Amantadine hydrochloride, an adamantane derivative, is a synthetic antiviral agent that is active against influenza A virus.1, 2, 6
Treatment of Seasonal Influenza A Virus Infections
Amantadine has been used for the treatment of uncomplicated respiratory tract illness caused by various strains of influenza A viruses in adults, adolescents, and children 1 year of age or older.1, 2, 6 The drug is not a substitute for early vaccination as recommended by the Centers for Disease Control and Prevention (CDC) Advisory Committee on Immunization Practices (ACIP).1, 2, 6 While adamantanes (amantadine, rimantadine) were used more commonly in the past, these drugs are no longer recommended for antiviral treatment because of high levels of resistance among circulating influenza A viruses.137, 138
When amantadine has been used in otherwise healthy adults and children for symptomatic treatment of uncomplicated seasonal influenza caused by susceptible influenza A virus and administered within 24-48 hours after the onset of symptoms, the drug has decreased viral shedding and reduced the degree and duration of fever, headache, and respiratory symptoms with a more rapid return to routine daily activities and improvement in airway function.1, 2, 6, 19, 24, 26, 27, 41, 60, 74, 75 It is not known whether amantadine is effective for the symptomatic treatment of these infections when symptoms have been present for more than 48 hours since most controlled studies evaluating efficacy of the drug only included patients whose symptoms had been present for 48 hours or less.16, 34
There have been no well-controlled studies to date to determine the efficacy of amantadine treatment in preventing serious complications of influenza A virus infection (e.g., bacterial or viral pneumonia or exacerbation of chronic diseases).1, 2, 6, 26, 42 Most studies evaluating efficacy of amantadine for the treatment of influenza A infections have been performed in otherwise healthy adults and children with uncomplicated influenza; data are limited and inconclusive concerning efficacy of amantadine for treatment of influenza in individuals at high risk for serious influenza-related complications.26, 27
While amantadine and rimantadine generally are comparably effective in the treatment of influenza A infection caused by susceptible strains, some evidence suggests that symptomatic improvement during the initial 24 hours of therapy with usual dosages of amantadine may be somewhat faster than that with rimantadine, probably because of pharmacokinetic differences between the drugs.19, 27, 45, 59 In addition, although adverse effects of the drugs are similar, rimantadine may be associated with less frequent and/or severe nervous system effects.18, 24, 27, 29, 34, 44, 49, 51
Prior to the 2005-2006 influenza season, most influenza A (H3N2) strains circulating in the US were susceptible to adamantanes (amantadine, rimantadine).105, 116, 121 However, seasonal influenza A (H3N2) and influenza A (H1N1)pdm09 viruses circulating during recent influenza seasons have been resistant to these drugs.105, 112, 117, 129, 144, 162, 551, 552 In addition, the influenza A (H1N1)pdm09 virus, previously referred to as the novel 2009 influenza A (H1N1) virus or swine-origin influenza A (H1N1) virus, that has circulated during more recent influenza seasons is resistant to amantadine and rimantadine.52, 105, 112, 117, 144, 151, 162, 551, 552 Amantadine and rimantadine have little or no activity against influenza B.1, 2, 6, 24, 26, 27, 45, 551
Current guidelines from CDC and other experts recommend the use of neuraminidase inhibitors (e.g., oseltamivir, zanamivir, peramavir) when antiviral treatment is needed in patients with suspected or confirmed influenza.137, 138 Adamantanes (amantadine, rimantadine) are not recommended for antiviral treatment because of high levels of resistance among circulating influenza A viruses.137, 138 Viral surveillance data available from local and state health departments and the CDC should be considered when selecting an antiviral for treatment of seasonal influenza.112, 137, 144 Strains of circulating influenza viruses and the antiviral susceptibility of these strains constantly evolve.137, 144 The CDC issues recommendations concerning the use of antiviral agents for the treatment of influenza, and these recommendations are updated as needed during each influenza season.137, 144 Information regarding influenza surveillance and updated recommendations for treatment of seasonal influenza are available from CDC at [Web]
Prevention of Seasonal Influenza A Virus Infections
