The T 194 pill is a prescription combination medication containing Oxycodone Hydrochloride (10 mg) and Acetaminophen (325 mg). It is classified as a Schedule II (C-II) controlled substance in the United States and is indicated for the management of acute pain severe enough to require an opioid analgesic when non-opioid options are inadequate or tolerated poorly.
Pill Identification & Physical Characteristics
Attribute – Specification
- Imprint –
T 194 - Active Ingredients – Oxycodone Hydrochloride 10 mg / Acetaminophen 325 mg
- Color – Yellow
- Shape – Round
- Scoring – Scored (bisected on one side)
- Drug Class – Opioid analgesic / Non-opioid analgesic combination
- DEA Schedule – Schedule II (C-II)
- Generic Equivalent To – Percocet 10/325, Endocet 10/325, Roxicet
Mechanism of Action
The combination provides multimodal pain relief via two distinct, complementary pathways:
- Oxycodone Hydrochloride: A semisynthetic opioid agonist selective primarily for the opioid receptors in the central nervous system (CNS) and spinal cord. Binding stimulates G-protein-coupled receptor pathways, closing voltage-gated calcium channels and opening inward-rectifying potassium channels. This inhibits presynaptic neurotransmitter release (e.g., glutamate, substance P), blunting ascending nociceptive signaling and altering the affective perception of pain.
- Acetaminophen (APAP): A centrally acting non-opioid analgesic and antipyretic. It produces analgesia primarily through central inhibition of cyclooxygenase (COX) enzymes, reduction of prostaglandin synthesis, and modulation of descending serotonergic pathways, effectively elevating the overall pain threshold without producing peripheral anti-inflammatory effects.
Dosage & Administration
- Standard Adult Dosage: Typically one tablet every 4 to 6 hours as needed for pain.
- Individualized Titration: Dosage must be adjusted based on the severity of pain, previous opioid exposure, patient response, and individual risk factors. Clinicians prescribe the lowest effective dosage for the shortest necessary duration.
- Acetaminophen Daily Maximums: To prevent acute hepatotoxicity, total daily acetaminophen consumption from all sources (prescription medications, OTC cough/cold products, sleep aids) must not exceed 4,000 mg in 24 hours (with many clinical protocols capping intake at 3,000 mg/day).
- Administration Rules: Tablets should be swallowed whole with water and can be taken with or without food; taking them with meals or milk can help mitigate nausea.
Side Effects
Common Side Effects
- Gastrointestinal: Nausea, vomiting, constipation, dry mouth, abdominal cramps.
- Central Nervous System: Drowsiness, dizziness, lightheadedness, sedation, headache.
- Dermatological: Pruritus (itching), flushing, hyperhidrosis (excessive sweating).
Severe & Adverse Reactions
- Respiratory Depression: Critically shallow, slow, or irregular breathing, which can lead to hypoxia, apnea, and cardiac arrest.
- Severe Hypotension & Bradycardia: Significant drops in blood pressure, orthostatic dizziness, and syncope.
- Hepatotoxicity: Acetaminophen-induced liver injury, presenting with jaundice, elevated transaminases, dark urine, or upper-right abdominal pain.
- Serious Skin Reactions: Rare, severe cutaneous adverse reactions (SCARs) linked to acetaminophen, including Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN).
- Adrenal Insufficiency: Chronic opioid therapy can suppress hypothalamic-pituitary-adrenal function, causing profound fatigue, weakness, and hypotension.
Precautions & Drug Interactions
- CNS Depressants: Co-administration with benzodiazepines, barbiturates, alcohol, sedating antihistamines, or muscle relaxants produces additive CNS and respiratory depression, vastly increasing the risk of profound sedation, coma, or fatal overdose.
- Hepatic CYP450 Interactions: Oxycodone is metabolized mainly by CYP3A4 (yielding noroxycodone) and CYP2D6 (yielding oxymorphone).
- CYP3A4 Inhibitors (e.g., ketoconazole, clarithromycin, ritonavir) can dramatically raise oxycodone plasma concentrations.
- CYP3A4 Inducers (e.g., rifampin, carbamazepine, St. John’s wort) can lower drug levels and precipitate withdrawal or inadequate analgesia.
- Serotonergic Agents: Concurrent use of oxycodone with SSRIs, SNRIs, tricyclic antidepressants, or MAO inhibitors carries a risk of life-threatening Serotonin Syndrome.
- Special Patient Populations: Extreme caution is required in patients with pre-existing respiratory disease (COPD, severe asthma, sleep apnea), severe hepatic or renal impairment, increased intracranial pressure, head trauma, or history of substance use disorder.
FDA Boxed Warnings
- Addiction, Abuse, and Misuse: Oxycodone exposes patients and other users to the risks of opioid addiction, abuse, and misuse, which can lead to overdose and death.
- Life-Threatening Respiratory Depression: Serious, life-threatening, or fatal respiratory depression may occur, particularly during initiation of therapy or following a dosage increase.
- Accidental Ingestion: Accidental ingestion of even one dose, especially by pediatric patients, can result in fatal respiratory depression.
- Neonatal Opioid Withdrawal Syndrome (NOWS): Prolonged maternal use during pregnancy can result in life-threatening withdrawal in neonates requiring specialized management.
- Hepatotoxicity (Acetaminophen): Acetaminophen has been associated with cases of acute liver failure, sometimes resulting in liver transplant and death, typically associated with exceeding daily maximum doses or combining with alcohol.
- Risks from Concomitant Use with Benzodiazepines or Other CNS Depressants: Concurrent use may result in profound sedation, respiratory depression, coma, and death.