The call came in to Los Angeles County fire at 10:15 a.m. in Los Angeles, KABC-TVreports.
Lohan is currently filming Elizabeth Taylor bio-pic "Liz & Dick" for Lifetime in the Marina del Rey area.
At first, officials said she had been taken to the hospital, but that apparently was not the case.
According to a spokesperson, "Lindsay worked a grueling schedule the past few days. She worked through the night until 8 am this morning. She took a nap before shooting her final scene."
Producers became concerned when she did not come out of her room and called paramedics as a precaution. Lohan was examined, and it was determined that she suffered some exhaustion and dehydration.
She was resting now and hoped to be back on set later this afternoon, the spokesman said.
Lohan, 25, has been to rehab multiple times for drug and alcohol abuse. In March, she was taken off probation stemming from her 2007 DUI case. She has maintained that she is not drinking or using drugs
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