Naltrexone (Revia): can it be prescribed online?
Naltrexone doesn’t get you sober — it helps you stay sober by muting the reward that alcohol and opioids deliver. It’s one of the best-studied recovery medications we have, but it comes with a critical timing rule: start it too early and it can throw you into sudden, severe withdrawal.
What is naltrexone?
Naltrexone is an opioid antagonist — it sits on the brain’s opioid receptors and blocks them, so alcohol and opioids can’t produce their usual rewarding high. It’s the generic version of Revia (daily pill), and the same medication is available as a once-monthly injection called Vivitrol. It’s FDA-approved for both alcohol use disorder and opioid use disorder.
- FDA-approved for: alcohol use disorder and opioid use disorder (recovery maintenance)
- How it works: blocks opioid receptors, muting the rewarding effects of alcohol and opioids
- Forms: daily pill (Revia) or once-monthly injection (Vivitrol)
- Not a controlled substance: no abuse or dependence potential
Naltrexone is a maintenance medication, not a detox medication — it supports recovery after someone has stopped using. Only a licensed clinician who has evaluated you can determine whether it’s appropriate and when it’s safe to begin.
Can I get naltrexone prescribed online?
Yes, in most cases — but expect a thorough evaluation first. Naltrexone is not a controlled substance, so telehealth prescribing is permitted where state law allows. Because addiction treatment carries real medical stakes, a responsible prescriber will take a detailed history: what substances, how much, when you last used, your liver health, and your support plan. For opioid use disorder especially, the initial evaluation and the timing of the first dose are often handled with in-person care or close coordination.
What’s still required: an honest, complete evaluation. Any site offering naltrexone without understanding your use history should be avoided — getting the timing wrong here is dangerous.
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Find a psychiatristWhat to expect if you’re prescribed naltrexone
The 7-to-10-day rule for opioids
This is the single most important thing about naltrexone: if you have opioid use disorder, you must be completely opioid-free for 7 to 10 days before the first dose. Starting earlier triggers precipitated withdrawal — naltrexone yanks remaining opioids off your receptors all at once, producing sudden, severe withdrawal that can require emergency care. Your prescriber will confirm the timing, sometimes with a test dose or lab work.
It doesn’t treat withdrawal itself
Naltrexone won’t ease shakes, nausea, or cravings of acute withdrawal — that’s what medically supervised detox is for. Naltrexone’s job starts after detox ends: making a slip far less rewarding, which protects the recovery you’ve built.
Pill or monthly shot
The daily pill works only if you take it daily — and skipping is easy when motivation dips. Vivitrol, the monthly injection given by a clinician, removes the daily decision entirely. Many people prefer the shot for exactly that reason; your prescriber can walk through the trade-offs.
Nausea early on, liver checks ongoing
Nausea is the most common early side effect and usually fades. More importantly, your prescriber will check your liver function before starting and periodically afterward, since naltrexone can strain the liver — a real consideration for anyone with alcohol-related liver concerns.
Frequently asked questions
Is naltrexone a controlled substance?
No. Naltrexone isn’t a controlled substance and isn’t habit-forming — it does the opposite of what addictive drugs do at the receptor. It can be prescribed after a proper medical evaluation, including via telehealth where state law allows.
Why must I be opioid-free for 7 to 10 days before starting naltrexone?
Because naltrexone blocks opioid receptors aggressively. If opioids are still in your system, it displaces them all at once and triggers precipitated withdrawal — sudden and severe, sometimes needing emergency care. The waiting period lets your body clear opioids completely first.
Does naltrexone treat opioid withdrawal?
No — and this distinction matters. Naltrexone doesn’t relieve withdrawal symptoms; started too early, it causes them. It’s a recovery-maintenance medication used after detox is finished.
What happens if I use opioids while on naltrexone?
The high is blocked, which tempts some people to take much larger amounts to “break through” — risking fatal overdose. Naltrexone also lowers your opioid tolerance, so the dose you used to handle can kill you after a period on the medication. Never try to override it.
Pill vs. Vivitrol injection — what’s the difference?
Same medication, different delivery: Revia is a daily pill, Vivitrol is a once-monthly injection from a clinician. The shot suits people who struggle with daily adherence or want the decision taken out of their hands each morning. Both require the same opioid-free waiting period before starting.
Does naltrexone require liver monitoring?
Yes. Expect liver function tests before you start and periodically during treatment, since naltrexone can stress the liver. Be upfront with your prescriber about alcohol use and any liver conditions.
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