Rihanna has been battling illness throughout her 777 Tour.
The singer – who plays her final show of the seven dates in New York on Tuesday - has been relying on a mixture of cough syrup and lozenges to keep her going since waking up with a cough after her first performance in Mexico City last Wednesday.
Speaking in a behind the scenes video, she said: "I woke up coughing on the plane and I took some cough syrup, some cold and sinus tablets, lozenges ... I'm drinking lots of water and [multivitamin supplement] Berocca.
"This entire trip, in order to make it to the end, you have to literally nurse yourself every step of the way the entire time.
"Because it's so much work - so much on your body and so much on your immune system it weakens you. And you're open to so many other viruses that are just there."
Rihanna also worried about the effect viruses would have on the 150 journalists and fans - who have joined her travelling the globe on a private 777 Boeing jet from Mexico City, to Los Angeles, Toronto, Stockholm, Paris, Berlin, London and finally the Big Apple.
In the video, shot earlier in the tour, Rihanna added: "There's so many people on the plane. One flight alone is bad enough, seven of them... We'll definitely be sharing some flu's on this plane.
"I know that sounds gross but that's life. So everybody just has to make sure that they pay attention to themselves and their health throughout."
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