The M523 pill is commonly identified as a prescription opioid pain medication that contains oxycodone hydrochloride and acetaminophen. More specifically, a white oblong pill marked “M523” on one side and “10/325” on the other is listed as oxycodone hydrochloride 10 mg and acetaminophen 325 mg.
So, is the M523 pill a Percocet? In practical terms, yes, it contains the same active ingredients found in Percocet: oxycodone and acetaminophen. However, “Percocet” is a brand name, while M523 is typically a generic oxycodone-acetaminophen tablet. That distinction matters, but the risks are very similar.
Because M523 contains oxycodone, it is a Schedule II controlled substance with a high potential for misuse, dependence, and addiction. It should only be taken when prescribed by a licensed medical provider and exactly as directed. Taking an M523 pill without a prescription, taking more than prescribed, mixing it with alcohol or other sedatives, or using it to get high can increase the risk of overdose and other serious complications.
What Is the M523 Pill?
The M523 pill is an oxycodone-acetaminophen combination medication. Oxycodone is an opioid pain reliever, while acetaminophen is a non-opioid pain reliever often used to reduce pain and fever. Together, these medications may be prescribed for moderate to moderately severe pain.
The imprint “M523 10/325” generally refers to:
Oxycodone hydrochloride: 10 mg
Acetaminophen: 325 mg
This is considered a stronger oxycodone-acetaminophen tablet compared to lower-dose versions such as 5/325 or 7.5/325. The “10/325” means the pill contains 10 mg of oxycodone and 325 mg of acetaminophen.
M523 Pill at a Glance
| Category | Details |
|---|---|
| Common imprint | M523 on one side, 10/325 on the other |
| Drug type | Prescription opioid pain medication |
| Active ingredients | Oxycodone hydrochloride and acetaminophen |
| Strength | 10 mg oxycodone hydrochloride / 325 mg acetaminophen |
| Similar to Percocet? | Yes. It contains the same active ingredients as brand-name Percocet, but M523 is typically a generic version. |
| Controlled substance status | Schedule II controlled substance |
| Main risks | Misuse, dependence, addiction, overdose, slowed breathing, and liver damage from too much acetaminophen |
| Counterfeit risk | Pills from non-pharmacy sources may be fake and can contain fentanyl or other dangerous substances |
| Safe use | Only take it when prescribed by a licensed medical provider and dispensed by a pharmacy |
| When to seek help | If use feels hard to control, withdrawal symptoms occur, pills are being used to cope emotionally, or there are signs of overdose |
Is M523 the Same as Percocet?
M523 is not usually the brand-name Percocet tablet, but it is a generic version of the same type of medication. Percocet is a brand name for a medication that combines oxycodone and acetaminophen. M523 also contains oxycodone and acetaminophen, which is why many people refer to it as a “Percocet.”
From a safety standpoint, the difference between brand-name Percocet and a generic oxycodone-acetaminophen pill does not remove the risk. Both contain an opioid. Both can cause dependence. Both can be dangerous when misused.
M523 vs. Brand-Name Percocet
| Category | M523 10/325 | Brand-Name Percocet |
| Brand or generic | Typically a generic oxycodone-acetaminophen tablet | Brand-name oxycodone-acetaminophen medication |
| Active ingredients | Oxycodone hydrochloride and acetaminophen | Oxycodone hydrochloride and acetaminophen |
| Common strength discussed | 10 mg oxycodone / 325 mg acetaminophen | Percocet is available in multiple strengths, including oxycodone-acetaminophen combinations such as 2.5/325, 5/325, 7.5/325, and 10/325 |
| Opioid content | Contains oxycodone | Contains oxycodone |
| Acetaminophen content | Contains 325 mg acetaminophen | Contains acetaminophen, usually 325 mg in current Percocet formulations |
| Addiction risk | Yes. Because it contains oxycodone, M523 can lead to misuse, dependence, and addiction. | Yes. Brand-name Percocet carries similar opioid-related risks. |
| Overdose risk | Yes, especially when misused, mixed with alcohol or sedatives, or taken in high doses | Yes, especially when misused, mixed with alcohol or sedatives, or taken in high doses |
| Counterfeit concern | A pill marked M523 from a non-pharmacy source could be counterfeit | Pills sold as “Percocet” outside a pharmacy may also be counterfeit |
| Key takeaway | M523 is commonly treated as a generic Percocet-type pill because it contains oxycodone and acetaminophen. | Percocet is the brand-name version of an oxycodone-acetaminophen medication. |
What Does M523 Look Like?