Amantadine has been used for prophylaxis against influenza infection caused by susceptible influenza A viruses in adults, adolescents, and children 1 year of age or older.1, 2, 6 The drug is not a substitute for early vaccination as recommended by CDC.1, 2, 6 Adamantanes (amantadine, rimantadine) are currently not recommended by CDC and other experts for antiviral chemoprophylaxis because of high levels of resistance among circulating influenza A viruses.137, 144
Results of numerous studies indicate that amantadine is about 60-90% effective in preventing influenza caused by susceptible strains of influenza A.27, 34, 71, 72 Clinical studies indicate that amantadine is as effective as rimantadine24, 27, 34 or influenza vaccination24 in preventing influenza A illness. The protective effect of amantadine or rimantadine and influenza vaccination may be additive.42, 44, 73 In contrast to results of studies evaluating efficacy when antiviral prophylaxis is given for a season or part of a season, results of studies evaluating antiviral prophylaxis with amantadine or rimantadine after a known exposure have not been consistent.22, 24, 45, 46 While postexposure prophylaxis with amantadine or rimantadine provided protection in families when the index case did not receive antiviral therapy, the drugs did not provide protection from influenza A infection in household contacts when amantadine or rimantadine was used to treat the index case, presumably because of spread of resistant virus within the household.22, 24, 42, 44, 45, 46
Annual vaccination with seasonal influenza virus vaccine, as recommended by the US Public Health Service Advisory Committee on Immunization Practices (ACIP), is the primary means of preventing seasonal influenza and its severe complications.1, 2, 6, 105, 112, 116, 144, 488 Prophylaxis with an appropriate antiviral agent active against circulating influenza strains is considered an adjunct to vaccination for the control and prevention of influenza in certain individuals.1, 2, 6, 105, 112, 116, 144, 488
The Infectious Diseases Society of America (IDSA) states that antiviral drugs should not be used for routine or widespread chemoprophylaxis outside of institutional outbreaks, but may be considered in certain situations (e.g., patients at high risk of developing complications from influenza).138 If antiviral chemoprophylaxis is needed, neuraminidase inhibitors are recommended; adamantanes (amantadine, rimantadine) should not be used for chemoprophylaxis because of high levels of resistance among circulating influenza A viruses.137, 138 Viral surveillance data available from local and state health departments and the CDC should be considered when selecting an antiviral for the prophylaxis of influenza.112, 137, 488 The most appropriate antiviral for prevention of influenza is selected based on information regarding the likelihood of the influenza strain being susceptible and the known adverse effects of the drug.137, 144 Strains of circulating influenza viruses and the antiviral susceptibility of these strains constantly evolve.137, 144 The CDC issues recommendations concerning the use of antiviral agents for prophylaxis of influenza, and these recommendations are updated as needed during each influenza season.137, 144 Information regarding influenza surveillance and updated recommendations for prevention of seasonal influenza are available from CDC at at [Web]
Amantadine hydrochloride is administered orally.1, 2, 6 Adverse effects (e.g., CNS effects) may be minimized if the daily dosage is given in 2 equally divided doses.1, 2, 6
Amantadine hydrochloride is commercially available as tablets or liquid-filled capsules containing 100 mg of the drug and as an oral solution containing 50 mg/5 mL.1, 2, 6
Treatment of Seasonal Influenza A Virus Infections
For the treatment of uncomplicated respiratory tract illness caused by susceptible influenza A viruses, the usual adult dosage of amantadine hydrochloride is 200 mg daily.1, 2, 6 The dosage can be given as a single daily dose or as 100 mg twice daily.1, 2, 6 The drug should be initiated as soon as possible, preferably within 24-48 hours after the onset of symptoms, and continued for 24-48 hours after symptoms disappear.1, 2 6
Prevention of Seasonal Influenza A Virus Infections
For prophylaxis of influenza caused by susceptible influenza A viruses, the usual adult dosage of amantadine hydrochloride is 200 mg daily.1, 2, 6 The dosage can be given as a single daily dose or as 100 mg twice daily.1, 2, 6
