Home Medicines Ticagrelor: effect, areas of application, side effects

Ticagrelor: effect, areas of application, side effects

by Josephine Andrews
Published: Last Updated on 319 views

Ticagrelor is what is known as a platelet aggregation inhibitor. It therefore prevents the platelets from aggregating and forming blood clots in the vessels. The active ingredient is usually combined with acetylsalicylic acid, which also inhibits blood clotting – but in a different way. This combination of active ingredients is called “dual platelet inhibition”. Here you can read more about the effects and use of ticagrelor, dosage and side effects.

How ticagrelor works

The anticoagulant ticagrelor specifically inhibits a specific binding site on the surface of the blood platelets (thrombocytes), the so-called P2Y12 receptor for ADP. This suppresses the activation of further blood platelets and also the further “self-activation” of the platelets. The combination of ticagrelor with acetylsalicylic acid (ASA) in dual platelet inhibition also prevents the formation of thromboxanes, which further reduces the ability of blood platelets to clot.

When blood leaks from the body’s vascular system, the body tries to stop the blood loss. For this purpose, blood coagulation is activated. It forms a clot at the exact spot to seal the leak. The platelets, which make up the third type of blood cell in addition to the red and white blood cells, have an important function.

The task of the blood platelets is to detect a leak in the blood vessel and subsequently initiate clotting. To do this, the blood platelets attach to the injured area with the help of other proteins in the blood and are activated, doing everything possible to close the vessel as quickly as possible.

They also release messenger substances (such as thromboxane and ADP) that attract and activate more platelets. The released blood platelets also have docking points (receptors) for these messenger substances – they activate themselves even more. This is referred to as a “positive feedback loop”.

If this process is disturbed by various factors so that it can be activated in an overly sensitive manner, a coagulation disorder is present. Larger clots can then also form in intact blood vessels. These can then block important vessels that supply the brain or heart , for example – with consequences such as a stroke or heart attack.

To avoid this, medication is used to intervene in the coagulation process, for example with ticagrelor.

intake, degradation and excretion

After ingestion, about a third of ticagrelor is absorbed from the intestine into the bloodstream, where it reaches its maximum blood level after one and a half hours. The anticoagulant is partially converted in the liver by the cytochrome P450 enzyme system into a different but equally effective compound.

Both ticagrelor itself and its metabolite are eliminated from the body to a small extent in the urine but mainly in the faeces. After seven to eight hours, the level of ticagrelor in the blood has fallen to about half of the dose taken.

When is ticagrelor used?

Ticagrelor in combination with acetylsalicylic acid (ASA) is indicated for the prevention of clot formation in adult patients with:

  • acute coronary syndrome (collective term for unstable angina pectoris, heart attack and sudden cardiac death )
  • a history of blockage (heart attack) or severe narrowing (angina pectoris) of the coronary arteries and an increased risk of developing an atherothrombotic event (cardiovascular death, heart attack or stroke)

In the lower dose of 60 milligrams, ticagrelor is prescribed in combination with ASA to prevent atherothrombotic events in patients with a known heart attack that was at least 12 months previously.

Ticagrelor must be taken long-term to provide sustained suppression of clot formation. The duration of treatment is determined individually and is usually one year.

How ticagrelor is used

At the beginning of treatment with ticagrelor, 180 milligrams of the active ingredient are taken, then 90 milligrams twice a day at intervals of about twelve hours. It can be taken with or without a meal.

If the patient has difficulty swallowing or is being fed through a feeding tube, the ticagrelor tablet can be crushed and given suspended in water. Alternatively, there are ticagrelor orodispersible tablets that dissolve in the mouth.

For follow-up treatment in high-risk patients after a heart attack, 60 milligrams of ticagrelor are taken twice a day at intervals of about twelve hours.

If you miss a dose, you should not take it afterwards. Instead, you simply take the next dose at the usual time. Two doses must not be taken at the same time!

What are the side effects of ticagrelor?

Ticagrelor causes nosebleeds, shortness of breath, bleeding in the gastrointestinal tract, bruising, bleeding of the skin and subcutaneous tissue in one to ten percent of patients.

Dizziness, headache, bleeding in the skull , bleeding in the eyes, coughing up blood, vomiting blood, gastrointestinal ulcers, bleeding in the oral cavity, skin rash, itching, bleeding in the urinary tract and vaginal mucosa, and a weakening of the immune system are also occasionally seen .

What should be considered when taking ticagrelor?

Contraindications

Ticagrelor must not be taken if:

  • Hypersensitivity to the active substance or any of the other components of the drug
  • active bleeding
  • History of bleeding within the skull (intracranial haemorrhage).
  • severe hepatic impairment
  • concomitant use of strong CYP3A4 inhibitors (such as clarithromycin, itraconazole, ritonavir)

interactions

There are many possible interactions of ticagrelor with other drugs. Before starting treatment, it should therefore be checked which other medications the patient is taking.

Ticagrelor is broken down in the liver by the enzyme cytochrome P450 3A4, which also breaks down many other active substances in the body. Some of these active substances can block the enzyme, causing blood levels of ticagrelor to rise.

These active ingredients include, for example, certain antibiotics (such as clarithromycin, metronidazole , chloramphenicol), antifungal medicines (such as fluconazole, ketoconazole, itraconazole), some HIV medicines (such as ritonavir, indinavir, nelfinavir), and many herbal remedies (such as ginseng , valerian , grapefruit juice).

Conversely, some substances can increase the amount of the enzyme cytochrome P450 3A4, which increases the breakdown of ticagrelor. Examples include anti -epileptic and anti-seizure drugs (like phenytoin, carbamazepine, phenobarbital), some foods (like ginger , garlic , licorice), and the herbal antidepressant St. John’s wort.

Ticagrelor can also affect the breakdown of other medicines by blocking certain proteins. The anticoagulant may increase the concentration of drugs such as digoxin (heart medication), ciclosporin (in autoimmune diseases and after organ transplants), atorvastatin (cholesterol reducer) and verapamil (e.g. against cardiac arrhythmias).

Close monitoring is recommended at the start of ticagrelor treatment, especially in the case of drugs with a narrow therapeutic index. Such drugs are only therapeutically effective in a narrow dose range; if the dose is increased, overdose with corresponding side effects can quickly occur.

age restriction

The safety and efficacy of ticagrelor in children and adolescents below 18 years of age have not been established.

pregnancy and breast feeding period

There are limited data from the use of ticagrelor in pregnant women. Animal studies revealed a fertility-endangering and teratogenic effect (reproductive toxicity). Therefore, the active ingredient is not recommended for pregnant women.

In animal studies, ticagrelor and its active metabolite are excreted in human milk. It is not known whether this is also the case in humans. A risk to the infant if the nursing mother takes ticagrelor cannot therefore be ruled out. Based on a benefit-risk assessment, a decision should be made on a case-by-case basis as to whether breastfeeding should be discontinued as a precaution or ticagrelor should be discontinued.

How to get medication with ticagrelor

Preparations with the active ingredient ticagrelor require a prescription in Germany, Austria and Switzerland and are therefore only available in pharmacies with a doctor’s prescription.

Since when is ticagrelor known?

Ticagrelor was developed as the first drug that reversibly inhibits platelet activation by ADP. It was introduced to the European market in 2011.

The novelty and the considerable additional benefit of the active ingredient were also recognized in Germany by the Federal Joint Committee, which sets the fixed prices for pharmaceuticals in this country. For this reason, preparations with the active ingredient ticagrelor are comparatively expensive, but have the advantage that they can reduce mortality after a heart attack more than previous therapies.

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