Ticagrelor โ€” NZ Medication Guide

What is Ticagrelor?

Ticagrelor is a P2Y12 adenosine diphosphate receptor antagonist antiplatelet medicine used to prevent cardiovascular events after acute coronary syndrome. This medication is funded by Pharmac under Special Authority for ACS and post-MI secondary prevention.

What is Ticagrelor Used For?

Ticagrelor is used for the prevention of atherothrombotic events (heart attack, stroke, cardiovascular death) in patients with acute coronary syndrome (ACS) โ€” including unstable angina, NSTEMI, and STEMI โ€” and in patients with a history of myocardial infarction at high risk.

How Does Ticagrelor Work?

Ticagrelor reversibly binds to the P2Y12 ADP receptor on platelet surfaces, inhibiting ADP-induced platelet aggregation. Unlike clopidogrel (which requires metabolic activation), ticagrelor acts directly and reversibly โ€” producing more consistent antiplatelet effects across patients regardless of CYP2C19 metaboliser status.

How to Take Ticagrelor

Loading dose: 180 mg, then 90 mg twice daily for up to 12 months (in ACS). For long-term secondary prevention (post-MI >12 months): 60 mg twice daily. Must be taken with low-dose aspirin (75โ€“100 mg/day). Do not stop suddenly โ€” always consult your cardiologist before stopping.

Common Side Effects of Ticagrelor

  • Dyspnoea (breathlessness โ€” occurs in up to 15% of patients; not usually associated with cardiac disease)
  • Bleeding (bruising, prolonged bleeding from cuts)
  • Headache
  • Dizziness
  • Nausea

Serious Side Effects โ€” Seek Medical Attention

Contact your doctor or call 111 immediately if you experience any of the following:

  • Serious or fatal bleeding (GI bleeding, intracranial haemorrhage)
  • Bradycardia (transient โ€” particularly at initiation)
  • Ventricular pauses (transient โ€” caution in patients with sinus node disease)
  • Uric acid increase (may precipitate gout)

Drug Interactions

Ticagrelor may interact with other medicines. Always inform your doctor and pharmacist of all medications you are taking. Key interactions include:

  • Strong CYP3A4 inhibitors (ketoconazole, clarithromycin, ritonavir โ€” increase ticagrelor levels โ€” bleeding risk)
  • Strong CYP3A4 inducers (rifampicin, carbamazepine โ€” reduce efficacy)
  • NSAIDs and other antiplatelets/anticoagulants (increased bleeding risk)
  • Simvastatin and lovastatin >40 mg/day (increased statin toxicity)
  • Digoxin (increased digoxin levels)

New Zealand Prescribing Information

Ticagrelor (90 mg tablets โ€” Brilintaยฎ) is funded by Pharmac under Special Authority following ACS. PLATO trial data demonstrated superiority of ticagrelor over clopidogrel in reducing cardiovascular death, MI, and stroke in ACS. The dyspnoea side effect (breathlessness not related to cardiac disease) should be distinguished from worsening heart failure โ€” cardiologist review is warranted if uncertain.

Frequently Asked Questions

Why does ticagrelor cause breathlessness?

Up to 15% of patients experience ticagrelor-induced dyspnoea โ€” a transient breathlessness unrelated to cardiac or respiratory disease, thought to be due to adenosine accumulation (ticagrelor inhibits adenosine reuptake). It usually resolves over days to weeks. However, any new breathlessness after ACS must be investigated to exclude cardiac causes.

Can I switch from ticagrelor to clopidogrel?

Switching from ticagrelor to clopidogrel may be appropriate if breathlessness or bleeding is problematic. This should only be done under cardiologist guidance โ€” the transition timing and loading dose of clopidogrel need to be carefully managed to maintain antiplatelet protection.

Reviewed by a Registered Pharmacist NZ

References & Further Information

The following New Zealand and international resources were used to inform this page:

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