As a nurse, is it okay to correct a doctor especially in giving out medications?

Absolutely. It is your responsibility to the doctor and the patient to speak up is a correction needs to be made.

If you feel the medication is inappropriate or the dosage is wrong, first check and confirm that with the pharmacy, and usually they will contact the physician themselves so they can answer any questions the Dr will have, and that you might not know. There is no point in you being the middle man-the pharmacy should discuss this with the Dr. It is actually your duty to question anyone writing orders on a patient that are not correct or appropriate.

Hell yeah because you are the last line of defense for that patient. You can say , can you please explain to me what is the purpose of this medication for the patient. But you have that right, go to the Nurse Manager and get their opinion also. Just a thought

Yes absolutely! It's part of the RN's role to ensure the doctor's intentions are carried out. They are counting on us to find mistakes and politely point them out. Maybe a stressed-out doc will react with anger, but they still realize and appreciate that we are a team and protecting each other from grave mistakes.
The first being "Do no harm" the second third and fourth being "Don't get sued."

You are the patient's advocate