Shawn Mendes' skin ''always breaks out'' when he goes on tour.

The 19-year-old singer has admitted at the beginning of every string of musical concerts he goes on his face will be covered in spots because of stress.

Speaking to PEOPLE about his reaction to the intense schedule, he said: ''I'll always break out in the beginning of a tour because I'm always stressed trying to get things perfect.''

But it isn't until the 'Stitches' hitmaker is half way through his tour that the blemishes begin to reduce in size.

He explained: ''Halfway through the tour my skin starts to calm down because my stress levels come down.''

And the musician believes the key to getting rid of the acne outburst is by not looking or touching the pus-filled bumps, as he always finds the instant is even thinks about spots he gets one.

Speaking about his skincare remedy, he said: ''To be honest, I used to use a lot of products and pimple things on my skin. But I feel the more you stare at [pimples] in the mirror, it's not going to go away. My skin is clear when I haven't thought about it and the second I start thinking about it, I'll break out right there! It's so emotion-based.''