Amantadine Hydrochloride 100 mg Tablet, 100-count
Other active recalls for Amantadine Hydrochloride (different manufacturers) — 1 · tap to view
🆔 Identity & classification
Where does this data come from?
🏷️ RxNorm drug class
This medicine belongs to the Influenza A M2 Protein Inhibitor class.
Where does this data come from?
🏭 Manufacturer & labeler
Where does this data come from?
🩺 Clinical
- Amantadine only works against influenza A — it won't help with influenza B, COVID-19, colds, or stomach bugs. And it works best for the flu when you start it early in the illness....
- Can I take amantadine to treat a regular flu or a stomach bug?
- The ones that matter most are hallucinations (seeing or hearing things that aren't there), significant dizziness — especially when you stand up — and any vision changes like sudden...
- I take amantadine for Parkinson's — what side effects should I actually watch for?
Patient education
Supplement & herbal interactions
Where does this data come from?
Ask a licensed pharmacist directly — free, answered by our team.
🧪 Inactive Ingredients / Excipients
Inactive ingredients, also called excipients, are components of the drug product other than the active ingredient. They may include fillers, dyes, coatings, preservatives, flavors, or other formulation ingredients.
💡 Tap an ingredient (hover on desktop) to see what it is and why it’s used.
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UNII LMI26O6933
Alumina is a white powder form of aluminum oxide. It's used as a filler to add bulk to tablets and capsules, and sometimes as a thickening or anti-caking agent in powdered formulations.
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UNII H77VEI93A8
A synthetic yellow dye used to color medications. It helps identify the drug and make it visually distinctive, with no effect on how the medicine works.
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UNII 70097M6I30
Magnesium stearate is a salt made from magnesium and stearic acid, a fatty substance. It's used in tablets and capsules as a lubricant and glidant to help ingredients flow smoothly during manufacturing and prevent sticking.
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UNII OP1R32D61U
Microcrystalline cellulose is a purified form of cellulose, a natural fiber from plant sources. It acts as a binder and filler in tablets and capsules, helping hold ingredients together and give the medicine its shape and size.
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UNII FZ989GH94E
Povidone is a synthetic polymer made from a plastic-like material. It acts as a binder to hold tablet ingredients together and as a disintegrant to help the tablet break apart in your stomach so the medicine can be absorbed.
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UNII ETJ7Z6XBU4
Silicon dioxide is a naturally occurring mineral used as a glidant and anti-caking agent. It helps powder ingredients flow smoothly and prevents clumping during manufacturing and storage.
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UNII 8I089SAH3T
A carbohydrate powder extracted from potatoes. It serves as a filler to add bulk and volume to the tablet or capsule, and as a disintegrant to help the medicine break apart and release its active ingredient in your body.
7 inactive ingredients listed in the exact product block matched to this NDC.
Where does this data come from?
ingredient classCode="IACT" elements from the exact product block matched by this NDC. Label-section narrative from DailyMed / the openFDA label index is shown separately when available.Inactive ingredient FAQ
Are inactive ingredients the same for every manufacturer?
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💲 Pricing
A drug doesn't have one price. Each row is a different public payment system, and none is what you'd pay at the counter — that depends on your insurance. The ⓘ on each row explains what it measures.
| Price system | Per ea | Per package |
|---|---|---|
| Retail pharmacies payNADAC · weekly | $0.312 | $31.15 / 100 tablet |
| Medicaid paysCMS SDUD · 12 mo | No recent Medicaid claims on file for this NDC — rare and low-volume NDCs are suppressed in the public data. | |
| Medicare drug plans payPart D · Q2 2026 | $0.5201 | $52.01 / 100 tablet |
Where does this data come from?
