Felipe Massa found himself unwell yesterday after free practice, and was taken to a hospital in Budapest for precautionary checks.
The Brazilian was feeling sick and dizzy after yesterday afternoon's second free practice session which he was only 15th fastest.
Massa cancelled his media appearances and was transferred to the MH EK Honvedkorhaz hospital in Budapest for further analysis.
A diagnosis revealed no serious problem and the Williams driver was given the green light Saturday morning by the FIA's medical delegate, declaring the driver fit and well.
Massa will however undergo another check after FP3 later today. Should there be a problem, Williams' official reserve driver and Sky Sports F1 consultant Paul di Resta could step in to replace the Brazilian.
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