What Is Precipitated Withdrawal?
Question by sexyback: What is precipitated withdrawal?
I am currently studying treatment of opioid dependence, currently in a pharmacy course. Please explain in detail in regards to this theme. Thanks
Best answer:
Answer by AJ
Precipitated withdrawal occurs when an antagonist is given to a person who already has taken opiates/opioids and has these opioids bound to the receptor. I’ll give you an analogy that I gave to another guy asking a similar question:
[Pasted from my previous answer to the question “How does Narcan work?”]
In order to understand this you need to be familiar with receptor theory. There exist throughout the brain and body, various receptors that are activated/transduced by certain chemicals, drugs or otherwise. When a receptor is activated, certain intracellular events take place that lead to some sort of physiological action taking place.
Simply put, if you activate the opioid recceptors, you will get analgesia, euphoria, respiratory depression etc.
Opioid drugs are usually classified as Agonists (eg. Morphine, Heroin), Antagonists (eg Narcan), Partial Agonists (eg. Buprenorphine) and Mixed Agonists/Antagonists (eg. Stadol).
Looking purely at opioids, an agonist binds to the receptor, activates the receptor and then pulls out. This leads to analgesia and subjective opiate effects. An antagonist binds to the receptor, but does not do anything at all. It sits there, preventing any other molecule from activating the receptor. Think of a key and lock. The lock would be the receptor. Morphine for example is like taking the key, sticking it into the receptor and opening the lock (activating the receptor). Narcan on the other hand is like sticking the key into the receptor, not turning the key, but breaking the key across the bridge. So nothing else can activate the receptor.
When Narcan is given to someone who is on opioids or who has overdosed on opioids, it will bind to the receptor and kick off all the other opioids (heroin, fentanyl, morphine etc) off the receptor. This will reverse the action that these drugs cause and put the patient in withdrawals so the patient recovers.
[End Paste]
Now since you say that you are studying opioid dependence treatment, you will need to know the pharmacology of the drug Buprenorphine (Subutex/Suboxone/Buprenex/Temgesic).
Buprenorphine on its own, produces no more of an analgesic effect than the equivalent of say 20-40mg of parenteral Morphine. However, Buprenorphine binds to the opioids with very high affinity. It’s affinity is even higher than that of Naloxone (Narcan) and Naltrexone. So if a patient has taken opioids, and the opioids are still bound to the receptor, Buprenorphine will displace it. If your patient is tolerant to say 120mg of Morphine, and the morphine is kicked off the receptor and replaced with another drug that gives you the equivalent of no more than 20mg of Morphine, you will see that this is no different than simply injecting the patient with Narcan.
Precipitated withdrawals with Narcan only last 15 minutes, but with Buprenorphine, depending on the dosage, it can last up to 3 days. It is intensely painful and extremely uncomfortable!
This is what precipitated withdrawal is about, in the context of opioid dependence treatment. I hope this wasn’t too long and dull for you. If you want, feel free to message me and I’ll try and simplify.