I think you should ask yourself: "What is the purpose of scrubs?".
Usually scrubs are worn in a hospital setting because nurses and doctors deal with various fluids (bodily and chemical) that they do not want on their clothes. Another reason is: wearing your clothes from the outside can potentially carry outside bugs, and changing into clean scrubs once in the hospital, or clean room, can help reduce bringing in particles or bugs. Unless you are working in compounding (where your clothes are likely to get stained), an OR satellite pharmacy, or a clean room, I do not see the purpose of scrubs. If you are starting a new job, and you know that other pharmacists are wearing a shirt and tie, then you should too. You want to give a good first impression. Maybe ask about dress code prior to starting. I wouldn't just ask "Can I wear scrubs?" right off the bat.