Instagram fail ... Lindsay Lohan posted the bathroom pic of her wearing skimpy Calvin Klein underwear. Picture: Karwai Tang Source: Getty Images

The virus-stricken star posted the bathroom pic of her wearing skimpy Calvin Klein underwear yesterday, trying to make light of her untreatable illness.

But fans soon began voicing their suspicions about Lohan’s ultra thin waist.

STAR STRUCK: Lindsay Lohan contracts rare, incurable virus

Suspicious ... bottles on the sink to the right of the actor seem weirdly slanted. Picture: Instagram/Lindsay Lohan Source: Supplied

The evidence for the Photoshop fakery, they claim, were a set of bottles on the sink to the right of the actor that were weirdly slanted.

“Photoshopped. You can tell by the soaps and shampoos,” wrote worldoftaylor.

The 28-year-old Mean Girls star captioned the picture: “#mycalvins are helping me fight off my chikungunya ?? hehe.”

This is a reference to Chikungunya, a rare virus transmitted through mosquito bites that Lohan caught during a winter break holiday to the French Polynesian island of Bora Bora.

Backlash ... Lindsay Lohan’s followers were quick to pick up ‘distortions’ in the selfie. Picture: Instagram/Lindsay Lohan Source: Supplied

Lohan went there after wrapping up a two-month run on London’s West End in Speed-the-Plow.

The star is not the only one caught out Photoshopping pics.

Beyonce, John Mayer and Tara Reid have all been accused of doctoring social media snaps in the past.