| Mechanical | Pharmacologic | Other |
| Abdominal pressure | Histamine-releasing drugs:morphine, codeine, oxycodone, atracurium |
Pain |
| Postural changes | Sympathomimetic agents: ephedrine, epinephrine, norepinephrine, ketamine |
Anxiety/stress |
| Positioning | Dopamine antagonists: metoclopramide, droperidol |
Urination |
| Tyramine-containing foods | Induction of anesthesia | |
| SNRIs/SSRIs/MAO-Is |