Katrina Kaif collapsed on the sets of Farah Khan's Tees Maar Khan on Wednesday while shooting at Malshej Ghat, about 100 km away from here.

Co-star Akshay Kumar flew in a doctor from city-based Breach Candy Hospital in his private chopper since the medical facilities in Malshej were below par.

The doctor listed over exertion, lack of sleep and her constant low blood pressure as causes of the collapse.

Her spokesperson confirmed the incident. "Katrina was unwell on Wednesday morning. She has been advised some rest. Of late, she has been going through tremendous work stress travelling in and out of Mumbai."

According to sources on the sets, "Katrina has been shooting non-stop for her films and commercials. The constant travel is taking a toll on her health. Katrina's plate is so full this year that she hasn't had enough time to recuperate."