If you are taking too much Oxycodone, feeling sleepy is a sign of overdose, be careful with opioids, they are not to be messed with, or any other medication. It most often occurs after taking the medication for one month or longer. Feeling sleepy or tired are common side effects which should subside between 1 week to 10 days, if they persist do contact your Dr. Adrenal Insufficiency: Adrenal insufficiency, or impaired function of the adrenal gland, is a rare but severe side effect of taking this medication.Symptoms can include shivering, agitation, diarrhea, nausea and vomiting, fever, seizures, and muscle function changes. Serotonin Syndrome: This medication can cause a high serotonin level in your body, which in rare cases can lead to serotonin syndrome.

Nausea or Vomiting: Nausea, with or without vomiting, can be a side effect of opioid pain medications.

However, oxymorphone has a significantly longer half life (7-9 hours) than does oxycodone, whose mean elimination half-life following a single, oral dose is 3.51 ± 1.43 hours.

Constipation: Constipation is a widespread side effect of pain medications. Oxycodone is metabolized in part by cytochrome P450 2D6 to oxymorphone, which represents less than 15 of the total administered dose.

Liver Toxicity: This medication can cause liver toxicity.

This adaptation causes tolerance, but it can also cause dependence. Even in cases of a prescription, as a person takes regular doses of opioids, their bodies will begin to adapt to the medications in as little as a week.

Addiction, Tolerance, and Dependence: Opioid medications have addictive properties and are more likely to develop into an addiction when used by people who are not in pain.Sleepiness: Feeling sleepy, tired, or lightheaded may accompany the use of opioid pain medication.Slowed breathing or low blood pressure: This usually only occurs when the medication dose is too high or increased too quickly.Some of the possible side effects include:

Does oxycodone make you sleepy