escort service sends a carer who collects your parent from home, stays with them throughout and notes what the doctor says for the family. See hospital escort.

6. Rebuilding an older adult's strength safely at home

Once a doctor has checked your parent and found nothing that needs urgent treatment, appropriate daily movement is an important part of regaining strength, alongside treating whatever cause the doctor finds. The NHS recommends that adults aged 65 and over are physically active every day, even if only lightly, cut down long periods of sitting or lying still, and do activities that improve strength, balance and flexibility on at least 2 days a week. But speak to a doctor first if your parent has not exercised for some time or has medical conditions.

How to start safely

• Get up from the chair regularly through the day and avoid long periods of sitting or lying still: short walks around the house to water plants, fetch something or go to the toilet alone.
• Break activities into short bouts with rests rather than one long session that leaves your parent exhausted.
• Let your parent do what they still can, such as dressing, serving their own food or washing, while you stay close by rather than doing everything for them.
• Have a physiotherapist assess before serious exercise, especially if your parent has fallen, walks unsteadily or has heart disease. The physiotherapist checks leg strength, balance and falls risk and teaches exercises to continue every day.
• Make walkways safe: good lighting, rugs and cables cleared, and non-slip footwear.

Stop straight away if

If your parent has chest pain or tightness, is so breathless they cannot finish a sentence, or faints during exercise, stop immediately and call 1669. Do not wait to see, do not let them keep walking, and do not drive them yourself. For dizziness, palpitations or unusual pain, stop and sit down; if they do not improve, or have any of the symptoms in section 3, call 1669.

7. Fatigue in older adults: what can wait and what cannot. A three-level decision plan

The plan below is drawn from advice by Cleveland Clinic and the NHS and should be used alongside your own judgement. If you are unsure which level applies, choose the more urgent one.

Continue care at home and watch closely

• More tired than usual after extra activity or 1 to 2 nights of poor sleep, and better after rest.
• Still eating and drinking, normal urine colour, managing daily tasks as before.
• What to do next: encourage drinks (if the doctor has limited fluids, follow the doctor's amount), keep regular sleep times, move every day and start the record. If things do not improve within a few days, move to the next level.

Call a nurse for advice today

See a doctor today or within 24 hours

• Fatigue together with more urine leakage, shivering or small changes in behaviour, which may be an infection.
• A temperature below 36°C, or a fever, with increasing tiredness (if confused or drowsy as well, call 1669).
• Dark yellow urine, passing less urine than usual, dry mouth, dizziness.
• Fatigue that is getting worse quickly over a few days.

Book a doctor this week, without waiting for a routine appointment

• Fatigue continuing for more than a few days, with no clear cause, or for several weeks.
• Managing fewer daily tasks alone, walking noticeably more slowly.
• Unintended weight loss, eating less and less.
• Looking paler, palpitations, getting breathless more easily when walking.
• Sleepy all day, loud snoring, gasping or choking noises during sleep.
• More tired after starting or changing a medicine (do not stop it yourself; ask the doctor or pharmacist).

Go to hospital or call 1669 now

• A drooping face, weakness or numbness on one side, slurred speech or sudden loss of vision, even if it has passed.
• Sudden confusion or drowsiness, hard to wake.
• A temperature below 36°C or a fever, together with confusion, drowsiness or difficulty speaking.
• Diabetes with low blood sugar causing drowsiness or inability to swallow, or not improving after sugar.
• Chest pain, arm or upper back pain, breathlessness.
• A very fast or very slow heartbeat, or fainting.
• Fatigue after a knock to the head, with headache or vision problems.
• Black stools or vomiting blood.
• Talking about harming themselves.

Common mistakes families make

• Thinking "that's just old age". Treatable causes such as anaemia, thyroid problems or medicines are left for too long. Fix: get your parent checked when it lasts more than a few days or daily tasks are slipping.
• Buying vitamins, blood tonics or supplements yourself. They may not match the cause, may mask symptoms or interact with current medicines. Fix: let the doctor find the cause first, then use what the doctor or pharmacist advises.
• Keeping your parent in bed all day to "save energy". Muscles weaken further and walking gets harder. Fix: gentle daily movement as the doctor and physiotherapist advise.
• Stopping a medicine because you think it causes tiredness. The original condition may flare. Fix: take all medicines to the doctor or pharmacist for review.
• Waiting with one-sided weakness or slurred speech "in case it passes". The most important time in a stroke is lost. Fix: call 1669 straight away, even if symptoms have improved.
• Going to the doctor empty-handed. Symptoms get only half told. Fix: bring the 7-day record and a bag with every medicine.

