According to the Lakers, Gasol was diagnosed with vertigo.
Vertigo is often caused by a dysfunction in the inner ear, which helps regulate balance.
An MRI on Monday of Gasol's head came back normal.
The Lakers center/forward will be listed as doubtful for Tuesday night when the Lakers host the New York Knicks.
He'll be examined again on Tuesday morning.
Gasol played just more than 18 1/2 minutes in a 103-94 win over the Orlando Magic, scoring six points with three assists and two rebounds. He didn't come out of the locker room after halftime, falling ill.
Through 59 games, Gasol has averaged 17.5 points, 9.8 rebounds and 3.3 assists.