When a driver feels **sleepy**, it is crucial to **rest as soon as possible in a suitable place**. This is because drowsiness negatively affects the ability to drive safely.

- **Symptoms of drowsiness** include difficulty keeping the head upright, blurred vision, frequent yawning, loss of concentration, and being easily distracted. These symptoms indicate that the driver is not in optimal condition to continue driving.

- **Causes of drowsiness** can be sleeping less than usual, changes in sleep schedule, driving at times of the day prone to sleepiness such as early morning or after eating, and the consumption of alcohol or certain medications.

- **Preventive measures**: It is advisable to stop the vehicle in a safe place and rest for 20 or 30 minutes when feeling the first symptoms of fatigue. Additionally, it is recommended to rest regularly every two hours or 200 kilometers, even if you do not feel tired.

Therefore, the safest and most appropriate option is to **stop and rest** as soon as you feel sleepy, to avoid accidents and ensure road safety.