Some clinicians suggest that a dosage of 100 mg daily can be used as an alternative regimen for the prophylaxis of influenza A infection.1, 2, 6, 17 Although limited evidence suggests that a 100-mg daily dosage may be effective for prophylaxis in healthy adults who are not at risk for influenza-related complications and is associated with fewer adverse effects, the relative efficacy of 100- versus 200-mg daily dosages for prophylaxis of influenza virus A infection has not been determined.1, 2, 6, 17 The manufacturer states that the 100-mg daily dosage is recommended for individuals who have CNS or other toxicities while receiving the 200-mg daily dosage.1, 2, 6
Amantadine prophylaxis should be continued for at least 10 days following a known exposure.1, 2, 6 If used as an adjunct to influenza vaccination, the drug usually is administered for 2-4 weeks after the vaccine is given to provide prophylaxis until a protective antibody response develops.1, 2, 6
Treatment or Prevention of Seasonal Influenza A Virus Infections
The dosage of amantadine hydrochloride recommended by the manufacturers for the treatment or prophylaxis of uncomplicated influenza caused by susceptible influenza A viruses in children 9-12 years of age is 100 mg twice daily.1, 2, 6 The American Academy of Pediatrics (AAP) states that children 10 years of age or older should receive a dosage of 100 mg twice daily if they weigh 40 kg or more or a dosage of 5 mg/kg daily given in 2 divided doses if they weigh less than 40 kg.105 While the manufacturers state that a dosage of 100 mg once daily has not been evaluated in children and there are no data demonstrating whether this dosage is as effective or safer than the 200 mg daily dosage in this age group,1, 2, 6 AAP suggests that a dosage of 100 mg daily is an acceptable alternative dosage for prophylaxis of influenza A illness in children who weigh more than 20 kg.105
For children 1-9 years of age, the manufacturer recommends that amantadine hydrochloride be given in a dosage of 4.4-8.8 mg/kg daily (up to 150 mg daily) for the treatment or prophylaxis of influenza caused by susceptible influenza A.1, 2, 6 AAP recommends that children 1-9 years of age receive 5 mg/kg (up to 150 mg) daily given in 2 divided doses.105
Initiate as soon as possible for treatment, preferably within 24-48 hours after onset of symptoms, and continue for 24-48 hours after symptoms disappear.1, 2, 6
Amantadine prophylaxis should be continued for at least 10 days following a known exposure.1, 2, 6 If used as an adjunct to influenza vaccination, the drug usually is administered for 2-4 weeks after the vaccine is given to provide prophylaxis until a protective antibody response develops.1, 2, 6
Manufacturers make no specific dosage adjustment recommendations for patients with hepatic impairment.1, 2, 6
When amantadine hydrochloride is used in patients with renal impairment, a reduced dosage is recommended.1, 2, 6
The manufacturers recommend that patients with creatinine clearance of 30-50 mL/minute per 1.73 m2 receive 200 mg of amantadine hydrochloride on the first day, followed by 100 mg once daily thereafter and those with creatinine clearance of 15-29 mL/minute per 1.73 m2 receive 200 mg on the first day, followed by 100 mg on alternate days thereafter.1, 2, 6 The manufacturers recommend that patients with creatinine clearance less than 15 mL/minute per 1.73 m2 and hemodialysis patients receive a dosage of 200 mg every 7 days.1, 2, 6
Because dosage adjustment based on creatinine clearance may provide only an approximation of the optimal dosage of amantadine hydrochloride for a given patient, such patients should be observed carefully so that adverse reactions can be recognized promptly and either the dose can be reduced further or the drug can be discontinued as necessary.144 Hemodialysis contributes minimally to clearance of amantadine.1, 2, 6, 144
The usual dosage of amantadine hydrochloride for the treatment or prophylaxis of influenza infection caused by susceptible influenza A viruses in adults 65 years of age or older without recognized renal disease is 100 mg daily.1, 2, 6
Since renal function normally declines with age and amantadine-induced adverse effects have been reported more frequently in geriatric patients, some clinicians state that 100 mg daily should be the maximum dosage of amantadine hydrochloride for adults 65 years of age or older, and that dosage may need to be further reduced in some geriatric patients.1, 2, 6
Deaths from overdosage of amantadine have occurred; the lowest reported acute lethal dose was 1 g.1, 2, 6 Acute toxicity may be attributed to the anticholinergic effects of the drug.1, 2, 6 Overdosage also has been reported in patients with renal impairment who were prescribed higher than recommended doses of amantadine for their level of renal function.1, 2, 6
Suicide attempts (resulting in death in some patients) and suicidal ideation have been reported in patients receiving amantadine, many of whom received short courses of the drug for influenza prophylaxis or treatment.1, 2, 6
