By Lauren Smith

Last updated: 21 March 2024 & medically reviewed by Dr. Jenni Jacobsen

Percocet contains the powerful opioid oxycodone, and doctors recommend patients take the lowest effective dose for the shortest duration possible. Taking too much Percocet leaves you at risk of unpleasant side effects, including drowsiness, nausea, and confusion, as well as opioid overdose and liver damage from the acetaminophen in the drug.

Key takeaways:

  • Percocet treatment is initiated at the lowest dose (2.5mg/325mg), with one or two tablets given every 6 hours as needed. The dose can then be increased if the patient continues to have pain.

  • The CDC warns that higher doses of opioids haven’t been shown to provide better pain relief than lower doses and can cause overdoses.

  • People who abuse Percocet may take significantly more than the prescribed dosage, particularly if they’ve abused opioids for a while and have a high tolerance for them.

What is a normal dose of Percocet?

Percocet is a combination of the opioid oxycodone and the over-the-counter painkiller acetaminophen (paracetamol). It’s prescribed for pain after surgery and injuries, for cancer pain, and occasionally for chronic pain when other drugs haven’t been sufficient or can’t be tolerated.

It’s available in four different strengths:[1]

  • 2.5mg oxycodone/325mg acetaminophen

  • 5mg oxycodone/325 mg acetaminophen

  • 7.5mg oxycodone/325mg acetaminophen

  • 10mg oxycodone/325mg acetaminophen

Treatment is initiated at the lowest dose (2.5mg/325mg), with one or two tablets given every 6 hours as needed. The dose can then be increased if the patient continues to have pain.

The usual adult dosage of Percocet is:

  • 2.5mg/325mg: 1-2 tablets every 6 hours as needed for pain

  • 5mg/325mg: 1 tablet every 6 hours as needed

  • 7.5mg/325mg: 1 tablet every 6 hours as needed

  • 10mg/325mg: 1 tablet every 6 hours as needed

The dosing is determined for each patient based on the severity of their pain, previous experience with painkillers, and their vulnerability to opioid abuse and substance use disorder. In general, the lowest effective dose should be used for the shortest duration of time possible.[2]

What is the highest dose of Percocet?

The maximum daily dose of Percocet, as prescribed is as follows:[2]

  • 2.5mg/325mg: 12 tablets

  • 5mg/325mg: 12 tablets

  • 7.5mg/325mg: 8 tablets

  • 10mg/325mg: 6 tablets

The CDC warns that higher doses of opioids haven’t been shown to provide better pain relief than lower doses and can cause overdoses. Doses of about 50 morphine milligram equivalents (MME) per day are associated with double the risk of overdose compared to doses below 20 MME/day.[3]

The risky 50 MME is 33mg of oxycodone or

  • 13 pills of 2.5mg/325mg Percocet per day

  • 6.5 pills of 5mg/325mg Percocet per day

  • 4.5 pills of 7.5mg/325mg Percocet per day

  • 3 pills of 10mg/325mg Percocet per day

These doses elevate the risk of overdose, even if prescribed. Patients should take the lowest dose possible to minimize these risks.

Additionally, the total daily dose of acetaminophen should not exceed 4g per day (12 Percocet pills) due to the risk of liver damage.[2]

People who abuse Percocet may take significantly more than the prescribed dosage, particularly if they’ve abused opioids for a while and have a high tolerance for them.

What are the side effects of high doses of Percocet?

Higher doses increase the risk of side effects from the oxycodone in Percocet, which include:[4]

  • Nausea and vomiting

  • Constipation

  • Drowsiness

  • Dizziness

  • Feeling faint

  • Confusion

  • Itchiness

  • Stomach discomfort/abdominal pain

High doses of Percocet can also cause an opioid overdose, which can be fatal and requires immediate medical attention. Symptoms of overdose include:[5]

  • Slow and shallow breathing (respiratory depression)

  • Severe drowsiness, inability to talk, or unconsciousness

  • Blue or gray skin color, dark lips, and fingernails

  • Irregular heart rate

  • Snoring or gurgling noises

High doses of acetaminophen—exceeding 4g (4,000mg) in 24 hours or 12 Percocet tablets—can cause severe liver damage. If you’re also drinking alcohol, just 2g of acetaminophen (6 Percocet) can damage your liver. In the United States, 1600 cases of acute liver failure each year occur as a result of acetaminophen overuse, with 500 people dying.[6]

Symptoms of acute liver failure include:[7]

  • Jaundice (yellowing of the skin and eyeballs)

  • Acute pain in the upper right abdomen

  • Ascites (swollen abdomen)

  • Nausea and vomiting

  • Malaise (general sense of being unwell)

  • Disorientation, confusion

  • Sleepiness

  • Musty or sweet odor on the breath

  • Tremors

Percocet drug interactions

Many medications may interact with Percocet/oxycodone and should not be taken alongside it. Common interactions include:[8]

  • Other opioids can increase the side effects and increase the risk of overdose. These include other sources of oxycodone (eg. OxyContin), hydrocodone (eg. Vicodin, Lortab, Lorcet), morphine, codeine, fentanyl, methadone, and tramadol. Learn more about Percocet vs other opioids.

  • Other central nervous system (CNS) depressants such as benzodiazepines (e.g. Valium, Ativan, Klonopin, Xanax), sleep medications (e.g. Ambien and Lunesta), sedating antihistamines such as diphenhydramine (Benadryl), muscle relaxants (e.g. baclofen and cyclobenzaprine), and barbiturates. These drugs compound the CNS depression caused by Percocet and can lead to clumsiness and drowsiness and in severe cases, respiratory distress, deep sedation, low blood pressure, coma, and death.

  • Opioid antagonists block the effects of opioids, such as naltrexone and naloxone (Narcan). These may be administered to reverse an opioid overdose or prevent opioid abuse but will render Percocet ineffective if you’re legitimately and safely taking it for pain.

This list of drug interactions is not complete. You should use a drug interaction checker or, ideally, speak to your doctor or pharmacist before beginning Percocet if you’re taking other medications and supplements.

Percocet can also interact with common beverages:[9]

  • Alcohol: compounds the CNS depression caused by oxycodone and the liver damage caused by acetaminophen

  • Grapefruit juice: slows the metabolism of oxycodone and increases the plasma concentration of oxycodone, leading to greater side effects and increasing the risk of overdose.

Percocet risks and warnings

When taken at low doses for short periods of time and for legitimate pain (for example following surgery), Percocet is safe. However, improper use can be very dangerous.

Potential hazards of Percocet include:

  • Dizziness, confusion, drowsiness, and shallow/slow breathing, which may be more pronounced in older adults.

  • Sleepiness and poor motor control, which means you shouldn’t drive or operate heavy machinery while taking Percocet.

  • Overdose can occur even at the upper end of the recommended doses, depending on the patient’s opioid tolerance, body weight, and metabolism.

  • Interaction with common medications and alcohol (see above.

  • Allergic reactions to either oxycodone or acetaminophen, causing itching/swelling of the face, tongue, and throat, and trouble breathing.

  • Addiction: the American Medication Association (AMA) estimates that 3% to 19% of patients prescribed opioid pain medications like Percocet develop addictions to them.[10]

This isn't a complete list of risks and warnings. For further information, read the leaflet that came with your prescription or speak to a doctor or pharmacist.