High blood calcium (hypercalcaemia)

What is it?

Hypercalcaemia means there is too much calcium in your blood. This can make you feel ill.

What causes it?

Cancer in your bones can damage them and cause calcium to leak from your bones into your bloodstream.

Cancer can also affect your kidneys, so they can’t work as well to remove excess calcium from your blood. If you are very dehydrated after being sick a lot or having diarrhoea, this can increase blood calcium too.

The types of cancer usually associated with hypercalcemia are:

The types of cancer most commonly associated with hypercalcemia are:

What are the symptoms?

Feeling tired or weak
Losing your appetite
Constipation
Feeling irritable or low
Excessive thirst
Needing to pee a lot
Feeling sick or getting sick
Muscle spasms
Irregular heartbeat
Bone pain
Drowsiness, agitation or confusion
Personality changes

What should I do if I have symptoms?

Symptoms can sometimes be mild and can be caused by other things, but it’s important to tell your doctor if you have these symptoms. If high calcium is left untreated it can cause a coma or even death.

Your doctor can check your calcium level with a blood test and check how well your kidneys are working. If your calcium is too high your doctor can recommend treatments.

You don’t need to reduce the amount of calcium you eat - the high level of calcium in your blood is not caused by your diet.

How is high blood calcium treated?

You will need to spend some time in hospital to get your calcium levels down if your blood calcium is high. The type of treatment you have will depend on your calcium level and the symptoms you are experiencing. The team may decide to do other tests such as an ECG or a blood test to see how your kidneys are functioning. You may need to be connected to a drip as fluids help flush out excess calcium.

Drinking plenty of fluids will help too. With treatment, you should feel much better after a few days. If you are experiencing nausea and vomiting, the team will give you medication to help manage these symptoms.

You may also get bone strengthening drugs such as bisphosphonates, which can help to lower the amount of calcium in your blood and stop further damage to your bone. Read more about bone-strengthening drugs.

Steroids can help to reduce calcium levels, these may be given as tablets or by drip.