Pallor (pale skin): causes, red flags and when to get checked

Pale skin results from reduced blood flow near the surface or fewer red blood cells, or less haemoglobin, to colour the blood. It is best judged where the skin is thin and well supplied with blood: the inner lower eyelid, the lips and gums, the palms and the nail beds. Everyone varies in natural skin tone, so what matters is a change from your usual.

The NHS notes, in discussing anaemia-related symptoms, that on brown or black skin a paler appearance may be easier to see on the palms of the hands, the soles of the feet or the inside of the eyelids. Comparing your palm with someone else's, or looking in natural daylight, helps. Because pallor may develop gradually, family and friends often notice it before you do.

The NHS says symptoms of iron deficiency anaemia can include tiredness and lack of energy, shortness of breath, noticeable heartbeats, paler than usual skin and headaches. Less common symptoms include ringing in the ears, food tasting strange, itching, a sore tongue, hair loss, wanting to eat non-food items such as ice or paper (pica), difficulty swallowing, mouth ulcers at the corners of the mouth, spoon-shaped nails and restless legs.

On causes, the NHS says heavy periods and pregnancy are very common causes, and that bleeding in the stomach and intestines is another common one, caused by anti-inflammatory drugs such as ibuprofen and aspirin, stomach ulcers, inflammation of the bowel or food pipe, piles, and less commonly cancers of the bowel or stomach. Finding the reason matters as much as replacing the iron.

Pernicious anaemia, an autoimmune condition preventing the absorption of vitamin B12, is described by the NHS as the most common cause of B12 deficiency in the UK, and some medicines, including anticonvulsants and proton pump inhibitors, can reduce how much of these vitamins the body absorbs.

• Call 999 or go to A&E if pallor comes with collapse, fainting, cold clammy skin, a very fast pulse or severe breathlessness, which may mean significant blood loss or shock.

• Call 999 or go to A&E if you are vomiting bright red blood or ground-coffee vomit, or passing black, sticky, very smelly stool or large amounts of fresh blood, as the NHS stomach ulcer and bowel cancer pages advise.

• Call 999 for pallor with chest pain, or confusion and drowsiness.

• Ask for an urgent GP appointment or contact NHS 111 if pallor comes with unusual bruising or bleeding, repeated infections, fever, bone pain or swollen glands; the NHS advises urgent assessment for acute myeloid leukaemia symptoms, and the GP will usually arrange an urgent blood test.

• See a GP if you are persistently pale, tired and short of breath, have very heavy periods, or have noticed bleeding from the bowel; the NHS says to see a GP if you think you might have iron deficiency anaemia.

• In a child or baby, new marked paleness with floppiness, poor feeding or drowsiness should be assessed urgently.

The GP will ask about tiredness, breathlessness, palpitations, heavy periods, pregnancy, black stool or bleeding, diet (including vegan or restrictive diets), medicines such as NSAIDs and PPIs, weight loss and family history of blood disorders. They look at the eyelids, palms, tongue and nails, check pulse and blood pressure and feel for enlarged glands, liver or spleen.

The NHS says the GP will usually do a full blood count to find out whether the number of red blood cells is normal, with no preparation needed, and that if the reason for anaemia is unclear a faecal immunochemical test for blood in the stool may be done and a referral for specialist checks may follow. Ferritin, B12 and folate levels are commonly added.

For iron deficiency anaemia the NHS says iron tablets will be recommended, usually for about 6 months, with repeat blood tests to check the level returns to normal. Side effects include constipation or diarrhoea, tummy pain, heartburn, feeling sick and darker than usual poo, and taking tablets with or soon after food may reduce them. Iron tablets must be kept out of reach of children, as an overdose in a young child can be fatal. Iron-rich foods include dark green leafy vegetables, fortified cereals, meat, dried fruit and pulses, while tea, coffee, milk and high-phytate foods reduce absorption.

For B12 or folate deficiency, the NHS says most cases are treated with injections or tablets, with B12 usually given by injection at first, and folic acid tablets usually taken for 4 months. Heavy periods can be treated with medicine, and stomach ulcers with the treatments described on the NHS stomach ulcer page.