So can you get a DUI for a prescribed drug in Florida? 
And the answer is yes. If it's a controlled substance, If it's a prescribed substance, and if it affects the way you drive, you can absolutely be arrested for DUI for medication.

Statute 316.193 states that you have to be in actual physical control of a vehicle and be under the influence of alcohol, drugs or a controlled substance. So it is something that a prescribed drug that might have a drowsy effect can put you under the influence. 
Things that you typically see - any kind of painkiller, any kind of sleep medication, Xanax, are the types of prescribed drugs that you are allowed to take that can make you guilty of a DUI.

Now, there always comes a question what if you took it and you were subsequently arrested, how will they know? There's no breathalyzer for a controlled substance. This comes through either a urine or a blood test. Now, if you've been asked to give a urine sample and you give a urine sample and you see that they come back with a positive toxicology report, that may not be the end of the line. If you have a valid prescription you can show that you had a valid prescription, it doesn't necessarily mean that you were under the influence at the time of your arrest. 
So that is another reason why you need an experienced DUI attorney handling your case if you've been arrested for DUI based on the prescribed medication. 

If you have any other questions about DUI cases then you can download my guide "What You Must Know About Your DUI Case Before You Do Anything," and if you've been arrested or your loved one's been arrested then you can download my book "My Loved One Has Been Arrested: What's Next?".