🔁 Therapeutic equivalents
| Product | Labeler | Pack | NADAC/unit | TE | Status | Price vs. this |
|---|---|---|---|---|---|---|
| Amantadine Hydrochloride 100 mgthis 00832-0111-03 | Upsher-Smith | 100 tablets | $0.311 | AB | Discontinued | — |
| Amantadine Hydrochloride 100 mg 42543-0497-01 | Strides | 100 tablets | $0.311 | AB | Availability likely | — |
| Amantadine 100 mg 62332-0586-31 | Alembic | 100 tablets | $0.311 | AB | Availability likely | — |
| Amantadine Hydrochloride 100 mg 00591-4920-01 | Actavis | 100 tablets | $0.315 | — | Discontinued | +1% |
| Amantadine 100 mg 00615-8605-39 | NCS | 30 tablets | — | AB | FDA listed | — |
| Amantadine Hydrochloride 100 mg 10135-0692-01 | Marlex | 100 tablets | — | AB | FDA listed | — |
| Amantadine 100 mg 46708-0586-31 | Alembic | 100 tablets | — | AB | FDA listed | — |
| Amantadine Hydrochloride 100 mg 67046-1452-03 | Coupler | 30 tablets | — | AB | FDA listed | — |
| Amantadine 100 mg 67046-1531-03 | Coupler | 30 tablets | — | AB | FDA listed | — |
| Amantadine Hydrochloride 100 mg 71765-0009-01 | Zhejiang | 24 tablets | — | AB | FDA listed | — |
| Amantadine HCL 100 mg 72189-0535-30 | Direct_Rx | 30 tablets | — | AB | FDA listed | — |
| Amantadine 100 mg 82804-0267-20 | Proficient | 20 tablets | — | AB | FDA listed | — |
Where does this data come from?
⏳ Availability & generic status
This product is an FDA-approved generic. Other versions of the same drug are listed under Therapeutic equivalents, least expensive first.
Where does this data come from?
💊 Medicaid utilization by pack size
🔬 Reported adverse events (FAERS)
Top reported reactions
Age at onset
Reporter sex
Serious outcomes
Where does this data come from?
📦 Packaging — all sizes for this product
| Package NDC | Description | Per unit | Per pack | Marketing start | Status |
|---|---|---|---|---|---|
| 00832-0111-00 | 100 TABLET in 1 BOTTLE (0832-0111-00) | $0.3115 / ea | $31.15 | 2011-12-15 | Active |
| 00832-0111-03 You're viewing this | 100 BLISTER PACK in 1 CARTON (0832-0111-03) / 1 TABLET in 1 BLISTER PACK (0832-0111-89) | $0.3115 / ea | $31.15 | 2017-07-07 | Discontinued by firm |
| 00832-0111-50 | 500 TABLET in 1 BOTTLE (0832-0111-50) | $0.3115 / ea | $155.74 | 2011-12-15 | Active |
This pack effectively ties for the lowest per-ea cost of the 3 priced pack sizes ($0.3115 NADAC).
This pack shows little to no recent Medicaid volume — the 100 tablets pack carries most fills. See all packs ↓
Pack size FAQ
What quantity is in NDC 00832-0111-03?
What is the difference between NDC 00832-0111-03 and NDC 00832-0111-00?
What NDC number is used to bill for this package of Amantadine Hydrochloride 100 mg Tablet?
Prices are the latest CMS NADAC pharmacy acquisition cost per NDC; per-pack figures are per-unit × pack quantity, shown only when the pack is denominated in the same measure NADAC prices.
🧭 About this NDC listing & data coverage
What data is (and isn’t) available for this NDC — tap to expand
| NDC identity (package / product / labeler codes) | ✓ Available |
| Labeler | ✓ Available |
| Product & package description | ✓ Available |
| Marketing category & status | ✓ Available |
| Active ingredient / dosage form / route | ✓ Available |
| FDA label (SPL via DailyMed) | ✓ Available |
| Package photos | — Not published for this NDC No photo available yet for this listing. |
| Inactive ingredients (structured) | ✓ Available |
| NADAC pharmacy acquisition price (CMS) | ✓ Available |
| Orange Book / therapeutic-equivalence data | ✓ Available |
| HCPCS J-code billing crosswalk | — Not published for this NDC Most self-administered / retail products have no J-code — that is normal. |
| Medicaid utilization (CMS SDUD) | — Not published for this NDC CMS reports utilization only for NDCs with Medicaid claims above its privacy threshold. |
Questions about this listing
What does the discontinued status mean for this NDC?