A legitimate M523 10/325 pill is typically described as a white or off-white, oblong or capsule-shaped tablet. It is debossed with “M523” on one side and “10/325” on the other.
However, appearance alone is not enough to confirm that a pill is safe or legitimate. Counterfeit pills can be made to look like real prescription medications. The DEA has warned that fake pills are often made to resemble prescription opioids such as oxycodone or Percocet, but may contain fentanyl, methamphetamine, or other dangerous substances.
If a pill was not dispensed directly by a licensed pharmacy, there is no reliable way to know what it contains based on the imprint, color, or shape alone.
Why M523 Can Be Dangerous
The main danger of M523 comes from oxycodone, an opioid that affects the brain’s pain and reward pathways. Opioids can cause relaxation, pain relief, sedation, and euphoria, but they can also slow breathing. In high doses, or when mixed with alcohol, benzodiazepines, sleep medications, or other depressants, oxycodone can cause life-threatening respiratory depression.
M523 also contains acetaminophen. While acetaminophen is not addictive, taking too much can damage the liver. This can happen when someone takes multiple oxycodone-acetaminophen pills, combines them with other acetaminophen-containing medications, or uses them with alcohol.
The risks increase when M523 is used outside of medical supervision. Misuse may include crushing, snorting, taking extra doses, using someone else’s prescription, or buying pills from non-pharmacy sources.
Can You Get Addicted to M523?
Yes. Because M523 contains oxycodone, it can be addictive. Oxycodone can lead to physical dependence, tolerance, withdrawal symptoms, and opioid use disorder.
Tolerance means a person may need more of the drug over time to feel the same effect. Dependence means the body has adapted to the drug and withdrawal symptoms may occur when use is reduced or stopped. Addiction, or opioid use disorder, involves compulsive use despite harm, cravings, loss of control, and continued use even when it causes problems at home, work, school, or with health.
Someone can become dependent on oxycodone even when they started with a legitimate prescription. Risk increases with higher doses, longer use, personal or family history of substance use disorder, mental health struggles, trauma, or using the medication in ways other than prescribed.
Signs of M523 Misuse
M523 misuse may look different from person to person. Some warning signs include taking more than prescribed, running out early, seeking pills from multiple sources, crushing or snorting the medication, using it to relax or escape emotions, hiding pill use, or becoming defensive when asked about it.
Physical and behavioral signs may include drowsiness, small pupils, slowed breathing, constipation, nausea, mood swings, poor coordination, withdrawal from family, missed responsibilities, financial problems, and increased secrecy.
A person misusing M523 may also experience withdrawal symptoms when they stop taking it. Opioid withdrawal may include sweating, chills, muscle aches, anxiety, insomnia, nausea, vomiting, diarrhea, runny nose, watery eyes, and strong cravings.
M523 and Counterfeit Pill Risks
One of the most serious risks today is that a pill sold as “Percocet” or “M523” may not actually be oxycodone-acetaminophen at all. Counterfeit pills can be pressed to look like prescription medications. The FDA warns that counterfeit medicines may contain the wrong ingredients, too much or too little active ingredient, no active ingredient, or harmful ingredients.
The DEA has also reported that many fake pills are made to look like prescription opioids, including Percocet and oxycodone, but may contain fentanyl or other substances.
This is why taking a pill from a friend, dealer, online seller, or any non-pharmacy source can be extremely dangerous. Even one pill can contain a lethal amount of fentanyl.
