Fentanyl citrate injection

Table 2 includes clinically significant drug interactions with Fentanyl Citrate Injection. Table 2: Clinically Significant Drug Interactions with Fentanyl Citrate Injection Inhibitors of CYP3A4 Clinical Impact: The concomitant use of Fentanyl Citrate Injection and CYP3A4 inhibitors can increase the plasma concentration of fentanyl, resulting in increased or prolonged opioid effects, particularly when an inhibitor is added after a stable dose of Fentanyl Citrate Injection is achieved [see Warnings and Precautions (5.4) ] .

After stopping a CYP3A4 inhibitor, as the effects of the inhibitor decline, the fentanyl plasma concentration will decrease [see Clinical Pharmacology (12.3) ], resulting in decreased opioid efficacy or a withdrawal syndrome in patients who had developed physical dependence to fentanyl. Intervention: If concomitant use is necessary, consider dosage reduction of Fentanyl Citrate Injection until stable drug effects are achieved [see Dosage and Administration (2) ] . Monitor patients for respiratory depression and sedation at frequent intervals. If a CYP3A4 inhibitor is discontinued, consider increasing the Fentanyl Citrate Injection dosage until stable drug effects are achieved.

Monitor for signs of opioid withdrawal. Examples: Macrolide antibiotics (e.g., erythromycin), azole-antifungal agents (e.g., ketoconazole), protease inhibitors (e.g., ritonavir), grapefruit juice. CYP3A4 Inducers Clinical Impact: The concomitant use of Fentanyl Citrate Injection and CYP3A4 inducers can decrease the plasma concentration of fentanyl [see Clinical Pharmacology (12.3) ] , resulting in decreased efficacy or onset of a withdrawal syndrome in patients who have developed physical dependence to fentanyl [see Warnings and Precautions (5.4) ] .

After stopping a CYP3A4 inducer, as the effects of the inducer decline, the fentanyl plasma concentration will increase [see Clinical Pharmacology (12.3) ] , which could increase or prolong both the therapeutic effects and adverse reactions and may cause serious respiratory depression. Intervention: If concomitant use is necessary, consider increasing the Fentanyl Citrate Injection dosage until stable drug effects are achieved. Monitor for signs of opioid withdrawal. If a CYP3A4 inducer is discontinued, consider Fentanyl Citrate Injection dosage reduction and monitor for signs of respiratory depression.

Examples: Rifampin, carbamazepine, phenytoin Benzodiazepines and Other Central Nervous System (CNS) Depressants Clinical Impact: The concomitant use of Fentanyl Citrate Injection with CNS depressants may result in decreased pulmonary artery pressure and may cause hypotension. Even small dosages of diazepam may cause cardiovascular depression when added to high dose or anesthetic dosages of Fentanyl Citrate Injection. As postoperative analgesia, concomitant use of Fentanyl Citrate Injection can increase the risk of hypotension, respiratory depression, profound sedation, coma, and death.

Intervention: As postoperative analgesia, start with a lower dose of Fentanyl Citrate Injection and monitor patients for signs of respiratory depression, sedation, and hypotension. Fluids or other measures to counter hypotension should be available. [see Warnings and Precautions (5.3) ] . Examples: Benzodiazepines and other sedatives/hypnotics, anxiolytics, tranquilizers, muscle relaxants, general anesthetics, antipsychotics, gabapentinoids (gabapentin or pregabalin), other opioids, alcohol.

Serotonergic Drugs Clinical Impact: The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome [see Warnings and Precautions (5.8) ]. Intervention: If concomitant use is warranted, carefully observe the patient, particularly during treatment initiation and dose adjustment. Discontinue Fentanyl Citrate Injection if serotonin syndrome is suspected.

Examples: Selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants (TCAs), triptans, 5-HT3 receptor antagonists, drugs that effect the serotonin neurotransmitter system (e.g., mirtazapine, trazodone, tramadol), certain muscle relaxants (i.e., cyclobenzaprine, metaxalone), monoamine oxidase (MAO) inhibitors (those intended to treat psychiatric disorders and also others, such as linezolid and intravenous methylene blue).