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Does this product come in other package sizes?
Who lists this product with the FDA?
Do I need a prescription for this product?
Where does this data come from?
📄 Full prescribing information FDA SPL
🎯 Indications and Usage ▾
INDICATIONS AND USAGE Amantadine hydrochloride tablets are indicated for the prophylaxis and treatment of signs and symptoms of infection caused by various strains of influenza A virus. Amantadine hydrochloride tablets are also indicated in the treatment of parkinsonism and drug-induced extrapyramidal reactions. Influenza A Prophylaxis Amantadine hydrochloride tablets are indicated for chemoprophylaxis against signs and symptoms of influenza A virus infection.
Because amantadine hydrochloride tablets do not completely prevent the host immune response to influenza A infection, individuals who take this drug may still develop immune responses to natural disease or vaccination and may be protected when later exposed to antigenically related viruses. Following vaccination during an influenza A outbreak, amantadine hydrochloride tablets prophylaxis should be considered for the 2 to 4 week time period required to develop an antibody response. Influenza A Treatment Amantadine hydrochloride tablets are also indicated in the treatment of uncomplicated respiratory tract illness caused by influenza A virus strains especially when administered early in the course of illness.
There are no well-controlled clinical studies demonstrating that treatment with amantadine hydrochloride tablets will avoid the development of influenza A virus pneumonitis or other complications in high-risk patients. There is no clinical evidence indicating that amantadine hydrochloride tablets are effective in the prophylaxis or treatment of viral respiratory tract illnesses other than those caused by influenza A virus strains. The following points should be considered before initiating treatment or prophylaxis with amantadine hydrochloride tablets: Amantadine hydrochloride tablets are not a substitute for early vaccination on an annual basis as recommended by the Centers for Disease Control and Prevention Advisory Committee on Immunization Practices.
Influenza viruses change over time. Emergence of resistance mutations could decrease drug effectiveness. Other factors (for example, changes in viral virulence) might also diminish clinical benefit of antiviral drugs.
Prescribers should consider available information on influenza drug susceptibility patterns and treatment effects when deciding whether to use amantadine hydrochloride tablets. Parkinson's Disease / Syndrome Amantadine hydrochloride tablets are indicated in the treatment of idiopathic Parkinson's disease (Paralysis Agitans), postencephalitic parkinsonism, and symptomatic parkinsonism which may follow injury to the nervous system by carbon monoxide intoxication. It is indicated in those elderly patients believed to develop parkinsonism in association with cerebral arteriosclerosis.
In the treatment of Parkinson's disease, amantadine hydrochloride tablets are less effective than levodopa, (-)-3-(3,4-dihydroxyphenyl)-L-alanine, and its efficacy in comparison with the anticholinergic antiparkinson drugs has not yet been established. Drug-Induced Extrapyramidal Reactions Amantadine hydrochloride tablets are indicated in the treatment of drug-induced extrapyramidal reactions. Although anticholinergic-type side effects have been noted with amantadine hydrochloride tablets when used in patients with drug-induced extrapyramidal reactions, there is a lower incidence of these side effects than that observed with the anticholinergic antiparkinson drugs.
⏱️ Dosage and Administration ▾
DOSAGE AND ADMINISTRATION The dose of amantadine hydrochloride tablets may need reduction in patients with congestive heart failure, peripheral edema, orthostatic hypotension, or impaired renal function (see Dosage for Impaired Renal Function ) . Dosage for Prophylaxis and Treatment of Uncomplicated Influenza A Virus Illness Adult The adult daily dosage of amantadine hydrochloride tablets is 200 mg; two 100 mg tablets as a single daily dose. The daily dosage may be split into one tablet of 100 mg twice a day.
If central nervous system effects develop in once-a-day dosage, a split dosage schedule may reduce such complaints. In persons 65 years of age or older, the daily dosage of amantadine hydrochloride tablets is 100 mg. A 100 mg daily dose has also been shown in experimental challenge studies to be effective as prophylaxis in healthy adults who are not at high risk for influenza-related complications.
