Meperidine Hydrochloride

Boxed Warnings 08/2025 Indications and Usage ( 1 ) 10/2025 Dosage and Administration ( 2.2 , 2.6 ) 10/2025 Warnings and Precautions ( 5.2 , 5.3 , 5.4 , 5.15 , 5.16, 5.17) 10/2025

1 INDICATIONS AND USAGE Meperidine hydrochloride tablets are indicated for the management of acute pain severe enough to require an opioid analgesic and for which alternative treatments are inadequate. Limitations of Use Because of the risks of addiction, abuse, misuse, overdose, and death, which can occur at any dosage or duration and persist over the course of therapy [see Warnings and Precautions (5.2) ], reserve opioid analgesics, including meperidine hydrochloride tablets for use in patients for whom alternative treatment options are ineffective, not tolerated, or would be otherwise inadequate to provide sufficient management of pain. Meperidine hydrochloride tablets should not be used for treatment of chronic pain. Use of meperidine hydrochloride tablets for an extended period of time may increase the risk of toxicity (e.g., seizures) from the accumulation of the meperidine metabolite, normeperidine. Meperidine hydrochloride tablets are opioid agonists indicated for the management of pain, severe enough to require an opioid analgesic and for which alternative treatments are inadequate. ( 1 ) Limitations of Use: Because of the risks of addiction, abuse, misuse, overdose, and death, which can occur at any dosage or duration and persist over the course of therapy, reserve opioid analgesics, including meperidine hydrochloride tablets, for use in patients for whom alternative treatment options are ineffective, not tolerated, or would be otherwise inadequate to provide sufficient management of pain. ( 1 , 5.2 ) Meperidine hydrochloride tablets should not be used for the treatment of chronic pain. Use of meperidine hydrochloride tablets for an extended period of time may increase the risk of toxicity (e.g., seizures) from the accumulation of the meperidine metabolite, normeperidine.

2 DOSAGE AND ADMINISTRATION • Meperidine hydrochloride tablets should be prescribed only by healthcare professionals who are knowledgeable about the use of opioids and how to mitigate the associated risks. ( 2.1 ) • Use the lowest effective dosage for the shortest duration of time consistent with individual patient treatment goals. Reserve titration to higher doses of Meperidine hydrochloride tablets for patients in whom lower doses are insufficiently effective and in whom the expected benefits of using a higher dose opioid clearly outweigh the substantial risks. ( 2.1 , 5) • Many acute pain conditions (e.g., the pain that occurs with a number of surgical procedures or acute musculoskeletal injuries) require no more than a few days of an opioid analgesic. Clinical guidelines on opioid prescribing for some acute pain conditions are available. ( 2.1 ) • Initiate the dosing regimen for each patient individually, taking into account the patient’s underlying cause and severity of pain, prior analgesic treatment and response, and risk factors for addiction, abuse, and misuse. ( 2.1 , 5.3 ) • Respiratory depression can occur at any time during opioid therapy, especially when initiating and following dosage increases with Meperidine hydrochloride tablets. Consider this risk when selecting an initial dose and when making dose adjustments. ( 2.1 , 5.4 ) • Discuss opioid overdose reversal agents and options for acquiring them with the patient and/or caregiver, both when initiating and renewing treatment with meperidine hydrochloride tablets, especially if the patient has additional risk factors for overdose, or close contacts at risk for exposure and overdose. ( 2.2, 5.2 , 5.3 , 5.4 ) • Adult Patients : Initiate treatment in adults with 50 mg to 150 mg orally, every 3 to 4 hours as needed for pain, at the lowest dose necessary to achieve adequate analgesia ( 2.4 ). Titrate the dose based upon the individual patient’s response to their initial dose of Meperidine hydrochloride tablets. • Pediatric Patients : Initiate treatment in pediatric patients with 1.1 mg/kg to 1.8 mg/kg orally, up to the adult dose, every 3 to 4 hours as needed, at the lowest dose necessary to achieve adequate analgesia ( 2.4 ). Titrate the dose based upon the individual patient’s response to their initial dose of Meperidine hydrochloride tablets. • Periodically reassess patients receiving meperidine hydrochloride tablets to evaluate the continued need for opioid analgesics to maintain pain control, for the signs or symptoms of adverse reactions, and for the development of addiction, abuse, or misuse. ( 2.5 ) • Do not rapidly reduce or abruptly discontinue meperidine hydrochloride tablets in a physically dependent patient because rapid reduction or abrupt discontinuation of opioid analgesics has resulted in serious withdrawal symptoms, uncontrolled pain, and suicide. ( 2.6 ) 2.1 Important Dosage and Administration Instructions Meperidine hydrochloride tablets should be prescribed only by healthcare professionals who are knowledgeable about the use of opioids and how to mitigate the associated risks. Use the lowest effective dosage for the shortest duration of time consistent with individual patient treatment goals [see Warnings and Precautions (5) ]. Because the risk of overdose increases as opioid doses increase, reserve titration to higher doses of meperidine hydrochloride tablets for patients in whom lower doses are insufficiently effective and in whom the expected benefits of using a higher dose opioid clearly outweigh the substantial risks. Many acute pain conditions (e.g., the pain that occurs with a number of surgical procedures or acute musculoskeletal injuries) require no more than a few days of an opioid analgesic. Clinical guidelines on opioid prescribing for some acute pain conditions are available. There is variability in the opioid analgesic dose and duration needed to adequately manage pain due both to the cause of pain and to individual patient factor …

