The amount of medication you need does not depend on body weight or on the severity of your symptoms, but rather, what works for you. That is why you may need to re-assess periodically if your medication is still functioning at optimum effectiveness. Many students come to college on the same dose of medication that worked for them in elementary or high school. That's fine if that determination has been made after a recent, careful review of your needs as well as the continued effectiveness of that particular dosage level. It is illegal to share your prescription medication.
Stimulant medications are controlled substances.
You should not transfer your stimulant medication to another bottle for any reason. It is against the law for you to distribute a controlled substance. This means sharing your medication with a friend who needs to study for that big test or concentrate in class or on the playing field is illegal. Many students carry their medications with them at all times to avoid leaving them unattended in their rooms, where they may be more accessible to others. Stimulants do not mix with drugs or alcohol.