必要な時にだけこの薬をお飲みくださいって英語でなんて言うの？

Question

Only when you need this medisene,please
take it. 薬の頓服

Accepted Answer

必要な時に使う：as needed

\"必要な時にだけこの薬をお飲みください\"
- Please take this medicine as needed. 
- Take this medicine as needed.

Only when you need this medisene,please
take it. 
-> Please take this medicine only when you need it.