3 DOSAGE FORMS AND STRENGTHS • 50 mg tablet (white, round biconvex tablets, debossed “Є” above bisect and “50” below bisect on one side, plain on the other side) • 100 mg tablet (white, round biconvex tablets, debossed “Є51” on one side and bisected on the other side) Tablets: 50 mg and 100 mg. ( 3 )

4 CONTRAINDICATIONS Meperidine hydrochloride tablets are contraindicated in patients with: • Significant respiratory depression [see Warnings and Precautions (5.3) ] • Acute or severe bronchial asthma in an unmonitored setting or in the absence of resuscitative equipment [see Warnings and Precautions (5.11) ] • Concomitant use of monoamine oxidase inhibitors (MAOIs) or within 14 days of having taken an MAOI [see Drug Interactions (7) ] • Known or suspected gastrointestinal obstruction, including paralytic ileus [see Warnings and Precautions (5.15) ] • Hypersensitivity to meperidine or to any of other ingredients of the product (e.g., anaphylaxis) [see Adverse Reactions (6) ] • Significant respiratory depression. ( 4 ) • Acute or severe bronchial asthma in an unmonitored setting or in absence of resuscitative equipment. ( 4 ) • Concomitant use of monoamine oxidase inhibitors (MAOIs) or within 14 days of having taken an MAOI. ( 4 ) • Known or suspected gastrointestinal obstruction, including paralytic ileus. ( 4 ) • Hypersensitivity to meperidine or to any other ingredients of the product. ( 4 )

