If it is MS Contin, I doubt you will feel side effects, although everyone is different in how they process narcotics. I take 15-30 mg (this is a low dosage) at night before bed. I don't feel any side effects and it keeps me from waking in pain. I used to have a problem with waking in pain.

The low-dose MS contin and my Temperpedic mattress help me to sleep well, and I feel rested in the morning.

P.S. 15 mg is the lowest dosage available.