United Kingdom, March 8 -- Jack Antonoff feels "allergic" to drugs following a life-changing experience after the death of his sister.

The Bleachers frontman - who is married to Margaret Qualley - was 18 years old when his sibling Sarah died of brain cancer aged just 13 and although at the time he and his friends had been experimenting while touring with his band Steel Train, one night his grief combined with the effects of psychedelic mushrooms saw him get "completely freaked out" and he pledged never to dabble again.

Speaking to Apple Music's Zane Lowe, he said: "We were touring a lot and I was obviously just so [messed] up emotionally that I took a whole bunch of mushrooms one night with some friends and I completely freaked out.

"I...