Monoamine Oxidase Inhibitors Clinical Impact: MAOI interactions with opioids may manifest as serotonin syndrome [see Warnings and Precautions (5.8) ] or opioid toxicity (e.g., respiratory depression, coma) [see Warnings and Precautions (5.2) ] Intervention: The use of Fentanyl Citrate Injection is not recommended for patients taking MAOIs or within 14 days of stopping such treatment. Examples: Phenelzine, tranylcypromine, linezolid Mixed Agonist/Antagonist and Partial Agonist Opioid Analgesics Clinical Impact: May reduce the analgesic effect of Fentanyl Citrate Injection and/or precipitate withdrawal symptoms. Intervention: Avoid concomitant use.

Examples: Butorphanol, nalbuphine, pentazocine, buprenorphine. Muscle Relaxants Clinical Impact: Fentanyl may enhance the neuromuscular blocking action of skeletal muscle relaxants and produce an increased degree of respiratory depression. Intervention: Monitor patients for signs of respiratory depression that may be greater than otherwise expected and decrease the dosage of Fentanyl Citrate Injection and/or the muscle relaxant as necessary. Examples: Cyclobenzaprine, metaxalone. Diuretics Clinical Impact: Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.

Intervention: Monitor patients for signs of diminished diuresis and/or effects on blood pressure and increase the dosage of the diuretic as needed. Anticholinergic Drugs Clinical Impact: The concomitant use of anticholinergic drugs may increase risk of urinary retention and/or severe constipation, which may lead to paralytic ileus. Intervention: Monitor patients for signs of urinary retention or reduced gastric motility when Fentanyl Citrate Injection is used concomitantly with anticholinergic drugs.

Neuroleptics Clinical Impact: Elevated blood pressure, with and without pre-existing hypertension, has been reported following administration of Fentanyl Citrate Injection combined with a neuroleptic [see Warnings and Precautions (5.14) ] . Intervention: ECG monitoring is indicated when a neuroleptic agent is used in conjunction with Fentanyl Citrate Injection as an anesthetic premedication, for the induction of anesthesia, or as an adjunct in the maintenance of general or regional anesthesia. Nitrous oxide Clinical Impact: Nitrous oxide has been reported to produce cardiovascular depression when given with higher doses of Fentanyl Citrate Injection.

Intervention: Monitor patients for signs of cardiovascular depression that may be greater than otherwise expected. • Concomitant Use of CNS Depressants : May decrease pulmonary arterial pressure and may cause hypotension. See FPI for management instructions. For post-operative pain, start with the lowest effective dosage and monitor for potentiation of CNS depressant effects. ( 5.3 , 7 ) • Mixed Agonist/Antagonist and Partial Agonist Opioid Analgesics : Avoid use with Fentanyl Citrate Injection because they may reduce analgesic effect of Fentanyl Citrate Injection or precipitate withdrawal symptoms. ( 7 )

8.1 Pregnancy Risk Summary Use of opioid analgesics for an extended period of time during pregnancy may cause Neonatal Opioid Withdrawal Syndrome. Available data with Fentanyl Citrate Injection in pregnant women are insufficient to inform a drug‑associated risk for major birth defects and miscarriage ‎or adverse maternal outcomes‎. There are adverse outcomes reported with fetal exposure to opioid analgesics [see Clinical ‎Considerations ] .‎ In animal reproduction studies, fentanyl administration to pregnant rats during organogenesis was embryocidal at doses within the range of the human recommended dosing.

No evidence of malformations was noted in animal studies completed to date [see Data ]. The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. The background risk of major birth defects and miscarriage for the indicated population is unknown. All ‎pregnancies have a background risk of birth defect, loss, or other adverse outcomes.‎ In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2 to 4% and 15 to 20%, respectively.

Clinical Considerations 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. Labor or Delivery Opioids cross the placenta and may produce respiratory depression and psycho-physiologic effects in neonates. An opioid overdose reversal agent, such as naloxone or nalmefene, must be available for reversal of opioid-induced respiratory depression in the neonate. Fentanyl Citrate Injection is not recommended for use in pregnant women during or immediately prior to labor, when other analgesic techniques are more appropriate. Opioid analgesics, including Fentanyl Citrate Injection, can prolong labor through actions which temporarily reduce…