Patients receiving amantadine should be monitored for depression, including suicidal ideation and behavior.1, 2, 6 Clinicians should weigh the risks versus benefits of treatment in patients with a history of suicidality or depression.1, 2, 6
Hallucinations and Psychotic Behavior
Hallucinations and other psychiatric symptoms or behaviors (e.g., confusion, psychosis, personality changes, agitation, aggressive behavior, paranoia) have been reported with amantadine.1, 2, 6 Patients should be monitored for these effects, particularly after initiation of therapy and when dosage is increased or decreased.1, 2, 6 Use of amantadine is generally not advised in patients with major psychotic disorders because of the risk of exacerbating psychosis.1, 2, 6
Patients with active seizure disorders appear to be at risk of an increased frequency of seizures during amantadine therapy.1, 2, 6 Seizures also have been reported in patients with renal impairment and in geriatric individuals.1, 2, 6 Patients with a history of seizures should be observed closely for possible increased seizure activity.1, 2, 6
Because of possible CNS effects or visual disturbances, patients receiving amantadine should be warned that the drug may impair their ability to perform hazardous activities requiring mental alertness or physical coordination such as operating machinery or driving a motor vehicle.1, 2, 6 Patients should avoid excessive alcohol use since it may increase the potential for CNS effects.1, 2, 6
Dizziness and Orthostatic Hypotension
Dizziness and orthostatic hypotension have been reported in patients receiving amantadine.1, 2 6
Patients receiving amantadine should be monitored for signs and symptoms of orthostatic hypotension, particularly after initiation of therapy and when dosage is increased.1, 2, 6
Neuroleptic Malignant Syndrome
A symptom complex resembling possible neuroleptic malignant syndrome (NMS; characterized by fever, muscular rigidity, altered consciousness, autonomic instability) has been reported in patients receiving drugs that increase central dopaminergic tone; such reactions have been associated with rapid dosage reduction or withdrawal of the drug.1, 2, 6 Observe patients carefully when dosage of amantadine is reduced abruptly or discontinued.1, 2, 6
Impulse Control and Compulsive Behaviors
Intense urges and compulsive behaviors (e.g., urge to gamble, increased sexual urges, binge eating, uncontrolled spending, other intense urges) and the inability to control these urges have been reported in patients receiving drugs that increase central dopaminergic tone, including amantadine.1, 2, 6 These urges stopped in some cases when dosage was reduced or the drug was discontinued.1, 2, 6
If a patient develops intense urges and compulsive behaviors (e.g., urge to gamble, increased sexual urges, binge eating, uncontrolled spending, other intense urges) while receiving amantadine, consider reducing the dosage or discontinuing therapy.1, 2, 6 In addition, because patients may not recognize such behaviors as abnormal, clinicians should specifically ask patients or caregivers whether any new or increased urges or behaviors have developed during treatment with amantadine.1, 2, 6
Data from epidemiologic studies indicate that patients with parkinson disease have an approximately 2- to 6-fold greater risk of developing melanoma than the general population. It is unclear whether this increased risk is due to the disease or other factors (e.g., drugs used to treat the disease).1, 2, 6 Because of these findings, some manufacturers recommend that patients and clinicians monitor for melanoma on a frequent and regular basis during amantadine therapy.1, 2, 6 Periodic skin examinations should ideally be performed by qualified clinicians (e.g., dermatologists).1, 2, 6
Amantadine has been reported to be embryotoxic/teratogenic in rats when administered in dosages of 50 and 100 mg/kg daily (1.5 and 3 times, respectively, the maximum recommended human dosage on a mg/m2 basis), but not when administered in a dosage of 37 mg/kg daily (the maximum recommended human dosage on a mg/m2 basis).1, 2, 6 One woman with a movement disorder similar to parkinsonian syndrome who may have been treated with amantadine hydrochloride (100 mg daily) during the first trimester of pregnancy delivered a child with a complex cardiovascular lesion (single ventricle and pulmonary atresia) that may have been caused by the drug.89, 96 Fallot and tibial hemimelia (normal karyotype) were reported in an infant exposed to oral amantadine hydrochloride during the first trimester of pregnancy (100 mg daily for 7 days during week 6 and 7 of gestation).1, 2, 6 There are no adequate and well-controlled studies using amantadine in pregnant women, and the drug should be used during pregnancy only when the potential benefits outweigh the possible risks to the fetus.1, 2, 6
