Answer
Phenindione itself has no or negligible expected effect on driving, but do not drive if bleeding, dizziness or another adverse effect makes it unsafe.
Sources for this answer
- Dindevan 25mg Tablets / Phenindione 25mg Tablets — Current selected SmPCemc · Summary of Product Characteristics
General medicine information. Follow the instructions for your own medicine and speak to a pharmacist or clinician about your individual circumstances.