Table 1.

Side effects of therapeutic opioids. Reproduced with permission from Boland et al ³³

System	Effects
Gastrointestinal	Constipation, xerostomia, nausea and vomiting, gastro-oesophageal reflux
Neurological	Delirium, hallucinations, sedation, myoclonus, hyperalgesia, seizures, headaches
Cardiovascular	Bradycardia, hypotension
Pulmonary	Respiratory depression, non-cardiogenic pulmonary oedema
Urological	Urinary retention, altered renal function
Endocrinological	Hypogonadism, sexual dysfunction, osteoporosis
Immune	T cell, natural killer (NK) cell, neutrophil and monocyte dysfunction, cytokine dysregulation (clinical effect unknown)