Percocet contains two active ingredients: oxycodone, a prescription opioid painkiller, and acetaminophen, the same over-the-counter pain reliever found in Tylenol. Every Percocet tablet has 325 mg of acetaminophen paired with one of four oxycodone strengths: 2.5 mg, 5 mg, 7.5 mg, or 10 mg. The combination is prescribed for moderate to moderately severe pain.
The Two Active Ingredients
Oxycodone is the stronger of the two components. It’s a semisynthetic opioid, meaning it’s derived from natural compounds found in the opium poppy but chemically modified in a lab. It works by binding to opioid receptors in the brain and spinal cord, which reduces the excitability of nerve cells that transmit pain signals. This is what gives Percocet its potent pain-relieving effect, but it’s also what makes the drug habit-forming. Oxycodone can produce feelings of euphoria and sedation, especially at higher doses.
Acetaminophen works through a different, less well-understood pathway. Its pain-relieving and fever-reducing effects are partly tied to blocking the production of prostaglandins, chemicals your body releases in response to injury or illness that amplify pain and raise body temperature. Acetaminophen also appears to work through pathways in the brain involving serotonin signaling and certain receptors involved in pain perception. On its own, acetaminophen is a mild to moderate painkiller. Paired with oxycodone, it boosts the overall pain relief, allowing a lower opioid dose to be effective.
Available Tablet Strengths
The acetaminophen dose stays constant at 325 mg across all four tablet strengths. What changes is the amount of oxycodone:
- 2.5 mg / 325 mg (lowest strength)
- 5 mg / 325 mg
- 7.5 mg / 325 mg
- 10 mg / 325 mg (highest strength)
The first number always refers to oxycodone, the second to acetaminophen. Your prescriber chooses the strength based on the severity of your pain and whether you’ve taken opioids before.
Inactive Ingredients and Tablet Colors
Beyond the two active drugs, every Percocet tablet contains a set of inactive ingredients that hold the pill together, help it dissolve properly, and give it its shape. These include microcrystalline cellulose (a plant-based filler), croscarmellose sodium (which helps the tablet break apart in your stomach), povidone (a binder), pregelatinized cornstarch, stearic acid, and colloidal silicon dioxide. Some strengths also contain crospovidone and corn starch.
Each strength is a different color, thanks to specific dyes. The 2.5 mg tablet contains FD&C Red No. 40 Aluminum Lake. The 5 mg tablet contains FD&C Blue No. 1 Aluminum Lake. The 7.5 mg uses FD&C Yellow No. 6 Aluminum Lake, and the 10 mg uses D&C Yellow No. 10 Aluminum Lake. If you have a known sensitivity to any of these dyes, that’s worth mentioning to your pharmacist. Generic versions of oxycodone/acetaminophen may use entirely different inactive ingredients and colorants.
Why the Acetaminophen Matters
The 325 mg of acetaminophen in each tablet can add up quickly if you’re taking multiple doses a day or using other acetaminophen-containing products at the same time. The FDA sets the maximum daily acetaminophen intake at 4,000 mg across all medications combined. Exceeding that threshold risks serious liver damage, and the danger increases with alcohol use. Many common cold medicines, sleep aids, and headache remedies contain acetaminophen, so it’s easy to accidentally double up without realizing it. Checking every label for “acetaminophen” or “APAP” is the simplest way to avoid this.
Controlled Substance Classification
Percocet is classified as a Schedule II controlled substance by the DEA, the same category as fentanyl and methadone. Schedule II drugs are recognized as having legitimate medical uses but carry a high potential for abuse and severe physical or psychological dependence. Because of this classification, Percocet prescriptions cannot be called in by phone in most states, cannot be refilled, and require a new written prescription each time. Pharmacies also keep strict inventory records for every tablet dispensed.
Percocet vs. Other Oxycodone Products
The ingredient that distinguishes Percocet from other oxycodone medications is acetaminophen. OxyContin, for example, contains only oxycodone in an extended-release formulation designed to work over 12 hours. Percocet is an immediate-release tablet, meaning it starts working within 15 to 30 minutes and its effects typically last four to six hours. Other combination products pair oxycodone with ibuprofen instead of acetaminophen, though these are less commonly prescribed.
Counterfeit pills sold as Percocet or marked “M30” have become a significant safety concern. Street-purchased tablets that look like Percocet frequently contain fentanyl or other synthetic opioids instead of, or in addition to, oxycodone. A pill obtained outside a licensed pharmacy has no guarantee of containing what the imprint suggests.