The white round pill debossed with 05 52 (frequently featuring the boxed M logo) is an immediate-release oral prescription tablet containing Oxycodone Hydrochloride (5 mg), a potent semi-synthetic opioid analgesic used for the management of acute or severe pain.
Pill Identification
Attribute – Specification
- Active Ingredient – Oxycodone Hydrochloride, USP (5 mg)
- Imprint – 05 52 (or M on one side, 05 52 on the reverse/same side)
- Color & Shape – White, round tablet
- Size – Approximately 6 mm
- Manufacturer – Mallinckrodt Pharmaceuticals
- Drug Class – Opioid Agonist / Narcotic Analgesic
- Controlled Substance Schedule – DEA Schedule II (C-II)
Mechanism of Action
Oxycodone is a semi-synthetic pure opioid agonist derived from the opium alkaloid thebaine. Its therapeutic and central effects occur through the following neurochemical processes:
- Receptor Binding: Oxycodone primarily targets and selectively binds to opioid receptors distributed throughout the central nervous system (CNS), spinal cord, and peripheral tissues. It also exhibits weak affinity for kappa and delta opioid receptors.
- Intracellular Signaling: Activation of the G-protein-coupled opioid receptor inhibits adenylate cyclase activity, reduces intracellular cyclic adenosine monophosphate (cAMP), closes voltage-gated calcium channels presynaptically, and opens inwardly rectifying potassium channels postsynaptically.
- Inhibition of Pain Pathways: This hyperpolarizes neuronal membranes and diminishes the release of excitatory neurotransmitters (such as substance P, glutamate, and calcitonin gene-related peptide), inhibiting ascending nociceptive pain signaling to the brain while altering the emotional and subjective perception of pain.
Indications and Clinical Uses
- Moderate to Severe Acute Pain: Indicated for acute pain management (e.g., post-surgical trauma, severe injury) when alternative non-opioid analgesic options (such as NSAIDs or acetaminophen) are ineffective, poorly tolerated, or insufficient.
- Severe Chronic Pain: Utilized in select cases of persistent severe pain (such as advanced malignancy) when non-opioid or weaker therapies fail to achieve adequate analgesia.
Dosage and Administration
Prescribing guidelines mandate initiating therapy at the lowest effective dose for the shortest duration necessary.
- Opioid-Naïve Adult Starting Dose: Typically 5 mg to 15 mg orally every 4 to 6 hours as needed for pain.
- Administration: Swallow whole with water. Can be taken with or without food; taking with food or milk may help reduce mild gastrointestinal upset.
- Individualized Titration: Doses must be tailored based on patient response, pain severity, prior opioid exposure, and clinical tolerance.
- Hepatic / Renal Impairment: Clearance is significantly reduced in patients with impaired liver or kidney function; initial doses should be reduced (often by 50% to 75% of the standard starting dose) with extended dosing intervals and close clinical monitoring.
- Discontinuation: Patients who have received regular opioid therapy for more than a few days require a gradual dosage taper to avoid acute withdrawal symptoms.
Side Effects
Common Adverse Reactions:
- Gastrointestinal: Constipation (often requiring prophylactic stool softeners), nausea, vomiting, abdominal pain, dry mouth
- Central Nervous System: Drowsiness, sedation, dizziness, lightheadedness, headache
- Dermatologic: Pruritus (itching), flushing, diaphoresis (sweating)
Serious Adverse Reactions:
- Life-Threatening Respiratory Depression: Severe reduction in breathing rate and depth (hypoventilation, apnea)
- Profound CNS Depression: Coma, severe lethargy, unresponsiveness
- Cardiovascular Collapse: Severe hypotension, orthostatic syncope, bradycardia
- Serotonin Syndrome: When combined with serotonergic drugs (characterized by tremor, rigidity, hyperreflexia, hyperthermia, and confusion)
- Adrenal Insufficiency: Decreased cortisol production associated with prolonged opioid exposure
Drug Interactions
- Benzodiazepines and Other Sedatives: Concomitant use with benzodiazepines, barbiturates, general anesthetics, tranquilizers, or alcohol exponentially amplifies central nervous system and respiratory depression, frequently resulting in fatal overdose.
- CYP3A4 Inhibitors/Inducers: Oxycodone is primarily metabolized via cytochrome P450 3A4. Strong inhibitors (e.g., ketoconazole, clarithromycin, ritonavir) increase oxycodone plasma concentrations and overdose risk; inducers (e.g., rifampin, carbamazepine, St. John’s wort) decrease efficacy and can precipitate withdrawal.
- CYP2D6 Inhibitors: Strong CYP2D6 inhibitors (e.g., fluoxetine, paroxetine) alter the formation of the active metabolite oxymorphone, altering clinical response.
- MAO Inhibitors: Opioids should not be administered concomitantly with or within 14 days of monoamine oxidase inhibitors (MAOIs).
Boxed Warnings and Precautions
- Addiction, Abuse, and Misuse: Oxycodone carries a high risk of opioid use disorder, misuse, and diversion. Assess each patient’s risk prior to prescribing and monitor regularly for signs of aberrant drug-taking behaviors.
- Fatal Respiratory Depression: Serious, life-threatening, or fatal respiratory depression may occur even when taken as prescribed, with the highest risk during initiation or dosage increases.
- Accidental Ingestion: Accidental ingestion of even a single tablet – especially by children – can result in a fatal oxycodone overdose.
- Concomitant Use with Alcohol and CNS Depressants: Profound sedation, respiratory arrest, coma, and death may result from combined use.
- Neonatal Opioid Withdrawal Syndrome (NOWS): Prolonged use during pregnancy can lead to life-threatening withdrawal symptoms in the newborn requiring specialized neonatal management.
- Contraindications: Hypersensitivity to oxycodone, significant respiratory depression, acute or severe bronchial asthma in unmonitored settings, and known or suspected gastrointestinal obstruction, including paralytic ileus.