Clopidogrel × Ticagrelor

Clopidogrel and ticagrelor block the same platelet receptor, P2Y12. Clopidogrel acts through an active metabolite and binds irreversibly, so affected platelets stay switched off for 7-10 days; ticagrelor binds reversibly and needs no bioactivation. The pair adds no benefit: after a loading dose ticagrelor already suppresses aggregation almost fully, and no trial has tested two oral P2Y12 inhibitors together. ESC 2023 dual antiplatelet therapy is aspirin plus one P2Y12 inhibitor. Bleeding risk, meanwhile, is additive, as both product labels state.

Gum bleeding, epistaxis, bruising and haematomas after minor trauma, melaena, haematuria, a haemoglobin drop with no obvious source. Dyspnoea on ticagrelor is a drug effect of its own and usually has nothing to do with blood loss.

Keep one P2Y12 inhibitor and stop the other the same day. Spacing the doses or halving both makes no sense. For acute-phase escalation, start ticagrelor with a 180 mg loading dose and drop clopidogrel at that moment, the way the 2017 international switching consensus describes it. For an elective switch outside the acute setting the Brilique SmPC gives a different anchor: the first dose 24 hours after the last dose of the other antiplatelet. On ticagrelor keep aspirin maintenance at or below 100 mg daily. Never stop both at once: premature withdrawal of antiplatelet therapy after an acute coronary syndrome raises the risk of infarction and death. After stopping the extra drug watch for bleeding over the next few days, and note that both labels require a 5-day pause before high-bleeding-risk procedures.