Oxycodone and acetaminophen

Drug Interactions Inhibitors of CYP3A4 and CYP2D6 The concomitant use of oxycodone and acetaminophen tablets and CYP3A4 inhibitors, such as macrolide antibiotics (e.g., erythromycin), azole-antifungal agents (e.g. ketoconazole), and protease inhibitors (e.g., ritonavir), can increase the plasma concentration of oxycodone, resulting in increased or prolonged opioid effects. These effects could be more pronounced with concomitant use of oxycodone and acetaminophen tablets and CYP3A4 and CYP2D6 inhibitors, particularly when an inhibitor is added after a stable dose of oxycodone and acetaminophen tablets is achieved [see WARNINGS ].

After stopping a CYP3A4 inhibitor, as the effects of the inhibitor decline, the oxycodone plasma concentration will decrease [see CLINICAL PHARMACOLOGY ], resulting in decreased opioid efficacy or a withdrawal syndrome in patients who had developed physical dependence to oxycodone and acetaminophen tablets. If concomitant use is necessary, consider dosage reduction of oxycodone and acetaminophen tablets until stable drug effects are achieved. Evaluate patients at frequent intervals for respiratory depression and sedation. If a CYP3A4 inhibitor is discontinued, consider increasing the oxycodone and acetaminophen tablets dosage until stable drug effects are achieved.

Assess for signs of opioid withdrawal. Inducers of CYP3A4 The concomitant use of oxycodone and acetaminophen tablets and CYP3A4 inducers, such as rifampin, carbamazepine, and phenytoin, can decrease the plasma concentration of oxycodone [see CLINICAL PHARMACOLOGY ], resulting in decreased efficacy or onset of a withdrawal syndrome in patients who have developed physical dependence to oxycodone and acetaminophen tablets [see WARNINGS ].

After stopping a CYP3A4 inducer, as the effects of the inducer decline, the oxycodone plasma concentration will increase [see CLINICAL PHARMACOLOGY ], which could increase or prolong both the therapeutic effects and adverse reactions, and may cause serious respiratory depression. If concomitant use is necessary, consider increasing the oxycodone and acetaminophen tablets dosage until stable drug effects are achieved. Asess for signs of opioid withdrawal. If a CYP3A4 inducer is discontinued, consider oxycodone and acetaminophen tablets dosage reduction and evaluate patients at frequent intervals for signs of respiratory depression and sedation.

Benzodiazepines and Other CNS Depressants Due to additive pharmacologic effect, the concomitant use of benzodiazepines and other CNS depressants such as benzodiazepines and other sedative hypnotics, anxiolytics, tranquilizers, muscle relaxants, general anesthetics, antipsychotics, and other opioids, including alcohol, can increase the risk of hypotension, respiratory depression, profound sedation, coma, and death. Reserve concomitant prescribing of these drugs for use in patients for whom alternative treatment options are inadequate. Limit dosages and durations to the minimum required.

Inform patients and caregivers of this potential interaction and educate them on the signs and symptoms of respiratory depression (including sedation). If concomitant use is warranted, consider recommending or prescribing an opioid overdose reversal agent for the emergency treatment of opioid overdosee WARNINGS ; DOSAGE AND ADMINISTRATION ].

