The Scottish resident from Ayrshire was rushed to hospital after eating a plateful of the festive vegetables.
It gives diners not so keen on sprouts another reason to pass on the unpopular vegetable when offered a helping on Christmas Day.
Brussels sprouts are rich in vitamin K, a chemical the body uses to promote blood clotting.
The man, who has not been named, suffered a heart failure after the sprouts interfered with his blood thinning medication.
Doctors at Golden Jubilee National Hospital in Clydebank, West Dunbartonshire, were left stumped by his condition before learning of his above-average Brussels sprout intake.
Consultant cardiologist Dr Roy Gardner said: ‘Patients who are taking anticoagulants are generally advised not to eat too many green leafy vegetables, as they are full of vitamin K, which antagonise the action of this vital medication.’
The case was reported in a festive edition of the Medical Journal of Australia
Jill Young, chief executive of the Golden Jubilee Hospital, said: ‘Whilst we think this is possibly the first-ever festive admission to hospital caused by the consumption of Brussels sprouts, we were delighted that we were able to stabilise his levels.’