What to Do If Someone Took an M523 Pill
If someone took M523 and is extremely sleepy, hard to wake up, breathing slowly, turning blue or gray, choking, gurgling, vomiting, or losing consciousness, call 911 immediately. These may be signs of an opioid overdose.
Naloxone, also known by the brand name Narcan, can reverse an opioid overdose if given in time. If naloxone is available, it should be used right away while waiting for emergency medical help. More than one dose may be needed, especially if fentanyl or another potent opioid is involved.
If someone is using M523 regularly and wants to stop, they should not assume they have to quit alone. Medical detox and addiction treatment can help manage withdrawal symptoms, reduce relapse risk, and support long-term recovery.
Treatment for M523 or Percocet Addiction
M523 addiction is a form of opioid addiction, and it can be treated. At Phoenix Rising Recovery, treatment focuses on helping people understand the physical, emotional, and behavioral parts of opioid use.
Treatment may include medical support, therapy, relapse-prevention planning, mental health care, group support, and long-term recovery planning. For some people, medication-assisted treatment may also be appropriate as part of a comprehensive care plan.
The goal is not just to stop taking pills. The goal is to help someone rebuild stability, address the reasons substance use continued, and develop healthier ways to manage pain, stress, trauma, cravings, and emotional distress.
When to Reach Out for Help
It may be time to seek help if M523, Percocet, oxycodone, or other opioids are becoming hard to control. Warning signs include using more than intended, trying unsuccessfully to stop, feeling sick without the drug, craving it, hiding use, mixing it with other substances, or continuing to use despite consequences.
Opioid addiction can feel isolating, but recovery is possible with the right support. If you or someone you love is struggling with M523 or Percocet misuse, Phoenix Rising Recovery can help you take the next step toward safety, stability, and healing.
Frequently Asked Questions About the M523 Pill
Is M523 a Percocet?
M523 is not usually the brand-name Percocet pill, but it contains the same active ingredients: oxycodone and acetaminophen. It is commonly considered a generic oxycodone-acetaminophen tablet.
What strength is the M523 pill?
The M523 10/325 pill contains 10 mg of oxycodone hydrochloride and 325 mg of acetaminophen.
Can M523 get you high?
Because M523 contains oxycodone, it can produce euphoria when misused. This is also what makes it addictive and potentially dangerous.
Is M523 addictive?
Yes. M523 contains oxycodone, an opioid with a high potential for misuse, dependence, and addiction.
Can you overdose on M523?
Yes. Taking too much M523, mixing it with alcohol or sedatives, or taking a counterfeit pill can increase the risk of overdose. Opioid overdose can be life-threatening and requires emergency medical attention.
Is it safe to take an M523 pill from someone else?
No. You should never take prescription opioids that were not prescribed to you. A pill from a non-pharmacy source may also be counterfeit and could contain fentanyl or other dangerous substances.
What should I do if I think someone is addicted to M523?
Approach the person with concern rather than judgment. Encourage them to speak with a medical professional or addiction treatment provider. If there are signs of overdose, call 911 immediately.
Sources
- DailyMed. (n.d.). Oxycodone hydrochloride and acetaminophen tablet. U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=60d2b60f-cbc1-4716-9c2a-ffc8292e3c85
- DailyMed. (n.d.). Oxycodone hydrochloride and acetaminophen tablet. U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=77a4aae7-a0cc-4f86-b91f-ec4112c6d3be
- U.S. Drug Enforcement Administration. (n.d.). Fake prescription pills. https://www.dea.gov/factsheets/fake-prescription-pills
- U.S. Food and Drug Administration. (2025, December 8). Counterfeit medicine. https://www.fda.gov/drugs/buying-using-medicine-safely/counterfeit-medicine
- U.S. Food and Drug Administration. (n.d.). Percocet: Prescribing information. https://www.accessdata.fda.gov/drugsatfda_docs/label/2006/040330s015,040341s013,040434s003lbl.pdf