Examples: Benzodiazepines and other sedatives/hypnotics, anxiolytics, tranquilizers, muscle relaxants, general anesthetics, antipsychotics, gabapentinoids (gabapentin or pregabalin), other opioids, alcohol Serotonergic Drugs The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system, such as selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants (TCAs), tryptans, 5-HT3 receptor antagonists, drugs that affect the serotonin neurotransmitter system (e.g., mirtazapine, trazodone, tramadol), and monoamine oxidase (MAO) inhibitors (those intended to treat psychiatric disorders and also others, such as linezolid and intravenous methylene blue), has resulted in serotonin syndrome [see PRECAUTIONS; Information for Patients/Caregivers ]. If concomitant use is warranted, frequently evaluate the patient, particularly during treatment initiation and dose adjustment. Discontinue oxycodone and acetaminophen tablets if serotonin syndrome is suspected. Monoamine Oxidase Inhibitors (MAOIs) The concomitant use of opioids and MAOIs, such as phenelzine, tranylcypromine, linezolid, may manifest as serotonin syndrome or opioid toxicity (e.g., respiratory depression, coma) [see WARNINGS ]. The use of oxycodone and acetaminophen tablets is not recommended for patients taking MAOIs or within 14 days of stopping such treatment. If urgent use of an opioid is necessary, use test doses and frequent titration of small doses to treat pain while closely monitoring blood pressure and signs and symptoms of CNS and respiratory depression. Mixed Agonist/Antagonist and Partial Agonist Opioid Analgesics The concomitant use of opioids with other opioid analgesics, such as butorphanol, nalbuphine, pentazocine, may reduce the analgesic effect of oxycodone and acetaminophen tablets and/or precipitate withdrawal symptoms. Advise patient to avoid concomitant use of these drugs. Muscle Relaxants Oxycodone may enhance the neuromuscular-blocking action of skeletal muscle relaxants and produce an increase in the degree of respiratory depression. Because respiratory depression that may be greater than otherwise expected, decrease the dosage of oxycodone and acetaminophen tablets and/or the muscle relaxant as necessary. Due to the risk of respiratory depression with concomitant use of skeletal muscle relaxants and opioids, consider recommending or prescribing an opioid overdose reversal agent [ see WARNINGS ; DOSAGE AND ADMINISTRATION ]. Examples: Cyclobenzaprine, metaxalone. Diuretics Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Evaluate patients patients for signs of diminished diuresis and/or effects on blood pressure and increase the dosage of the diuretic as needed. Anticholinergic Drugs The concomitant use of anticholinergic drugs may increase risk of urinary retention and/or severe constipation, which may lead to paralytic ileus. Evaluate patients for signs of urinary retention or reduced gastric motility when oxycodone and acetaminophen tablets are used concomitantly with anticholinergic drugs. Alcohol, ethyl Hepatotoxicity has occurred in chronic alcoholics following various dose levels (moderate to excessive) of acetaminophen. Oral Contraceptives Increase in glucuronidation resulting in increased plasma clearance and a decreased half-life of acetaminophen. Charcoal (activated) Reduces acetaminophen absorption when administered as soon as possible after overdose. Beta Blockers (Propranolol) Propranolol appears to inhibit the enzyme systems responsible for the glucuronidation and oxidation of acetaminophen. Therefore, the pharmacologic effects of acetaminophen may be increased. Loop Diuretics The effects of the loop diuretic may be decreased because acetaminophen may decrease renal prostaglandin excretion and decrease plasma renin activity. Lamotrigine Serum lamotrigine concentrations may be reduced, producing a decrease in therapeutic effects. Probenecid Probenecid may increase the therapeutic effectiveness of acetaminophen slightly. Zidovudine The pharmacologic effects of zidovudine may be decreased because of enhanced non-hepatic or renal clearance of zidovudine.

Pregnancy Teratogenic Effects Pregnancy Category C Animal reproductive studies have not been conducted with oxycodone and acetaminophen tablets. It is also not known whether oxycodone and acetaminophen tablets can cause fetal harm when administered to a pregnant woman or can affect reproductive capacity. Oxycodone and acetaminophen tablets should not be given to a pregnant woman unless in the judgment of the physician, the potential benefits outweigh the possible hazards.

Nonteratogenic Effects Fetal/Neonatal Adverse Reactions Use of opioid analgesics for an extended period of time during pregnancy for medical or nonmedical purposes can result in physical dependence in the neonate and neonatal opioid withdrawal syndrome shortly after birth. Neonatal opioid withdrawal syndrome presents as irritability, hyperactivity and abnormal sleep pattern, high pitched cry, tremor, vomiting, diarrhea and failure to gain weight. The onset, duration, and severity of neonatal opioid withdrawal syndrome vary based on the specific opioid used, duration of use, timing and amount of last maternal use, and rate of elimination of the drug by the newborn.

Observe newborns for symptoms of neonatal opioid withdrawal syndrome and manage accordingly [see WARNINGS ].

Nursing Mothers Available data from lactation studies indicate that oxycodone is present in breastmilk and that doses of less than 60 mg/day of the immediate-release formulation are unlikely to result in clinically relevant exposures in breastfed infants. A pharmacokinetics study utilizing opportunistic sampling of 76 lactating women receiving oxycodone immediate-release products for postpartum pain management showed that oxycodone concentrates in breastmilk with an average milk to plasma ratio of 3.2. The relative infant dose was low, approximately 1.3% of a weight-adjusted maternal dose (see Data).

In the same study, among the 70 infants exposed to oxycodone in breastmilk, no adverse events were attributed to oxycodone. However, based on known adverse effects in adults, infants should be monitored for signs of excess sedation and respiratory depression [see Clinical Considerations]. There are no data on the effects of the oxycodone on milk production. Acetaminophen is also excreted in breast milk in low concentrations.

The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for oxycodone and acetaminophen tablets and any potential adverse effects on the breastfed infant from oxycodone and acetaminophen tablets or from the underlying maternal condition. Infants exposed to oxycodone and acetaminophen tablets through breast milk should be monitored for excess sedation and respiratory depression. Withdrawal symptoms can occur in breastfed infants when maternal administration of an opioid analgesic is stopped, or when breast-feeding is stopped.

Data Oxycodone concentration data from 76 lactating women receiving immediate-release oxycodone products for postpartum pain management, and 28 infants exposed to oxycodone in breastmilk showed that following a median (range) dose of oxycodone in mothers of 9.2 (5-10) mg/dose or 33.0 (5.4-59.3) mg/day, oxycodone concentrated in breastmilk with a median (range) milk to plasma ratio of 3.2 (1.2-5.3). However, when using maternal breastmilk data to estimate the daily and relative infant dose, the infant dose was 0.006 mg/kg/day, which is 1.3% of a weight-adjusted…