Swollen Legs in Older Adults: Causes, Home Care and Warning Signs

What swelling is

Swelling in the legs, called oedema, is fluid that has leaked from the small blood vessels into the tissues. It usually collects in the lowest parts of the body: the feet and ankles when standing or sitting, and the lower back and buttocks in a person lying in bed. A sign of oedema is pitting: if you press a thumb on the shin or ankle for a few seconds and release, a dent remains. Swelling may be mild or severe, in one leg or both, painless or tender, with normal or changed skin.

Common causes

Prolonged sitting or standing, heat and humidity. Gravity and weak calf muscle pumping let fluid pool. Common in hot weather, on long journeys and in people who sit all day. Both ankles are usually swollen, with no pain, and it improves with elevation and overnight.

Chronic venous insufficiency and varicose veins. Vein valves weaken, blood pools and fluid leaks. Swelling is often worse in the evening, with heaviness, aching, itching, darkened skin and sometimes ulcers. See compression stockings guide.

Heart failure. The heart pumps less effectively, and fluid backs up. Both legs swell, with breathlessness (especially lying flat or on exertion), tiredness, weight gain and night-time cough or urination. See heart failure at home guide and daily weights in heart failure.

Kidney disease. Damaged kidneys retain salt and water. Swelling may appear around the eyes in the morning and in the legs later. See chronic kidney disease home care.

Liver disease. Low albumin and portal hypertension cause leg and abdominal swelling.

Low protein or malnutrition. Poor diet reduces blood protein, which lets fluid leak; see malnutrition in older adults.

Medicines. Some blood pressure medicines, steroids, anti-inflammatory painkillers, some diabetes and hormonal medicines can cause fluid retention. Do not stop any medicine on your own; ask the doctor or pharmacist; see medicine side effects families should watch and painkillers and older adults.

Thyroid disease. Underactive thyroid can cause puffy swelling; see thyroid problems in older adults.

Deep vein thrombosis (DVT). A blood clot in a deep vein, usually one leg, with pain, warmth, redness and swelling of the calf or thigh. It can break off to the lungs. This is an emergency. People at higher risk include those who are bedbound, have recently had surgery, a fracture or illness, have cancer or have travelled long distances.

Infection (cellulitis). A red, hot, tender, swollen area of skin, often with fever. Needs urgent treatment.

Lymphoedema. Blockage of lymph drainage, often after cancer treatment or infections, causing long-term swelling.

Injury and arthritis. A sprain, fracture, or inflamed joint such as gout may swell the foot or ankle; see gout in older adults.

Paralysed or immobile limbs. After stroke, a weak limb often swells.

Pelvic or abdominal pressure, such as tumours or severe constipation.

Pregnancy-related or hormonal causes are less relevant in older age, but some hormone treatments cause swelling.

Clues that help tell causes apart

• One leg or both? One-sided swelling suggests a local cause, such as a clot, injury, infection or a vein problem. Both legs suggest a general cause such as heart, kidney, liver, medicines or venous disease. A sudden one-sided swelling with pain needs urgent assessment.
• Pain and redness? Painful, red, warm swelling suggests clot or infection. Painless swelling suggests oedema.
• Breathlessness, tiredness, weight gain? Think heart or kidney.
• Timing. Worse in the evening and better in the morning suggests gravity and veins; persistent swelling that does not improve overnight suggests a systemic cause.
• Skin changes. Brown staining, itching and eczema near the ankles suggest venous disease; shiny, tight skin suggests severe oedema.
• Recent events. Surgery, hospital stay, long travel, a new medicine, illness, or reduced mobility.
• Other symptoms. Fever, chest pain, cough, jaundice, reduced urine, abdominal swelling.

A doctor will examine, check blood pressure and heart, and may arrange blood and urine tests, a heart tracing or echocardiogram, an ultrasound of the legs and other investigations.

Warning signs: seek help urgently

Call emergency services or go to hospital at once for:

• Sudden breathlessness, chest pain, coughing blood, fast heartbeat or fainting, with or without leg swelling: possible clot in the lung or heart failure. See when breathlessness is an emergency.
• A swollen, painful, warm, red calf or thigh, especially on one side, or after surgery, a long trip or immobility.
• A red, hot, rapidly spreading area with fever or chills.
• A cold, pale, blue or painful leg or foot.
• Swelling with confusion, severe weakness or passing very little urine.

Contact a doctor within a day or two for swelling that is new, worsening, one-sided without pain, accompanied by weight gain of a couple of kilograms in a few days, or that does not go down overnight.

Safe home care for mild, benign swelling

Once a doctor has said the swelling is not from a serious cause, or while waiting for an appointment for mild, painless, both-leg swelling:

Elevate the legs. Rest with the legs raised above the level of the heart for 20 to 30 minutes, several times a day, with pillows under the calves, not just a footstool; see leg elevation pillow guide. Do not use a pillow that bends the knees sharply or presses behind them. In bed, a wedge or pillows under the legs can help.

Move. Walk regularly, and do ankle pumps and heel raises while sitting. Avoid sitting or standing still for long; change position every half hour; see sitting for long hours and chair exercises for seniors.

Footwear. Wear comfortable, supportive shoes with room for swelling, and avoid tight socks or garters; see choosing shoes for older feet.

Salt and fluids. Reducing salt may help if advised; processed snacks, pickles and papads are high in salt. Do not restrict fluids without medical advice; see hydration for older adults.

Weight. Healthy weight reduces pressure on veins.

Heat. Avoid very hot baths and long exposure to heat, which dilate veins. Cool, not cold, water over the legs can feel good.

Avoid crossing the legs for long periods.

Compression: only after a doctor has checked arterial circulation and cause; see compression stockings guide and measuring, sizing and putting them on. Never use tight bandages or garters yourself.

Do not massage a swollen calf if there is any chance of a clot.

Do not stop water tablets or other medicines without medical advice.

Skin care

Swollen skin is fragile and slow to heal.

• Wash gently with mild soap, pat dry, and moisturise daily with a plain, fragrance-free moisturiser, as the doctor or nurse advises.
• Check the skin each day for cracks, blisters, redness, weeping, sores or signs of infection.
• Protect from bumps and scratches; cut nails short.
• Treat athlete's foot between the toes, which can let infection in.
• Do not apply heating pads or hot water bottles, which can burn skin that has reduced sensation.
• See a doctor or nurse for any wound, ulcer or weeping.
• See barrier cream and skin care, skin conditions in older adults and wound care at home for older adults.

Tracking swelling and weight

A simple record helps the doctor.

• Weigh each morning after passing urine, before breakfast, in similar clothing, on the same scale; see weighing scale and weight loss in seniors. A rise of 2 kg or more over a few days, in someone with heart failure, should be reported.
• Note the swelling: which leg, how high, pitting depth, skin colour, shoe tightness.
• Measure ankle and calf circumference with a tape at the same place each morning and evening.
• Record symptoms: breathlessness, number of pillows used at night, cough, urine.
• Record medicines and any changes.
• Take photographs of the legs in the same position and light.

Swelling in people who are bedbound or have a weak limb

In bed, fluid collects in the buttocks, back and heels, not only the feet. Check these areas. Elevate the legs and reposition regularly; see positioning a bedridden parent and preventing bedsores at home. A weak arm or leg after stroke needs support, elevation and gentle exercise as taught by a therapist.

When to ask a professional

See a doctor for any unexplained leg swelling, and urgently for the warning signs above. A nurse can advise on skin care, compression and monitoring. A physiotherapist can teach exercises and positioning. A dietician can advise on salt and nutrition. A pharmacist can review medicines. A vascular or heart specialist may be required for tests and treatment.