DXM misuse can cause:
- loss of coordination
- feeling sick to the stomach
- increased blood pressure
- faster heart beat
- vision changes
- slurred speech
- feeling very excited
- in rare instances when DXM is taken with decongestants, lack of oxygen to the brain, creating lasting brain damage
Promethazine-codeine cough syrup misuse can cause:
- slowed heart rate
- slowed breathing (high doses can lead to overdose and death)
Cough and cold medicines are even more dangerous when taken with alcohol or other drugs.
Long-term effects of cough and cold medicines are not known.