Clexane

Synonyms

Active ingredient: enoxaparin, enoxaparin sodium, synonyms in the broader sense: low molecular weight heparin, Lovenox® English: enoxaparin sodium, low molecular weight heparins (LMWH)

Definition

Clexane® belongs to the group of medicinal anticoagulants. These anticoagulants are divided into: Clexane® belongs to the group of low-molecular-weight heparins, which comprises various substances that differ from unfractionated heparin – only one substance – in their size and, in conjunction with this, in their mode of action. – unfractionated heparin

  • Low-molecular-weight heparins

Active substance name/trade name

The active ingredient of Clexane® is enoxaparin, a drug belonging to the group of low molecular weight heparins.

Chemical structure

First, heparin benzyl esters are obtained from pig intestines, which are then chemically modified. Finally, Clexane® is composed of polysaccharide chains (polysaccharides = multiple sugars), which in turn contain various uronic acids and glucosamines. Compared to unfractionated heparin Clexane® has a shorter chain length and a lower molecular weight (about 4500 Dalton). Clexane® is usually present in the form of the sodium salt (enoxaparin sodium).

Fields of application

Clexane® is used on the one hand as thrombosis prophylaxis, i.e. to prevent thrombosis (formation of blood clots in vessels) during and after operations or when carrying out renal replacement procedures (haemodialysis). Clexane® is also used in the treatment of leg vein thrombosis and certain heart diseases. These include unstable angina pectoris (a form of tightness in the chest caused by inadequate blood supply to the heart) and myocardial infarction (heart attack).

With regard to the treatment of myocardial infarction, the distinction between elevation and non-elasticity is important. A lifting infarction (STEMI = ST-elevation myocardial infarction) is characterized by certain changes in the ECG (electrocardiogram) – so-called ST segment elevations. In contrast, such changes do not exist in the case of a non ST-elevation myocardial infarction (NSTEMI).

Effect

Clexane® acts through the blood clotting cascade that is set in motion by the body to stop a source of bleeding. The exact points of action of Clexane® are two coagulation factors, Factor Xa (ten a) and Factor IIa (two a). These factors form part of the blood coagulation cascade and by inhibiting them, the rest of the cascade is also stopped, as subsequent coagulation factors are no longer activated. As a result, the clotting of the blood stops. Overall, Clexane® inhibits Factor Xa about three to five times more than Factor IIa.

Side effects

Like all drugs, the drug Clexane® with the active ingredient enoxaparin can lead to side effects and complications. Appropriate use and consideration of contraindications should minimize the risk of side effects. Very common side effects of Clexane® are bleeding.

These include bruises (haematomas), wound haematomas, bloody urine, increased nosebleeds, gastrointestinal bleeding and extensive skin bleeding, so-called ecchymoses. The risk of bleeding is increased if there are risk factors such as coagulation disorders, the intake of anticoagulant medication or the presence of surgical wounds. In addition, an increase in liver enzymes (transaminases) and platelet count is frequently seen.

The latter can lead to the formation of blood clots. Paradoxically, Clexane® can cause not only an increase in platelets but also their reduction. Other common side effects include allergic reactions, skin itching and redness.

A skin rash such as that which occurs after contact with nettles (urticaria) is also common. The injection site can be painful, hardened, swollen and reddened. There may also be extensive bleeding at the injection site.

Finally, headaches are also a common side effect of treatment with Clexane®. More rarely, severe bleeding, an increase in blood potassium levels, severe allergic reactions, anaemia, osteoporosis, liver damage and hair loss may occur. However, it must be stressed that the latter side effects in particular have been reported so rarely that their frequency cannot be stated.

Another very rare side effect, which can only occur when Clexane is used in connection with lumbar punctures and injections close to the spinal cord, is bruising, which can lead to nerve damage in the area of the spinal cord. This can result in paralysis. Therapy with Clexane® can also lead to so-called heparin-induced thrombocytopenia, or HIT for short.

However, the risk of HIT is lower with the use of Clexane® than with therapy with unfractionated heparin. There are two types of HIT, HIT I and HIT II. A HIT I is harmless and starts within the first 5 days after the start of therapy with Clexane®.

There is only a mild drop in platelets, which has no consequences and returns to normal quickly. A HIT II, on the other hand, is a dangerous complication that can occur between the 5th and 14th day of treatment. There is a massive drop in platelets, which is caused by a clumping of platelets.

The consequence is the formation of many blood clots that can clog vessels. A HIT II can be life-threatening, so in this case the therapy must be changed immediately. In order not to overlook a HIT II, regular laboratory checks are carried out during therapy with Clexane®. Click here for the main article Side effects of Clexane®