Hello, there can be few reasons for voice change. Firstly it could be the side effect of the drug, but that needs you to check with your psychiatrist. Secondly do you use voice excessively like singing, teaching or as call centre etc if yes that can lead to thickening of vocal cord causing voice change. Also hormone disturbance can cause voice change.
Next Steps
Firstly clarify from your psychiatrist and then consult an ENT surgeon online or near your place
Health Tips
1. Start steam inhalation
2. Give voice rest
3. Avoid spicy oily and sour foods