Prescription sleeping medication can be habit-forming, and many side effects are undesirable. They can interfere with normal breathing and can be dangerous in people who have certain chronic lung problems such as asthma, emphysema, or forms of chronic obstructive pulmonary disease (COPD). If you notice any of these side effects, consult your doctor immediately. They may be able to suggest a lower dose, a different medication, or a plan for slowly weaning off the medication.