Understanding Medications: What is a blue pill with a 51 on it?

October 7, 2025 •

4 min read

The Drug Enforcement Administration classifies Oxycodone, the substance found in a blue pill with a 51 on it, as a Schedule II controlled substance due to its high potential for abuse and dependence. Accurate pill identification is vital for safety, as mistaking this potent opioid analgesic could have serious consequences. This medication is used to manage moderate to severe pain and is manufactured by Actavis.

Quick Summary

This guide identifies the round, blue pill marked 'A 51' as Oxycodone Hydrochloride 30 mg, a powerful opioid analgesic for severe pain. It covers its pharmacological effects, approved uses, potential side effects, and critical risks, including addiction, misuse, and life-threatening respiratory depression. Learn about safe use and proper handling for this controlled medication.

Key Points

Identification: The blue, round pill with the 'A 51' imprint is Oxycodone Hydrochloride 30 mg.
Purpose: It is a powerful opioid pain medication prescribed for moderate to severe pain.
High Risk: Classified as a Schedule II controlled substance, indicating a high potential for abuse, addiction, and dependence.
Serious Side Effects: Can cause severe adverse reactions, most notably life-threatening respiratory depression and overdose.
Safety: Proper storage in a secure location and safe disposal are critical to prevent misuse and accidental ingestion.
Misuse Dangers: Taking more than prescribed or for non-medical reasons significantly increases the risk of addiction and overdose.

What is a Blue Pill with an 'A 51' Imprint?

Accurately identifying prescription medication is a crucial safety measure. The pill in question, a small, round, blue tablet with the imprint 'A 51' on one side, is Oxycodone Hydrochloride 30 mg. It is manufactured by Actavis, a subsidiary of Teva Pharmaceuticals. This tablet is a potent opioid analgesic used for managing moderate to severe pain. Because it is a highly regulated controlled substance, it is critical to recognize and handle this medication with extreme care.

The Pharmacological Profile of Oxycodone

Oxycodone is an opioid medication that functions by binding to opioid receptors in the brain and nervous system. This action changes the way the body and brain feel and respond to pain, providing powerful analgesic effects. Its high potency means that even small doses can be effective, but also carry significant risks if misused or taken without proper medical supervision.

As a Schedule II controlled substance, Oxycodone poses a high risk of abuse and addiction, which can lead to overdose and death. Prescribers must assess a patient's risk of addiction before prescribing and monitor them carefully throughout treatment.

Medical Uses and Indications

Oxycodone Hydrochloride 30 mg is prescribed for pain management that is severe enough to require an opioid and for which alternative treatments are inadequate. It is typically used for short-term management of acute pain, such as after surgery or a serious injury, and sometimes for long-term chronic pain. Due to its immediate-release formulation, its pain-relieving effects begin relatively quickly.

Approved Medical Applications

Post-Surgical Pain: Helps manage the intense pain that often follows major surgical procedures.
Severe Injury Pain: Provides relief for severe pain caused by serious injuries or trauma.
Cancer-Related Pain: Used in palliative care to manage severe pain in patients with cancer.
Chronic Pain: In some cases, it may be prescribed for long-term management of chronic conditions, but only after other options have proven ineffective.

Serious Risks and Side Effects of Oxycodone

While effective for pain, Oxycodone carries a range of side effects, some of which are life-threatening. Patients should be aware of these potential dangers and report any concerning symptoms to their healthcare provider immediately.

Common vs. Severe Side Effects


Type	Common Side Effects	Severe Adverse Reactions
Neurological	Drowsiness, dizziness, headache, fatigue	Profound sedation, confusion, seizures
Gastrointestinal	Constipation, nausea, vomiting, stomach pain	Gastrointestinal obstruction, paralytic ileus
Cardiovascular	Slowed heartbeat, lightheadedness, hypotension	Circulatory depression, cardiac arrest
Respiratory	Unusual snoring, sleep apnea	Life-threatening respiratory depression, respiratory arrest
Other	Itching, sweating, decreased libido	Adrenal insufficiency, dependence, overdose, and death

The Dangers of Misuse and Addiction

Oxycodone is a powerful and highly addictive substance. Misuse can happen in various ways, including taking it in higher doses or more frequently than prescribed, or using it for non-medical purposes. This can lead to the rapid development of tolerance, physical dependence, and addiction. A dependence can trigger severe withdrawal symptoms if the drug is stopped abruptly, reinforcing the cycle of addiction.

