What is the onset and degree of platelet inhibition achieved with a 90 mg loading dose of Brillinta (ticagrelor)?

Platelet Inhibition with 90 mg Ticagrelor Dose

A 90 mg dose of ticagrelor is the maintenance dose, not a loading dose, and achieves peak platelet inhibition approximately 2 hours after administration, with levels of inhibition exceeding those obtained with clopidogrel loading doses. 1

Clarification on Dosing

• The standard loading dose of ticagrelor is 180 mg, not 90 mg 1
• The 90 mg dose represents the maintenance dose given twice daily after the initial loading dose 1
• If you are specifically asking about a 90 mg dose (rather than the standard 180 mg loading dose), this would represent either a maintenance dose or a non-standard reduced loading approach 1

Onset and Degree of Platelet Inhibition with 90 mg Maintenance Dose

Timing of Peak Effect

• Peak inhibitory effect occurs approximately 2 hours after a 90 mg maintenance dose 1
• Ticagrelor achieves platelet inhibition within 30 minutes that exceeds levels obtained with 300-600 mg clopidogrel loading doses 1

Degree of Inhibition

• The 90 mg maintenance dose produces potent and consistent platelet inhibition, with significantly less variability compared to clopidogrel 1, 2
• Ticagrelor does not require hepatic conversion to an active metabolite, resulting in more predictable antiplatelet effects 1, 2

Standard Loading Dose (180 mg) for Comparison

For context, the standard 180 mg loading dose:

• Achieves platelet inhibition within 30 minutes 1
• Reaches peak effect at approximately 2 hours 1
• Produces greater and more rapid platelet inhibition than clopidogrel 300-600 mg loading doses 1

Clinical Considerations

When 90 mg Alone Might Be Used

• In patients already on maintenance ticagrelor therapy who require additional dosing before a procedure, a 180 mg loading dose (not 90 mg) provides more potent and prompt platelet inhibition compared to continuing the 90 mg maintenance dose 3
• If a patient is already on ticagrelor maintenance therapy and requires a procedure, administering an additional 180 mg loading dose achieves significantly lower platelet reactivity compared to just giving the standard 90 mg maintenance dose 3

Pharmacodynamic Profile

• Ticagrelor is a reversible P2Y12 inhibitor with a plasma half-life of approximately 12 hours, requiring twice-daily dosing 1
• Platelet function recovers faster after discontinuation compared to clopidogrel due to reversible binding 1, 2
• Wait at least 5 days after the last dose before surgery to allow adequate recovery of platelet function 1, 2

Important Caveats

• The aspirin dose used with ticagrelor should not exceed 100 mg daily, as higher aspirin doses may reduce ticagrelor's efficacy 1
• Ticagrelor causes dyspnea in 10-15% of patients, typically within the first week of treatment 1, 2
• Ticagrelor is a P-gp inhibitor and can increase levels of concomitant medications like dabigatran 1