A hormone replacement to control calcium in hypoparathyroidism
Parathyroid hormone
A hormone replacement used to help control calcium levels in people with hypoparathyroidism.
What is Parathyroid hormone?
Parathyroid hormone is a specialist hormone replacement used in people with hypoparathyroidism, a condition where the body does not make enough of its own parathyroid hormone and so cannot keep blood calcium at the right level. It is given as an injection under the skin to help control calcium when standard treatment with calcium and vitamin D alone is not enough. The main focus of treatment is careful monitoring of blood calcium, as levels can swing too high or too low. There is also a precautionary warning, carried over from the related class of medicines, about a rare bone tumour (osteosarcoma) seen in animal studies, so it is used under specialist care.
Education and reference only. This is a plain-language guide to Parathyroid hormone — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Parathyroid hormone is a man-made version of a natural hormone that the parathyroid glands normally produce to keep blood calcium at the right level. It is used as a replacement in people with hypoparathyroidism, a condition in which these glands do not make enough hormone, so calcium tends to fall too low. It is given as an injection under the skin and is added on to, or used to reduce the need for, the usual calcium and vitamin D treatment in people whose calcium is difficult to control. It is a specialist treatment, started and supervised by a hormone (endocrine) specialist.
How it works
In healthy people, parathyroid hormone tells the body to release calcium from the bones, hold on to calcium in the kidneys and help activate vitamin D, all of which keep blood calcium steady. In hypoparathyroidism this signal is missing, so calcium drops. The medicine replaces that missing hormone, restoring the signals that keep calcium at a healthier level and reducing the large amounts of calcium and vitamin D tablets some people would otherwise need. Because the hormone has powerful effects on calcium, the dose has to be balanced carefully so that calcium does not rise too high or fall too low, which is why blood tests are central to treatment.
Company & origin
Originated / developed by: Specialist manufacturer.
A specialist hormone replacement used in the UK to help control calcium levels in people with hypoparathyroidism whose calcium is hard to manage with standard treatment.
Practical use
How to take Parathyroid hormone
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Inject it under the skin using the device exactly as your specialist team has trained you.
- Attend all blood tests so your calcium can be checked and the dose kept right.
- Do not change your calcium or vitamin D tablets yourself; these are adjusted alongside it by your team.
- Do not stop it suddenly, as your calcium can fall sharply; any changes should be guided by your specialist.
- Report symptoms of high or low calcium, such as tingling, cramps, feeling very thirsty, confusion or feeling unwell, promptly.
Weighing it up
Advantages & disadvantages of Parathyroid hormone
Advantages
- Replaces the missing hormone in hypoparathyroidism, helping to control calcium when standard treatment is not enough.
- Can reduce the large amounts of calcium and vitamin D tablets some people would otherwise need.
- Works in the body's own natural way of keeping calcium balanced.
Disadvantages
- Needs careful, regular blood-test monitoring, as calcium can go too high or too low.
- Has to be given by injection under the skin.
- Carries a precautionary warning about a rare bone tumour from animal studies, so it is used with caution.
Practical use
Good to know
The most important part of treatment with parathyroid hormone is careful, regular monitoring of blood (and sometimes urine) calcium, because the level can move too high or too low, especially when the dose is being adjusted, and both extremes can cause symptoms and harm. Doses of calcium and vitamin D are usually adjusted alongside it, so people should not change any of their tablets without specialist advice. A specific safety point is a precautionary warning about a rare bone cancer (osteosarcoma) that was seen in long-term animal studies with this group of medicines; because of this, it is used with caution and avoided in people at higher risk of bone cancer. It is given by injection under the skin, and people are trained in how to use the device. Because stopping it suddenly can cause calcium to fall sharply, it should never be stopped without medical guidance.
Who should not take it / use with caution
- People at higher risk of bone cancer (osteosarcoma), such as those who have had radiotherapy affecting the bones or certain bone conditions, should not normally use it.
- People who have had a serious allergic reaction to it should not use it.
- It is used with caution in pregnancy and breastfeeding, and only under specialist guidance.
- It is used with care in people with certain bone or calcium-related conditions.
Monitoring
- Regular blood tests for calcium (and sometimes urine calcium) to keep the level in the right range.
- Adjusting the dose and the accompanying calcium and vitamin D as needed.
- Watching for symptoms of high or low calcium and reviewing bone health over time.
Side effects
- Calcium going too high (causing thirst, tummy upset, tiredness or confusion) or too low (causing tingling, cramps or spasms).
- Nausea, headache or tingling, especially when treatment is being adjusted.
- Reactions where the injection is given.
- A precautionary concern about a rare bone tumour, which is why it is used with caution and monitored.
Key interactions
- Calcium and vitamin D supplements are balanced carefully with it, so they should only be changed on specialist advice.
- Medicines that affect calcium, such as some water tablets (diuretics), may need review.
- Certain heart medicines such as digoxin can be more affected if calcium swings, so the team will take this into account.
Available as: A solution given by injection under the skin using a pen device.
Answers
Parathyroid hormone: frequently asked questions
What is parathyroid hormone used for?
It is a hormone replacement used in hypoparathyroidism to help control blood calcium when standard treatment with calcium and vitamin D alone is not enough.
Why are blood tests so important?
Because the medicine has powerful effects on calcium, the level can move too high or too low, so regular blood tests are used to keep it in the right range and adjust the dose.
Is there a cancer warning?
There is a precautionary warning about a rare bone tumour (osteosarcoma) seen in long-term animal studies with this group of medicines, so it is used with caution and avoided in people at higher risk of bone cancer.
Can I stop it if I feel well?
No. Stopping it suddenly can cause your calcium to fall sharply, so it should only be changed or stopped under specialist guidance.
How is it given?
It is given as an injection under the skin using a pen device, and your team will train you in how to use it.
Authoritative sources
- BNF
- NICE CKS
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