Because amantadine is distributed into human milk, some manufacturers state that the drug should not be used in nursing women.1, 2, 6
Safety and efficacy of amantadine for the prevention or treatment of infections caused by influenza A viruses have not been established in neonates or children younger than 1 year of age.1, 2, 6
Geriatric adults may have decreased renal function and because individuals with renal impairment may be at increased risk of amantadine-induced toxicity, the dosage of amantadine hydrochloride for adults in this age group should not exceed 100 mg daily.1, 2, 6 This dosage may need to be reduced further in some geriatric patients.1, 2, 6
Care should be exercised when administering amantadine to patients with liver disease.1, 2, 6 Rare cases of reversible elevation of liver enzymes have been reported in patients receiving the drug.1, 2, 6
Because amantadine is mainly excreted in the urine, drug accumulation may occur in patients with renal impairment.1, 2, 6 The half-life of amantadine is prolonged at least 2- to 3-fold in patients with impaired renal function (i.e., creatinine clearance less than 40 mL/minute per 1.73 m2).1, 2, 6 Reduced dosages of amantadine are recommended in patients with renal impairment.1, 2, 6
The most common adverse effects (5-10%) of amantadine include nausea, dizziness, and insomnia.1, 2, 6
Drugs with Anticholinergic Activity
Administration of amantadine in patients receiving drugs with anticholinergic activity may result in increased adverse anticholinergic and CNS effects.1, 2, 6, 90, 91, 92, 93 When amantadine is administered to patients already near the limit of tolerance for anticholinergic agents, atropinism with nocturnal confusion and hallucinations may gradually develop.92 It has been suggested that the dosage of the anticholinergic agent be reduced prior to the initiation of amantadine therapy or that the dose of either drug be reduced if atropine-like adverse effects appear.90, 91, 92, 93
Since the excretion rate of amantadine increases rapidly when the urine is acidic, administration of urine acidifying drugs may increase the elimination of the drug.1, 2, 6 Alterations of urine pH towards the alkaline condition may lead to drug accumulation, possibly increasing adverse reactions.1, 2, 6 Monitor for efficacy or adverse reactions of amantadine in situations where urine pH may be altered to a more acidic or alkaline state, respectively.1, 2, 6
Concomitant use of alcohol and amantadine is not recommended because of the potential for increased risk of CNS effects.1, 2, 6
To avoid the possibility of additive CNS stimulant effects, amantadine should be administered with caution to patients receiving other CNS stimulant drugs.1, 2, 6
Toxic delirium has occurred following initiation of co-trimoxazole in at least one patient who had been stabilized on amantadine; rapid resolution occurred following discontinuance of the drugs.98
Triamterene and Hydrochlorothiazide
Concomitant use of amantadine hydrochloride (100 mg 3 times daily) and a fixed-combination preparation containing triamterene and hydrochlorothiazide in a 61-year-old man with parkinsonian syndrome resulted in increased plasma concentrations of amantadine; however, it is not known which component of the combination preparation may have been responsible for the interaction or whether related drugs would produce a similar effect.1, 2, 6, 90, 126
Amantadine hydrochloride does not interfere with the antibody response to influenza virus vaccine inactivated (IIV) and the vaccine may be administered concomitantly with or at any time before or after amantadine.1, 2, 6, 100
Safety and efficacy of concomitant use of influenza vaccine live intranasal (LAIV) and amantadine have not been studied.100 Because influenza antiviral agents reduce replication of influenza viruses and may inhibit the vaccine virus, LAIV should not be administered until at least 48 hours after amantadine is discontinued and amantadine should not be administered until at least 2 weeks after administration of LAIV, unless medically indicated.100 If amantadine is administered within 2 weeks after LAIV, the US Public Health Service Advisory Committee on Immunization Practices (ACIP) recommends that the LAIV dose be repeated 48 hours or more after the last dose of the antiviral agent.100 Alternatively, individuals who received amantadine 2 days before to 14 days after LAIV may be revaccinated with either IIV or influenza vaccine recombinant (RIV).100
