A way of replacing selenium when the body is short of it
Selenium injection
A way of giving selenium, a trace element the body needs in small amounts, when someone is deficient or being fed entirely by drip.
What is Selenium injection?
Selenium injection is used to replace selenium, a trace element the body needs in tiny amounts to work properly. It is mainly used in people who are fed entirely by a drip (intravenous or parenteral nutrition) over a long period, who can become short of selenium, and in others with proven deficiency. It is generally well tolerated when given as directed. The main thing to be aware of is that too much selenium is toxic and can cause hair and nail changes, stomach upset and other problems, so it is given under supervision with levels checked.
Education and reference only. This is a plain-language guide to Selenium injection — 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
Selenium injection is a specialist preparation used to top up selenium, a trace element that the body needs in very small amounts for the normal working of certain enzymes and the immune system. It is given by injection or added to a feeding drip, mainly for people who are fed entirely through a vein for a long time and so do not get selenium from food, or for others who have a proven deficiency. It is part of the careful balance of vitamins and minerals that has to be supplied when someone cannot eat normally, and is used under medical and dietetic supervision.
How it works
Selenium is needed for certain enzymes that protect cells from damage and for the normal working of the thyroid and immune system. When someone cannot take in selenium from food, for example because they are fed entirely by drip, their stores can run low and these processes can be affected. The injection simply restores the body's selenium to a healthy level so those enzymes can work normally again. Because the body needs only a tiny amount, the goal is to replace what is missing without giving too much, which is why the dose is matched to the person's needs and levels are checked.
Company & origin
Originated / developed by: Specialist manufacturers.
A specialist preparation used in the UK to replace selenium, a trace element, mainly in people fed by drip (intravenous or parenteral nutrition).
Practical use
How to take Selenium injection
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- It is given by injection or added to a feeding drip by the team, not something you take yourself.
- It is mainly used when you are fed entirely by a drip or have a proven selenium deficiency.
- The amount is matched to your needs so that a shortage is corrected without giving too much.
- Tell the team about any other supplements you take, as extra selenium adds up.
- Report symptoms such as hair or nail changes, stomach upset or a garlic-like breath smell, which can suggest too much.
Weighing it up
Advantages & disadvantages of Selenium injection
Advantages
- Corrects a selenium shortage, especially in people fed entirely by a drip.
- Restores the normal working of selenium-dependent enzymes and the immune system.
- Generally well tolerated when given as part of carefully balanced nutrition.
Disadvantages
- Too much selenium is toxic, so it must be given under supervision.
- Mainly relevant to specialist settings such as long-term drip feeding.
- Levels may need checking to keep replacement in the right range.
Practical use
Good to know
The key point with selenium is that it is needed in only very small amounts, so the aim is to replace a shortage rather than to give large amounts: too much selenium is toxic. Signs of having too much include hair loss, brittle or changed nails, stomach upset, a garlic-like smell on the breath, tiredness and irritability, so it is given under supervision with selenium levels checked when needed. It is mainly relevant to people fed entirely by a drip over a long time, where it is one of several trace elements that have to be supplied. As with anything added to a feeding drip, it is prepared and given carefully by the team looking after intravenous nutrition. Most people tolerate appropriate replacement well.
Who should not take it / use with caution
- People who already have enough selenium do not need it, as extra can build up and cause harm.
- It is used with care in people with kidney problems, who may clear it less easily, under specialist guidance.
- People who have had a serious allergic reaction to the preparation should not be given it.
Monitoring
- Checking selenium levels where needed to guide replacement.
- Watching for signs of too much, such as hair, nail or stomach changes.
- Reviewing the overall balance of trace elements in people fed by a drip.
Side effects
- Usually well tolerated when the right amount is given.
- With too much, hair loss, brittle nails, stomach upset and a garlic-like smell on the breath.
- With too much over time, tiredness, irritability and other problems linked to selenium excess.
Key interactions
- Other selenium-containing supplements add to the total, so tell the team about them.
- It is balanced against other trace elements and vitamins given in a feeding drip.
- There are few well-known medicine interactions, but always share your full medicines and supplements list.
Available as: A solution for injection or for adding to a feeding drip.
Answers
Selenium injection: frequently asked questions
What is selenium injection used for?
It is used to replace selenium, a trace element the body needs in small amounts, mainly in people fed entirely by a drip or with a proven deficiency.
Why does the dose need to be careful?
The body needs only a tiny amount of selenium and too much is toxic, so the aim is to correct a shortage without giving more than is needed.
What happens with too much selenium?
Signs of excess include hair loss, brittle nails, stomach upset, a garlic-like breath smell and tiredness, which is why levels are monitored.
Who is most likely to need it?
People fed entirely through a vein over a long period are most likely to become short of selenium and to need replacement as part of their nutrition.
Is it something I take at home?
No. It is given by injection or added to a feeding drip by the team looking after your nutrition, not taken by yourself.
Authoritative sources
- BNF
- NICE CKS
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