However, it has not been demonstrated that a 100 mg daily dose is as effective as a 200 mg daily dose for prophylaxis, nor has the 100 mg daily dose been studied in the treatment of acute influenza illness. In recent clinical trials, the incidence of central nervous system (CNS) side effects associated with the 100 mg daily dose was at or near the level of placebo. The 100 mg dose is recommended for persons who have demonstrated intolerance to 200 mg of amantadine hydrochloride tablets daily because of CNS or other toxicities.
Pediatric Patients 1 yr. to 9 yrs. of age The total daily dose should be calculated on the basis of 2 to 4 mg/lb/day (4.4 to 8.8 mg/kg/day), but not to exceed 150 mg per day. 9 yrs. to 12 yrs. of age The total daily dose is 200 mg given as one tablet of 100 mg twice a day. The 100 mg daily dose has not been studied in this pediatric population.
Therefore, there are no data which demonstrate that this dose is as effective as or is safer than the 200 mg daily dose in this patient population. Prophylactic dosing should be started in anticipation of an influenza A outbreak and before or after contact with individuals with influenza A virus respiratory tract illness. Amantadine hydrochloride tablets should be continued daily for at least 10 days following a known exposure.
If amantadine hydrochloride tablets are used chemoprophylactically in conjunction with inactivated influenza A virus vaccine until protective antibody responses develop, then it should be administered for 2 to 4 weeks after the vaccine has been given. When inactivated influenza A virus vaccine is unavailable or contraindicated, amantadine hydrochloride tablets should be administered for the duration of known influenza A in the community because of repeated and unknown exposure. Treatment of influenza A virus illness should be started as soon as possible, preferably within 24 to 48 hours after onset of signs and symptoms and should be continued for 24 to 48 hours after the disappearance of signs and symptoms.
Dosage for Parkinsonism Adult The usual dose of amantadine hydrochloride tablets is 100 mg twice a day when used alone. Amantadine hydrochloride tablets have an onset of action usually within 48 hours. The initial dose of amantadine hydrochloride tablets is 100 mg daily for patients with serious associated medical illnesses or who are receiving high doses of other antiparkinson drugs.
After one to several weeks at 100 mg once daily, the dose may be increased to 100 mg twice daily, if necessary. Occasionally, patients whose responses are not optimal with amantadine hydrochloride tablets at 200 mg daily may benefit from an increase up to 400 mg daily in divided doses. However, such patients should be supervised closely by their physicians.
Patients initially deriving benefit from amantadine hydrochloride tablets not uncommonly experience a fall-off of effectiveness after a few months. Benefit may be regained by increasing the dose to 300 mg daily. Alternatively, temporary discontinuation of amantadine hydrochloride tablets for several week…
⛔ Contraindications ▾
CONTRAINDICATIONS Amantadine hydrochloride tablets are contraindicated in patients with known hypersensitivity to amantadine hydrochloride or to any of the other ingredients in amantadine hydrochloride tablets.
⚠️ Warnings ▾
WARNINGS Deaths Deaths have been reported from overdose with amantadine hydrochloride. The lowest reported acute lethal dose was 1 gram. Acute toxicity may be attributable to the anticholinergic effects of amantadine.
Drug overdose has resulted in cardiac, respiratory, renal or central nervous system toxicity. Cardiac dysfunction includes arrhythmia, tachycardia and hypertension (see OVERDOSAGE ). Deaths due to drug accumulation (overdosage) have been reported in patients with renal impairment, who were prescribed higher than recommended doses of amantadine hydrochloride for their level of renal function (see DOSAGE AND ADMINISTRATION: Dosage for Impaired Renal Function and OVERDOSAGE ) .
Suicide Attempts Suicide attempts, some of which have been fatal, have been reported in patients treated with amantadine hydrochloride, many of whom received short courses for influenza treatment or prophylaxis. The incidence of suicide attempts is not known, and the pathophysiologic mechanism is not understood. Suicide attempts and suicidal ideation have been reported in patients with and without prior history of psychiatric illness.
