Heparin belongs to the class of active substances known as anticoagulants – these are substances that inhibit blood clotting. Because of this effect, the active ingredient is used for the prevention and treatment of thrombosis, as well as for the treatment of bruising. Depending on the treatment objective, it is either applied in the form of ointments and gels or injected as a solution. Like any other active ingredient, heparin has side effects; however, the substance is generally considered to be well tolerated.
Effect of heparin
Heparin ensures that blood clotting is inhibited in our body. This occurs primarily by the active substance binding to the enzyme antithrombin III. Together, the two substances then switch off activated clotting factors in the blood. However, it also binds calcium ions – the lower their concentration in the blood, the more difficult it is for the blood to clot. Because of its anticoagulant effect, heparin is used primarily to prevent embolisms and thromboses. It is also frequently used to treat existing thromboses. In addition, however, the active ingredient is also used in other situations:
- For the therapy of a heart attack or angina pectoris.
- Together with zinc to fight herpes viruses.
- In doctors’ offices and hospitals to prevent clotting of blood samples.
Externally, heparin is used to treat superficial phlebitis and to reduce swelling in bruises and contusions. In swelling, the active ingredient promotes blood flow and thus the return of blood to the heart. This reduces the accumulation of water in the neighboring vessels and the swelling subsides. In addition, heparin can also cause blood clots in the vessels immediately beneath the skin to dissolve.
Heparin in ointments and creams
Heparin comes in a variety of dosage forms: The active ingredient is found in ointments and gels, but there are also heparin solutions that must be injected by syringe. In ointments and creams, the active ingredient is usually used to treat bruises and contusions. Unless otherwise prescribed, the ointments should be used externally two to three times a day. When applying the ointment, care should be taken to ensure that it does not get onto open wounds, inflamed areas of skin or mucous membranes. Heparin injections, on the other hand, are used after operations, for example, to reduce the risk of thrombosis. People whose mobility is restricted for a longer period after an operation often have to continue injecting themselves with heparin after the end of their hospital stay. The active ingredient can be injected either into a venous blood vessel or into the subcutaneous fat tissue – ask your treating physician about the options for your medication.
Consider contraindications
While heparin in ointments and creams can be used externally without hesitation, with a few exceptions that you can find in the package insert of your medication, there are some contraindications for the use of injection solutions. For example, the active ingredient must not be injected if there is type II thrombocytopenia – a blood platelet deficiency – or severe high blood pressure. In addition, it must not be used in some other cases:
- In cases of suspected cerebral hemorrhage
- Immediately after an abortion.
- Together with anesthetic injections into the spinal cord and punctures of the spinal cord.
- For ureteral and kidney stones
- For alcohol abuse
In general, heparin should be used only with extreme caution and after consultation with a doctor in all diseases associated with an increased tendency to bleed. Patients who have a damaged kidney or liver must be regularly monitored by the attending physician during treatment.
Drug Interactions
If other anticoagulants – for example, other anticoagulants or agents such as acetylsalicylic acid – are used during treatment with heparin, this may increase the tendency to bleed. If the active ingredient is taken together with propranolol, the effect of the beta-blocker may be enhanced. When taken together with certain other medications, the effect of heparin may also be weakened.These agents include certain allergy medications (H1 antihistamines), antibiotics (tetracyclines), and heart-strengthening agents (cardiac glycosides). Nicotine and vitamin C may also have such an effect. For a detailed list of interactions with other agents, please refer to your medication’s package insert.
Heparin during pregnancy and lactation
Heparin can be used during both pregnancy and lactation because it is not placental and does not pass into breast milk. However, if the agent is used internally for several months during pregnancy, this may lead to an increase in the risk of osteoporosis. In addition, it cannot be ruled out that internal use may increase the likelihood of miscarriage or stillbirth. During breastfeeding, however, heparin can be used without concern. If heparin is applied externally, the above-mentioned risks do not exist. However, if the dosage of the active substance is very high, the tendency to bleed may subsequently increase. In such cases, peridural anesthesia during labor is not possible.