A low-molecular-weight heparin injection
Tinzaparin
A low-molecular-weight heparin injected under the skin to prevent and treat blood clots.
What is Tinzaparin?
Tinzaparin is a low-molecular-weight heparin given as an injection under the skin to prevent and treat blood clots in the veins and lungs. It thins the blood so existing clots do not grow and new ones are less likely to form. It can cause bruising at the injection site and, rarely, a serious drop in platelets, and the team must be told before any spinal or epidural procedure.
Education and reference only. This is a plain-language guide to Tinzaparin — 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
Tinzaparin is a low-molecular-weight heparin (LMWH), a type of injectable blood-thinning medicine. It is used to prevent and treat blood clots in the deep veins (deep vein thrombosis) and lungs (pulmonary embolism), and to prevent clots in people at higher risk, such as after surgery or during a hospital stay. It is given as an injection under the skin and is often used during pregnancy when a blood thinner is needed.
How it works
Tinzaparin boosts the action of a natural blood protein that switches off key clotting factors, particularly one called factor Xa. By damping down the clotting process, it stops existing clots from growing and makes new clots less likely while the body breaks the clot down. It does not dissolve a clot directly but gives the body time to do so safely.
Company & origin
Originated / developed by: Originally developed by Leo Pharma..
A low-molecular-weight heparin made from standard heparin, introduced in the 1990s for preventing and treating blood clots.
What it treats
Conditions Tinzaparin is used for
Practical use
How to take Tinzaparin
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- It is injected just under the skin, usually into the tummy, by you, a carer or a nurse.
- Rotate the injection site each time to reduce bruising and soreness.
- Do not rub the area after injecting, as this can increase bruising.
- Use it at around the same time each day if you are on a regular preventive schedule.
- Tell your team before any planned spinal or epidural procedure, dental work or surgery.
- Report unusual bruising or bleeding, blood in the urine or stools, or a bad headache straight away.
Weighing it up
Advantages & disadvantages of Tinzaparin
Advantages
- Reliable, predictable blood-thinning that usually does not need routine clotting blood tests.
- Can be given at home by injection, allowing treatment to continue outside hospital.
- Often suitable in pregnancy, when many tablet blood thinners are not.
Disadvantages
- Has to be given by injection rather than as a tablet, which some people dislike.
- Increases the risk of bruising and bleeding, including at the injection site.
- Needs extra care, and sometimes dose changes or a different choice, in people with kidney problems.
Practical use
Good to know
Tinzaparin is given as an injection just under the skin, often into the tummy, and many people or their carers are taught to do this at home. Rotate where you inject to reduce bruising, and some bruising at the site is normal. Tell any doctor, nurse or dentist that you are using it before procedures, and it is very important to tell your team before any planned spinal or epidural injection because of the risk of bleeding around the spine.
Who should not take it / use with caution
- People with active major bleeding or a very high bleeding risk.
- People who have had heparin-induced thrombocytopenia (a serious heparin reaction affecting platelets).
- People who have had a serious allergic reaction to heparin; care is also needed with significant kidney disease.
Monitoring
- Platelet count, particularly in the early weeks, to watch for a heparin reaction.
- Kidney function, as this affects how the medicine is handled, especially in older people.
- Potassium in people at risk, and signs of bleeding throughout treatment.
Side effects
- Bruising, soreness or a lump where the injection is given.
- Bleeding more easily, such as nosebleeds or bleeding gums.
- A fall in platelets, occasionally as part of a serious reaction (HIT).
- Raised potassium in the blood, particularly in people at risk.
- Rarely, changes in liver blood tests or an allergic reaction.
Key interactions
- Other blood thinners and antiplatelet medicines, such as aspirin and clopidogrel, which add to bleeding risk.
- Anti-inflammatory painkillers (NSAIDs), which can increase the risk of bleeding.
- Medicines that raise potassium, which together with tinzaparin can push potassium higher.
Available as: Pre-filled syringe (and vials) for injection under the skin.
Answers
Tinzaparin: frequently asked questions
Where do I inject tinzaparin?
It is injected just under the skin, usually into the tummy, rotating the site each time. Many people or their carers are taught to do this at home, and a nurse can show you how.
Is bruising at the injection site normal?
Some bruising and soreness where you inject is common and usually harmless. Rotating sites and not rubbing the area afterwards helps. Report unusually large or spreading bruises to your team.
Why must I tell my team before a spinal or epidural?
Blood thinners like tinzaparin raise the risk of bleeding around the spine during or after a spinal or epidural injection, which can be serious. Your team needs to plan the timing carefully.
Can I take tinzaparin in pregnancy?
Low-molecular-weight heparins are often the preferred blood thinner in pregnancy, as many tablet blood thinners are not suitable. Your team will advise on whether and how to use it.
What is heparin-induced thrombocytopenia?
It is an uncommon but serious reaction where heparin causes platelets to fall and, paradoxically, new clots to form. Your platelet count may be monitored, and the medicine is stopped if it is suspected.
The wider class
About Heparins
Tinzaparin belongs to the heparins class. For how the class as a whole works, its shared safety principles and monitoring, see the full guide.
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Authoritative sources
- BNF
- NICE CKS
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