Amantadine hydrochloride can exacerbate mental problems in patients with a history of psychiatric disorders or substance abuse. Patients who attempt suicide may exhibit abnormal mental states which include disorientation, confusion, depression, personality changes, agitation, aggressive behavior, hallucinations, paranoia, other psychotic reactions, and somnolence or insomnia. Because of the possibility of serious adverse effects, caution should be observed when prescribing amantadine hydrochloride tablets to patients being treated with drugs having CNS effects, or for whom the potential risks outweigh the benefit of treatment.
CNS Effects Patients with a history of epilepsy or other "seizures" should be observed closely for possible increased seizure activity. Patients receiving amantadine hydrochloride tablets who note central nervous system effects or blurring of vision should be cautioned against driving or working in situations where alertness and adequate motor coordination are important. Other Patients with a history of congestive heart failure or peripheral edema should be followed closely as there are patients who developed congestive heart failure while receiving amantadine hydrochloride tablets.
Patients with Parkinson's disease improving on amantadine hydrochloride tablets should resume normal activities gradually and cautiously, consistent with other medical considerations, such as the presence of osteoporosis or phlebothrombosis. Because amantadine hydrochloride tablets have anticholinergic effects and may cause mydriasis, it should not be given to patients with untreated angle closure glaucoma. Corneal Edema Corneal edema has been reported in patients taking amantadine.
Symptoms include sudden onset of blurry vision, or progressive vision loss, with or without eye pain. Corneal involvement is usually bilateral. Onset can occur from a few weeks to several years after starting amantadine.
Resolution of symptoms typically begins within weeks after amantadine cessation. However, corneal grafts have been required in some patients when the conditionis not recognized. Permanent damage can occur if amantadine continued.
Ask patients if their vision has changed and obtain ophthalmologic examination to rule out corneal edema should vision changes occur after initiation of therapy with amantadine. If corneal edema occurs, taper and discontinue amantadine [see Dosage and Administration ] .
🤒 Adverse Reactions ▾
ADVERSE REACTIONS The adverse reactions reported most frequently at the recommended dose of amantadine hydrochloride (5% to 10%) are: nausea, dizziness (lightheadedness), and insomnia. Less frequently (1% to 5%) reported adverse reactions are: depression, anxiety and irritability, hallucinations, confusion, anorexia, dry mouth, constipation, ataxia, livedo reticularis, peripheral edema, orthostatic hypotension, headache, somnolence, nervousness, dream abnormality, agitation, dry nose, diarrhea, and fatigue. Infrequently (0.1% to 1%) occurring adverse reactions are: congestive heart failure, psychosis, urinary retention, dyspnea, skin rash, vomiting, weakness, slurred speech, euphoria, thinking abnormality, amnesia, hyperkinesia, hypertension, decreased libido, and visual disturbance, including punctate subepithelial or other corneal opacity, corneal edema, decreased visual acuity, sensitivity to light, and optic nerve palsy.
Rare (less than 0.1%) occurring adverse reactions are: instances of convulsion, leukopenia, neutropenia, eczematoid dermatitis, oculogyric episodes, suicidal attempt, suicide, and suicidal ideation (see WARNINGS ) . Other adverse reactions reported during post-marketing experience with amantadine hydrochloride usage include: Nervous System/Psychiatric – coma, stupor, delirium, hypokinesia, hypertonia, delusions, aggressive behavior, paranoid reaction, manic reaction, involuntary muscle contractions, gait abnormalities, paresthesia, EEG changes, and tremor.
Abrupt discontinuation may also precipitate delirium, agitation, delusions, hallucinations, paranoid reaction, stupor, anxiety, depression, and slurred speech Cardiovascular – cardiac arrest, arrhythmias including malignant arrhythmias, hypotension and tachycardia; Respiratory – acute respiratory failure, pulmonary edema, and tachypnea; Gastrointestinal – dysphagia; Hematologic – leukocytosis, agranulocytosis; Special Senses – keratitis, mydriasis and corneal edema; Skin and Appendages – pruritus and diaphoresis; Miscellaneous – neuroleptic malignant syndrome (see WARNINGS ) , allergic reactions including anaphylactic reactions, edema, and fever.