When to bring in professional help

Most families can watch for symptoms and keep a record themselves. But if nobody is home during the day, nobody can take your parent to the doctor, or the doctor has checked your parent and you want to help them regain strength safely, a professional team can share the load. KIN HomeCare services that fit this situation:

• Home physiotherapy: a physiotherapist assesses muscle strength, balance and falls risk, then sets up a programme to continue every day. 1,800 baht per session, first session 1,500 baht until 31 December 2026, 10-session course 15,000 baht. Available in Bangkok and surrounding provinces only. See home physiotherapy.
• Registered nurse home visit: checks vital signs, assesses symptoms, reviews eating, drinking and current medicines, and advises how soon to see a doctor. 1,800 baht per visit.
• Hospital escort: a carer collects your parent from home, stays with them throughout and brings them back, 1,800 baht for 8 hours, 200 baht for each extra hour. Transport is charged separately; KIN's ambulance starts at 2,000 baht depending on distance.
• Caregivers (nursing assistants) at home: encourage drinks, prepare meals, walk with your parent and keep a daily symptom record for the family. A 12-hour shift is 1,800 baht per day (minimum 3 days for daily booking).

Every service can issue receipts and medical certificates for insurance claims, subject to your policy's conditions. Our team does not diagnose illness; if we see signs that need a doctor, we tell the family straight away.

Frequently asked questions

What causes fatigue and lack of energy in older adults?

There are many possible causes, and they often occur together. Common ones are drinking too little, eating too little, some groups of medicines, poor sleep, anaemia, thyroid problems, diabetes, infection, depression, heart or kidney disease, and sitting or lying down all day. A doctor should look for the cause rather than the family guessing.

My parent is sleepy all day and keeps dozing off. Is that abnormal?

If it is new or clearly getting worse, look for a cause, such as poor sleep at night, sedating medicines, sleep apnoea, anaemia or thyroid problems. But if your parent is so drowsy they are hard to wake, or becomes confused suddenly, call 1669.

My parent looks pale and tired. Should they take a blood tonic?

Not without seeing a doctor. Anaemia in older adults needs its cause found first, because it is sometimes due to bleeding in the digestive tract. Let the doctor do a blood test and prescribe treatment that fits the cause. If stools are black or contain blood, go to hospital promptly.

What tests are needed for fatigue?

It depends on the history and examination. Doctors usually begin with questions, a medicine review and possibly blood and urine tests, for example for anaemia, blood sugar and thyroid function. Bringing the 7-day record and all medicines helps the doctor choose the right tests.

My parent has diabetes, feels tired and the blood sugar reading is low. What should I do?

At 70 mg/dL or below, if your parent is alert and can swallow, give about 15 g of fast-acting sugar and recheck after 15 minutes, following the steps in section 2, point 7. If your parent is drowsy, unconscious or cannot swallow, give nothing by mouth and call 1669 immediately.

Should an older adult with no energy rest or exercise?

Once a doctor has found nothing urgent, gentle daily movement is better than resting in bed all day. Start with short walks around the house regularly through the day, and have a physiotherapist assess before serious strength training, especially if your parent has fallen or has heart disease.

Can KIN HomeCare send a physiotherapist to help rebuild strength at home?

Yes, in Bangkok and surrounding provinces. Home physiotherapy costs 1,800 baht per session, with the first session at 1,500 baht until 31 December 2026. The physiotherapist assesses first and then designs a programme to suit your parent. Travel charges depend on the area and are confirmed by our staff before booking.

Talk to the KIN HomeCare team

If your parent is becoming more tired and you are not sure where to start, call and describe the symptoms, or send the symptom record and photos of the medicine packets on LINE. Our team will help you decide whether to see a doctor first, arrange a nurse home visit or start home physiotherapy.

• Home physiotherapy: call 095-767-6307 (+66 95 767 6307) (backup 061-881-9399)
• Nurse home visits, caregivers and hospital escort: call 061-881-9399 (+66 61 881 9399)
• LINE @KINHOMECARE
• Free consultation: our team helps you work out which service fits.

This information is general guidance for families and does not replace advice from the doctor caring for your parent.

Written by Orrathai Boontuang, RN (licence 5311192883) · Medically reviewed by Dr. Kamolchat Choktanomsup (licence 40854) · Prices as of October 2026; please confirm with our staff before booking.