Signs of Misuse and Addiction

Physical Dependence: Experiencing withdrawal symptoms (e.g., restlessness, muscle aches, anxiety) when not taking the drug.
Behavioral Changes: Taking higher doses than prescribed or using the drug for euphoric effects.
Psychological Dependence: Developing an intense craving for the drug.
Overdose Risk: Taking too much of the drug can lead to life-threatening respiratory depression, coma, and death.

How to Handle and Dispose of Oxycodone Safely

Due to the significant risks associated with this medication, it is crucial to handle it with the utmost care. Proper storage and disposal are essential to prevent accidental ingestion or diversion.

Safe Storage

Secure Location: Store the medication in a secure place, away from children, pets, and visitors.
Track Usage: Keep a record of the number of tablets to monitor for any missing doses.
Original Container: Keep the medication in its original, child-proof container.

Safe Disposal

Take-Back Programs: Use a medicine take-back program or a drug disposal site offered by your local pharmacy, hospital, or police department.
Flush When Necessary: If a take-back program is not readily available, the FDA and DEA advise flushing certain opioid medications, including Oxycodone, down the toilet to prevent accidental ingestion.
Consult Pharmacist: If you have questions about proper disposal, always ask a pharmacist for guidance.

Conclusion

The blue pill with a 51 on it is a powerful 30 mg Oxycodone tablet with substantial risks for abuse and addiction. It should only be used as prescribed for severe pain under a doctor's supervision. Given the dangers of misuse, it is paramount to understand the medication's effects, store it securely, and dispose of it properly. If you or someone you know is struggling with opioid addiction, seeking professional help is the most responsible course of action.

For more information on the risks of opioid analgesics, you can consult the FDA's official drug safety information.

Alternative Blue Pills

Different medications can appear visually similar. Here is a comparison of the 'A 51' oxycodone with other blue pills mentioned in search results:


Imprint	Active Ingredient	Strength	Appearance	Drug Class	Key Use
A 51	Oxycodone HCl	30 mg	Blue, round, scored	Opioid Analgesic	Moderate-to-severe pain
AS 10	Amphetamine Sulfate	10 mg	Blue, round	Stimulant	ADHD, narcolepsy
M SL 50	Sildenafil Citrate	50 mg	Blue, round	PDE5 inhibitor	Erectile dysfunction
ELI-511 10 mg	Amphetamine/Dextroamphetamine Extended Release	10 mg	Blue, capsule/oblong	Stimulant	ADHD, narcolepsy

It is important to remember that physical appearance alone is not enough to identify a pill, and cross-referencing with a pill identifier tool and your prescription information is essential. Always consult a healthcare professional with any questions.

Frequently Asked Questions

Oxycodone is an opioid analgesic used to manage pain severe enough to require an opioid, such as pain from injuries, surgery, or chronic conditions when other treatments have failed.

The 'A 51' pill is a high-dose opioid and can be dangerous if not used exactly as prescribed. It carries significant risks, including addiction, misuse, and life-threatening respiratory depression.

Common side effects include constipation, nausea, vomiting, dizziness, drowsiness, headache, and itching.

Store Oxycodone in a secure, locked location out of sight and reach of children, pets, and visitors. Keep track of the number of pills to ensure none are missing.

The safest way to dispose of Oxycodone is through a drug take-back program. If this is not an option, the FDA recommends flushing it down the toilet to prevent accidental harm.

If you find this pill and it is not your prescribed medication, do not take it. Safely dispose of it according to FDA guidelines or a take-back program. Do not keep it for potential future use, as it could be extremely dangerous for an individual who is not accustomed to such a high dose.

While the 'A 51' imprint is the legitimate mark for Oxycodone 30 mg, counterfeit pills are a widespread problem. Illicitly manufactured tablets, often made to look like real prescription drugs, can contain dangerous substances like fentanyl, and can be lethal. Always obtain medication from a licensed pharmacy.