With opiates it’s not the stomach letting the brain know it’s going to throw up, but rather it’s the brain directing the stomach to throw up.

The brain detects opiates in your bloodstream and thinks it is a potential life-threatening situation. The brain says, “Oh no, this isn’t good, these opiates have to go.” So the brain directs the stomach to become nauseous.

Nausea is unpleasant, and its primary purpose is to make you vomit. When you become nauseous, you will likely be salivating, sweating, and your heart will race. These distressing effects are the reasons why you throw up.

Furthermore, there is an actual cycle to throwing up. (1) You detect a problem, such as opiates in the bloodstream; (2) you become nauseous (sweaty, a little weak, high pulse, etc..); and (3) you throw up. Of course, it doesn’t always work this way. High dose opiate use can cause spontaneous vomiting and then nausea. We also know that mixing opiates with other drugs increases the risk of vomiting.


What causes nausea?

nauseousNausea is a normal function of the “area postrema” (AP). The AP is anatomically positioned to detect toxins, because it does not have a Blood-Brain-Barrier. When the AP senses toxins, such as opiates in the blood, it tells the stomach to prepare to throw up. The specific mechanisms of opiate-induced nausea and vomiting (OINV) are still not entirely certain, but it does appear that stimulation of the AP is the main cause of OINV.


Area Postrema (AP)

The AP, in the medulla oblongata, responds to bloodborne stimuli, such as drugs, bacterial toxins, uremia, and hypoxia.

SECTION D – Medulla Oblongata

SECTION 17 – Area Potrema


NOTE: The AP is not responsible for all types of nausea and vomiting. The AP has nothing to do with motion-sickness, because there are no toxins involved in motion sickness.


Treatment for Nausea

Immediately stop taking opiates would be the first line of defense.