Concomitant use of quinidine or quinine with amantadine reduces renal clearance of amantadine by about 30%.1, 2, 6, 97
Amantadine is an adamantane derivative (a symmetric tricyclic amine) that is structurally related to rimantadine.1, 2, 6, 22, 26, 27, 29, 44, 45, 49 The exact mechanism of antiviral activity of amantadine has not been fully elucidated.1, 2, 6, 24, 26, 27, 45, 46, 47, 48 Amantadine inhibits viral replication by interfering with the influenza A virus M2 protein, an integral membrane protein.1, 2, 6, 24, 26, 27, 45, 46, 47, 48 The M2 protein of influenza A functions as an ion channel and is important in at least 2 aspects of virus replication, disassembly of the infecting virus particle and regulation of the ionic environment of the transport pathway.26, 27, 45, 46, 47 By interfering with the ion channel function of the M2 protein, amantadine inhibits 2 stages in the replicative cycle of influenza A.24, 26, 27, 45, 46, 47 Early in the virus replicative cycle, amantadine inhibits uncoating of the virus particle, presumably by inhibiting the acid-mediated dissociation of the virion nucleic acid and proteins, which prevents nuclear transport of viral genome material.1, 2, 6, 24, 26, 27, 43, 45, 46, 99 Amantadine also prevents viral maturation in some strains of influenza A (e.g., H7 strains) by promoting pH-induced conformational changes in influenza A hemagglutinin during its intracellular transport late in the replicative cycle.1, 2, 6, 26, 27, 43, 45, 46, 47, 99 Adsorption of the virus to and penetration into cells do not appear to be affected by amantadine.43, 45, 47, 48 In addition, amantadine does not interfere with the synthesis of viral components (e.g., RNA-directed RNA polymerase activity).43, 48
Beginning in the 2005-2006 influenza season, most influenza A (H3N2) strains circulating in the US were resistant to amantadine and rimantadine.121 Resistance to amantadine and rimantadine among seasonal influenza A (H3N2) circulating during recent influenza seasons has remained high.105, 112, 117, 144, 162, 551, 552
Amantadine treatment of established influenza A infection does not appear to interfere with antibody response to the infection; however, some reduction in local immune responses has been observed in some patients.27, 44, 45 Because prophylactic use of amantadine can prevent influenza illness and to a lesser extent subclinical infection, some individuals who take amantadine can still develop immune responses that may protect them when they are exposed to the same or antigenically related viruses following discontinuance of amantadine prophylaxis.99, 127
Amantadine hydrochloride is well absorbed from the GI tract.1, 2, 6, 12, 27, 45, 56, 63, 67 While peak plasma concentrations are directly related to amantadine hydrochloride dosage up to 200 mg daily, higher dosages may result in a greater than proportional increase in peak plasma concentration.1, 2, 6, 67 While amantadine principally is excreted unchanged in urine by glomerular filtration and tubular secretion, at least 8 metabolites have been identified in urine.1, 2, 6, 19, 48, 67 The elimination half-life of amantadine has been variously reported as 9-37 hours, with an average of 24 hours or less.1, 2, 6, 48, 56, 63, 65, 67, 68 Amantadine is only minimally removed by hemodialysis.1, 2, 6
Additional Information
The American Society of Health-System Pharmacists, Inc. represents that the information provided in the accompanying monograph was formulated with a reasonable standard of care, and in conformity with professional standards in the field. Readers are advised that decisions regarding use of drugs are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and that the information contained in the monograph is provided for informational purposes only. The manufacturer's labeling should be consulted for more detailed information. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information contained in the monograph is not a substitute for medical care.
Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.
Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.
Routes | Dosage Forms | Strengths | Brand Names | Manufacturer |
|---|---|---|---|---|
Oral | Capsules | 100 mg* | Amantadine Hydrochloride Capsules | |
Solution | 50 mg/5 mL* | Amantadine Hydrochloride Solution | ||
Tablets | 100 mg* | Amantadine Hydrochloride Tablets |
* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name
AHFS® Drug Information. © Copyright, 1959-2025, Selected Revisions September 10, 2024. American Society of Health-System Pharmacists, Inc., 4500 East-West Highway, Suite 900, Bethesda, MD 20814.
Only references cited for selected revisions after 1984 are available electronically.
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