Signs and symptoms of prescription drug abuse depend on the specific drug. Because of their mind-altering properties, the most misused prescription drugs are: 
Opioids used to treat pain, such as medicines containing oxycodone (Oxycontin, Percocet) and those containing hydrocodone (Norco)
Anti-anxiety medicines, sedatives and hypnotics used to treat anxiety and sleep disorders, such as alprazolam (Xanax), diazepam (Valium) and zolpidem (Ambien)
Stimulants used to treat attention-deficit/hyperactivity disorder (ADHD) and certain sleep disorders, such as methylphenidate (Ritalin, Concerta, others), dextroamphetamine-amphetamine (Adderall XR, Mydayis) and dextroamphetamine (Dexedrine)
 Signs and symptoms of prescription drug abuse Opioids 
Constipation
Nausea
Feeling high
Slowed breathing rate
Drowsiness
Confusion
Poor coordination
Increased dose needed for pain relief
Worsening or increased sensitivity to pain with higher doses
 Anti-anxiety medicines and sedatives 
Drowsiness
Confusion
Unsteady walking
Slurred speech
Poor concentration
Dizziness
Problems with memory
Slowed breathing
 Stimulants 
Increased alertness
Feeling high
Irregular heartbeat
High blood pressure
High body temperature
Reduced appetite
Insomnia
Agitation
Anxiety
Paranoia
 Other signs 
Forging, stealing or selling prescriptions
Taking higher doses than prescribed
Being hostile or having mood swings
Sleeping less or more
Making poor decisions
Being unusually energetic, high or revved up
Being drowsy
Requesting early refills or continually "losing" prescriptions, so more prescriptions must be written
Trying to get prescriptions from more than one prescriber
