OxyContin is roughly 1.5 times stronger than morphine on a milligram-for-milligram basis when taken by mouth. That makes it one of the more potent prescription opioids commonly used for pain, though it falls well below fentanyl, which is approximately 60 to 100 times stronger than oxycodone (the active ingredient in OxyContin). For someone without opioid tolerance, a single dose above 40 mg can cause fatal breathing suppression, which gives a concrete sense of how powerful this drug is even at relatively small amounts.
How OxyContin Compares to Other Opioids
Doctors measure opioid strength using a standard called morphine milligram equivalents (MME), which treats oral morphine as the baseline. By that scale, 1 mg of oxycodone equals 1.5 mg of morphine. So a 20 mg OxyContin tablet delivers pain relief equivalent to 30 mg of oral morphine.
Compared to hydrocodone (the opioid in Vicodin), oxycodone is modestly stronger. Clinical data from cancer patients found a conversion ratio of about 0.9, meaning roughly 9 mg of hydrocodone provides pain relief similar to 10 mg of oxycodone. The difference is small enough that the two drugs are sometimes grouped together as “moderate-strength” opioids, but oxycodone consistently edges ahead in potency.
Fentanyl sits in a different category entirely. The standard conversion puts fentanyl at 100 times the strength of morphine, which works out to roughly 60 to 70 times stronger than oxycodone. One clinical study comparing the two drugs directly in post-surgical patients found that 11.5 mg of oxycodone provided similar relief to 0.184 mg of fentanyl, a ratio of about 1 to 62. That gap explains why fentanyl is typically reserved for severe pain or patients who have already built tolerance to other opioids.
Why It Hits Harder Than Its Binding Suggests
Oxycodone’s clinical strength is somewhat surprising given its basic chemistry. At the receptor level, oxycodone actually binds to the brain’s primary opioid receptor 5 to 40 times more weakly than morphine does. The reason it still outperforms morphine in practice comes down to how efficiently the body absorbs it. When you swallow morphine, only about 30% of the dose reaches your bloodstream. Oxycodone’s oral absorption is significantly higher, so more of the drug makes it to the brain despite its weaker receptor grip.
OxyContin is specifically designed as an extended-release tablet, meaning a single dose releases oxycodone gradually over 12 hours. Pain relief typically begins within one hour, with blood levels peaking around three hours after swallowing the tablet. That slow, sustained release is what separates OxyContin from immediate-release oxycodone products, which hit faster but wear off in four to six hours.
Available Tablet Strengths
OxyContin comes in seven tablet sizes: 10 mg, 15 mg, 20 mg, 30 mg, 40 mg, 60 mg, and 80 mg. Converting those to morphine equivalents, the range spans from 15 MME at the lowest dose to 120 MME at the highest. For perspective, the CDC flags 50 MME per day as a threshold where risks begin to outweigh benefits for most patients. That means even a single 40 mg OxyContin tablet (60 MME) already crosses that line.
The 60 mg and 80 mg tablets carry an explicit FDA warning: they are approved only for patients who have already developed tolerance to opioids. For someone without that tolerance, those doses can slow breathing to a fatal degree.
Where the Danger Threshold Sits
The FDA labels any single dose above 40 mg, or any total daily dose above 80 mg, as potentially fatal for opioid-naive individuals. “Opioid-naive” means anyone who hasn’t been taking opioids regularly enough to build physical tolerance, which includes most people picking up a prescription for the first time.
CDC guidelines reinforce this caution from a different angle. At or above 50 MME per day (equivalent to about 33 mg of oxycodone daily), the agency recommends extra safety measures, including more frequent follow-up visits and providing naloxone, the overdose-reversal medication, to the patient and their household. Beyond that level, additional dose increases yield progressively less pain relief while steadily increasing the risk of respiratory depression, sedation, and dependence.
The Reformulated Tablet’s Physical Strength
People searching “how strong is OxyContin” may also be curious about the tablet itself. Since 2010, OxyContin has been manufactured with abuse-deterrent technology that makes the physical tablet remarkably resistant to tampering. Crushing the reformulated tablet requires significantly more force than the original version, and even when crushed, it breaks into large fragments rather than fine powder. If those fragments are mixed with water, they form a thick gel that cannot be drawn into a syringe or snorted. This design prevents the most dangerous form of misuse: defeating the extended-release mechanism to get the full 12-hour dose all at once.
The reformulation doesn’t change OxyContin’s strength when taken as prescribed. A 40 mg tablet still delivers the same amount of oxycodone over the same 12-hour window. What it changes is how difficult it is to convert that slow-release dose into an immediate, concentrated hit.