Glycoprotein IIb/IIIa inhibitors are favourable in ST-elevation myocardial infarction (STEMI) patients, and the additional value of early pre-hospital high bolus dose tirofiban has recently been established. The aim of this study was to determine the impact of age on myocardial reperfusion and clinical outcomes of pre-hospital administration of high bolus dose tirofiban. This is a pre-specified sub-analysis of the multicentre, double-blind, placebo-controlled, randomised On-TIME 2 trial and it's open label phase. The primary endpoint was mean residual ST segment deviation 1 h after primary PCI and was evaluated in three age groups. Of the 466 patients in the highest tertile (a parts per thousand yen68 years), median age was 74.4 years (IQR 71.3-78.6 years) and 231 (50%) were randomised to tirofiban. Mean residual ST segment deviation 1 h after PCI was significantly lower in elderly patients pre-treated with tirofiban compared to elderly patients without tirofiban pre-treatment (4.2 +/- 5.2 mm vs 6.4 +/- 7.5 mm, p = 0.001). Furthermore, elderly patients pre-treated with tirofiban had a non-significantly higher rate of 30-day major or minor bleeding compared to elderly patients without tirofiban pre-treatment (14.2% vs 9.0%, p = 0.088). 30-day net adverse clinical events in elderly patients with- or without tirofiban was not significantly different (11.9% vs 15.2%, p = 0.300). The effect of pre-hospital initiation of high bolus dose tirofiban on myocardial reperfusion, as determined by ST-segment resolution is highest in the elderly patients. However, this was associated with a trend towards more bleeding complications, resulting in a balanced clinical effect after 30-day follow-up. Future studies should evaluate whether the elderly STEMI patient may benefit from highly effective and safer antiplatelet therapy.