6 ADVERSE REACTIONS The following serious adverse reactions are described, or described in greater detail, in other sections: • Addiction, Abuse, and Misuse [see Warnings and Precautions (5.2) ] • Life-Threatening Respiratory Depression [see Warnings and Precautions (5.3) ] • Interactions with Benzodiazepines or Other CNS Depressants [see Warnings and Precautions (5.4) ] • Neonatal Opioid Withdrawal Syndrome [see Warnings and Precautions (5.5) ] • Opioid-Induced Hyperalgesia and Allodynia [see Warnings and Precautions (5.9) ] • Serotonin Syndrome [see Warnings and Precautions (5.10) ] • Adrenal Insufficiency [see Warnings and Precautions (5.12) ] • Severe Hypotension [see Warnings and Precautions (5.13) ] • Gastrointestinal Adverse Reactions [see Warnings and Precautions (5.15) ] • Seizures [see Warnings and Precautions (5.16) ] • Withdrawal [see Warnings and Precautions (5.17) ] The following adverse reactions associated with the use of meperidine were identified in clinical studies or postmarketing reports. Because some of these reactions were reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. The major hazards of meperidine, as with other opioid analgesics, are respiratory depression and, to a lesser degree, circulatory depression, respiratory arrest, shock, and cardiac arrest. The most frequently observed adverse reactions included lightheadedness, dizziness, sedation, nausea, vomiting, and sweating. These effects seem to be more prominent in ambulatory patients and in those who are not experiencing severe pain. In such individuals, lower doses are advisable. Some adverse reactions in ambulatory patients may be alleviated if the patient lies down. Other adverse reactions include: Nervous System: Mood changes (e.g., euphoria, dysphoria), weakness, headache, agitation, tremor, involuntary muscle movements (e.g., muscle twitches, myoclonus), severe convulsions, seizures, transient hallucinations and disorientation, confusion, delirium, visual disturbances. Gastrointestinal: Dry mouth, constipation, biliary tract spasm. Cardiovascular: Flushing of the face, tachycardia, bradycardia, palpitation, hypotension [see Warnings and Precautions (5.7) ], syncope. Genitourinary: Urinary retention. Allergic: Pruritus, urticaria, other skin rashes, wheal and flare over the vein with intravenous injection. Hypersensitivity reactions, anaphylaxis. Histamine release leading to hypotension and/or tachycardia, flushing, sweating, and pruritus. Serotonin syndrome: Cases of serotonin syndrome, a potentially life-threatening condition, have been reported during concomitant use of opioids with serotonergic drugs. Adrenal insufficiency: Cases of adrenal insufficiency have been reported with opioid use, more often following greater than one month of use. Androgen deficiency : Cases of androgen deficiency have occurred with use of opioids for an extended period of time [see Clinical Pharmacology (12.2) ]. Hyperalgesia and Allodynia : cases of hyperalgesia and allodynia have been reported with opioid therapy of any duration [see Warnings and Precautions (5.9) ]. Hypoglycemia: Cases of hypoglycemia have been reported in patients taking opioids. Most reports were in patients with at least one predisposing risk factor (e.g., diabetes). Opioid-induced esophageal dysfunction (OIED ): Cases of OIED have been reported in patients taking opioids and may occur more frequently in patients taking higher doses of opioids, and/or in patients taking opioids longer term [see Warnings and Precautions (5.15) ] . Adverse Reactions from Observational Studies A prospective, observational cohort study estimated the risks of addiction, abuse, and misuse in patients initiating long-term use of Schedule II opioid analgesics between 2017 and 2021. Study participants included in one or more analyses had been enrolled in selected insurance plans or health s …

7 DRUG INTERACTIONS Table 1 includes clinically significant drug interactions with meperidine hydrochloride tablets. Table 1: Clinically Significant Drug Interactions with Meperidine Hydrochloride Tablets Monoamine Oxidase Inhibitors (MAOIs) Clinical Impact: Meperidine is contraindicated in patients who are receiving monoamine oxidase (MAOIs) or those who have recently received such agents. Therapeutic doses of meperidine have occasionally precipitated unpredictable, severe, and occasionally fatal reactions in patients who have received such agents within 14 days. The mechanism of these reactions is unclear, but may be related to a preexisting hyperphenylalaninemia. Some have been characterized by coma, severe respiratory depression, cyanosis, and hypotension, and have resembled the syndrome of acute narcotic overdose. Serotonin syndrome with agitation, hyperthermia, diarrhea, tachycardia, sweating, tremors and impaired consciousness may also occur. In other reactions the predominant manifestations have been hyperexcitability, convulsions, tachycardia, hyperpyrexia, and hypertension. Intervention: Do not use meperidine hydrochloride tablets in patients taking MAOIs or within 14 days of stopping such treatment. Intravenous hydrocortisone or prednisolone have been used to treat severe reactions, with the addition of intravenous chlorpromazine in those cases exhibiting hypertension and hyperpyrexia. The usefulness and safety of narcotic antagonists in the treatment of these reactions is unknown.) Examples: phenelzine, tranylcypromine, linezolid Inhibitors of CYP3A4 and CYP2B6 Clinical Impact: The concomitant use of meperidine hydrochloride tablets and CYP3A4 or CYP2B6 inhibitors can increase the plasma concentration of meperidine, resulting in increased or prolonged opioid effects. These effects could be more pronounced with concomitant use of meperidine hydrochloride tablets and CYP2B6 and CYP3A4 inhibitors, particularly when an inhibitor is added after a stable dose of meperidine hydrochloride tablets is achieved [see Warnings and Precautions (5.7) ] . After stopping a CYP3A4 or CYP2B6 inhibitor, as the effects of the inhibitor decline, the meperidine 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 meperidine. Intervention: If concomitant use is necessary, consider dosage reduction of meperidine hydrochloride tablets until stable drug effects are achieved. Evaluate patients at frequent intervals for respiratory depression and sedation. If a CYP3A4 or CYP2B6 inhibitor is discontinued, consider increasing the meperidine hydrochloride tablets dosage until stable drug effects are achieved. Assess for signs of opioid withdrawal. Examples: Macrolide antibiotics (e.g., erythromycin), azole-antifungal agents (e.g., ketoconazole), protease inhibitors (e.g., ritonavir) CYP3A4 and CYP2B6 Inducers Clinical Impact: The concomitant use of meperidine hydrochloride tablets and CYP3A4 or CYP2B6 inducers can decrease the plasma concentration of meperidine [see Clinical Pharmacology (12.3) ] , resulting in decreased efficacy or onset of a withdrawal syndrome in patients who have developed physical dependence to meperidine [see Warnings and Precautions (5.7) ] . After stopping a CYP3A4 or CYP2B6 inducer, as the effects of the inducer decline, the meperidine 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 meperidine hydrochloride tablets dosage until stable drug effects are achieved. Assess for signs of opioid withdrawal. If a CYP3A4 or CYP2B6 inducer is discontinued, consider meperidine hydrochloride tablets dosage reduction and evaluate patients at frequent intervals for signs of respi …

8 USE IN SPECIFIC POPULATIONS Pregnancy : May cause fetal harm ( 8.1 ). 8.1 Pregnancy Risk Summary Use of opioid analgesics for an extended period of time during pregnancy may cause neonatal opioid withdrawal syndrome [see Warnings and Precautions (5.5) ] . Available data with meperidine hydrochloride tablets are insufficient to inform a drug-associated risk for major birth defects and miscarriage or adverse maternal outcomes. Formal animal reproduction studies have not been conducted with meperidine. Neural tube defects (exencephaly and cranioschisis) have been reported in hamsters administered a single bolus dose of meperidine during a critical period of organogenesis at 0.85 and 1.5 times the total human daily dose of 1200 mg [see Data ]. 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 [see Warnings and Precautions (5.5) ] . Labor or Delivery Opioids cross the placenta and may produce respiratory depression and psycho-physiologic effects in neonates. Resuscitation may be required [see Overdosage (10) ]. An opioid overdose reversal agent, such as naloxone or nalmefene, must be available for reversal of opioid-induced respiratory depression in the neonate. Meperidine hydrochloride tablets are not recommended for use in pregnant women during or immediately prior to labor, when other analgesic techniques are more appropriate. Opioid analgesics, including meperidine hydrochloride tablets, can prolong labor through actions which temporarily reduce the strength, duration, and frequency of uterine contractions. However, this effect is not consistent and may be offset by an increased rate of cervical dilation, which tends to shorten labor. Monitor neonates exposed to opioid analgesics during labor for signs of excess sedation and respiratory depression. Data Animal Data Formal reproductive and developmental toxicology studies for meperidine have not been completed. In a published study, neural tube defects (exencephaly and cranioschisis) were noted following subcutaneous administration of meperidine hydrochloride (127 and 218 mg/kg, respectively) on Gestation Day 8 to pregnant hamsters (0.85 and 1.5 times the total daily dose of 1200 mg/day based on body surface area). The findings cannot be clearly attributed to maternal toxicity. 8.2 Lactation Risk Summary Meperidine appears in the milk of nursing mothers receiving the drug. The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for meperidine hydrochloride tablets and any potential adverse effects on the breastfed infant from meperidine hydrochloride tablets or from the underlying maternal condition. Clinical Considerations Monitor infants exposed to meperidine hydrochloride tablets through breast milk for excess sedation and respiratory depression. Withdrawal symptoms can occur in breastfed infants when maternal administration of an opioid analgesic is sto …

12.1 Mechanism of Action Meperidine is an opioid agonist with multiple actions qualitatively similar to those of morphine; the most prominent of these involve the central nervous system and organs composed of smooth muscle. The principal actions of therapeutic value are analgesia and sedation.

11 DESCRIPTION Meperidine hydrochloride tablets are opioid agonists. Meperidine hydrochloride tablets are available as 50 mg for oral administration. The chemical name is 4-Piperidinecarboxylic acid, 1-methyl-4-phenyl-,ethyl ester, hydrochloride. The molecular weight is 283.80. Its molecular formula is C 15 H 21 NO 2 ∙HCl, and it has the following chemical structure. Meperidine hydrochloride is a white crystalline substance with a melting point of 186°C to 189°C. It is readily soluble in water and has a neutral reaction and a slightly bitter taste. The solution is not decomposed by a short period of boiling. The tablets contain 50 mg of meperidine hydrochloride. The Inactive Ingredients in meperidine hydrochloride tablets include: hypromellose, microcrystalline cellulose, colloidal silicon dioxide, sodium starch glycolate, and stearic acid. Meperidine hydrochloride tablets 50 mg, are white, round, scored, and convex debossed with "214" on one side and "G" bisect "L"on the other side. Chemical Structure

10 OVERDOSAGE Clinical Presentation Acute overdose with meperidine hydrochloride tablets can be manifested by respiratory depression, somnolence progressing to stupor or coma, skeletal muscle flaccidity, cold and clammy skin, constricted pupils, and, in some cases, pulmonary edema, bradycardia, hypotension, hypoglycemia, partial or complete airway obstruction, atypical snoring, and death. Marked mydriasis rather than miosis may be seen with hypoxia in overdose situations [see Clinical Pharmacology (12.2) ]. Toxic leukoencephalopathy has been reported after opioid overdose and can present hours, days, or weeks after apparent recovery from the initial intoxication. Accumulation of normeperidine as in chronic use or possibly following introduction of a concomitant CYP3A4 inducer presents as excitatory syndrome including hallucinations, tremors, muscle twitches, dilated pupils, hyperactive reflexes, and convulsions. Treatment of Overdose In case of overdose, priorities are the reestablishment of a patent and protected airway and institution of assisted or controlled ventilation, if needed. Employ other supportive measures (including oxygen and vasopressors) in the management of circulatory shock and pulmonary edema as indicated. Cardiac arrest or arrhythmias will require advanced life-support measures. For clinically significant respiratory or circulatory depression secondary to meperidine overdose, administer an opioid overdose reversal agent such as naloxone or nalmefene. Because the duration of opioid reversal is expected to be less than the duration of action of meperidine in meperidine hydrochloride tablets, carefully monitor the patient until spontaneous respiration is reliably reestablished. If the response to an opioid overdose reversal agent is suboptimal or only brief in nature, administer additional reversal agent as directed by the product’s prescribing information. In an individual physically dependent on opioids, administration of the recommended dosage of the opioid overdose reversal agent will precipitate an acute withdrawal syndrome. The severity the withdrawal symptoms experienced will depend on the degree of physical dependence and the dose of reversal agent administered. If a decision is made to treat serious respiratory depression in the physically-dependent patient, administration of the reversal agent should begin with care and by titration with smaller than usual doses of the reversal agent.

16 HOW SUPPLIED/STORAGE AND HANDLING Meperidine Hydrochloride Tablets USP, 50 mg are white, round biconvex tablets, debossed “Є” above bisect and “50” below bisect on one side, plain on the other side, available in bottles of 30, NDC 42806-050-30 and in bottles of 100, NDC 42806-050-01. Meperidine Hydrochloride Tablets USP, 100 mg are white, round biconvex tablets, debossed “Є51” on one side and bisected on the other side, available in bottles of 100, NDC 42806-051-01. Dispense in a tight, light-resistant container as defined in the USP, with a child-resistant closure (as required). Store at 20° to 25° C (68° to 77° F) [See USP Controlled Room Temperature]. Store meperidine hydrochloride tablets securely and dispose of properly [see Patient Counseling Information (17) ].