Laboratory Test – elevated: CPK, BUN, serum creatinine, alkaline phosphatase, LDH, bilirubin, GGT, SGOT, and SGPT.
🔄 Drug Interactions ▾
Drug Interactions Careful observation is required when amantadine hydrochloride is administered concurrently with central nervous system stimulants. Agents with anticholinergic properties may potentiate the anticholinergic-like side effects of amantadine. Coadministration of thioridazine has been reported to worsen the tremor in elderly patients with Parkinson's disease, however, it is not known if other phenothiazines produce a similar response.
Coadministration of Dyazide (triamterene/hydrochlorothiazide) resulted in a higher plasma amantadine concentration in a 61-year-old man receiving amantadine hydrochloride 100 mg TID for Parkinson's disease. 1 It is not known which of the components of Dyazide contributed to the observation or if related drugs produce a similar response. Coadministration of quinine or quinidine with amantadine was shown to reduce the renal clearance of amantadine by about 30%.
The concurrent use of amantadine hydrochloride with live attenuated influenza vaccine (LAIV) intranasal has not been evaluated. However, because of the potential for interference between these products, LAIV should not be administered within 2 weeks before or 48 hours after administration of amantadine hydrochloride, unless medically indicated. The concern about possible interference arises from the potential for antiviral drugs to inhibit replication of live vaccine virus.
Trivalent inactivated influenza vaccine can be administered at any time relative to use of amantadine hydrochloride.
🤰 Pregnancy ▾
Pregnancy Teratogenic Effects The effect of amantadine on embryofetal and peri-postnatal development has not been adequately tested, that is, in studies conducted under Good Laboratory Practice (GLP) and according to current recommended methodology. However, in two non-GLP studies in rats in which females were dosed from 5 days prior to mating to Day 6 of gestation or on Days 7 to 14 of gestation, amantadine hydrochloride produced increases in embryonic death at an oral dose of 100 mg/kg (or 3 times the maximum recommended human dose on a mg/m 2 basis).
In the non-GLP rat study in which females were dosed on Days 7 to 14 of gestation, there was a marked increase in severe visceral and skeletal malformations at oral doses of 50 and 100 mg/kg (or 1.5 and 3 times, respectively, the maximum recommended human dose on a mg/m 2 basis). The no-effect dose for teratogenicity was 37 mg/kg (equal to the maximum recommended human dose on a mg/m 2 basis). The safety margins reported may not accurately reflect the risk considering the questionable quality of the study on which they are based.
There are no adequate and well-controlled studies in pregnant women. Human data regarding teratogenicity after maternal use of amantadine is scarce. Tetralogy of Fallot and tibial hemimelia (normal karyotype) occurred in an infant exposed to amantadine during the first trimester of pregnancy (100 mg P.O. for 7 days during the 6 th and 7 th week of gestation).
Cardiovascular maldevelopment (single ventricle with pulmonary atresia) was associated with maternal exposure to amantadine (100 mg/d) administered during the first 2 weeks of pregnancy. Amantadine hydrochloride should be used during pregnancy only if the potential benefit justifies the potential risk to the embryo or fetus.
🧒 Pediatric Use ▾
Pediatric Use The safety and efficacy of amantadine hydrochloride in newborn infants and infants below the age of 1 year have not been established.
🧓 Geriatric Use ▾
Usage in the Elderly Because amantadine hydrochloride is primarily excreted in the urine, it accumulates in the plasma and in the body when renal function declines. Thus, the dose of amantadine hydrochloride should be reduced in patients with renal impairment and in individuals who are 65 years of age or older. The dose of amantadine hydrochloride tablets may need reduction in patients with congestive heart failure, peripheral edema, or orthostatic hypotension (see DOSAGE AND ADMINISTRATION ) .
🆘 Overdosage ▾
OVERDOSAGE Deaths have been reported from overdose with amantadine hydrochloride. The lowest reported acute lethal dose was 1 gram. Because some patients have attempted suicide by overdosing with amantadine, prescriptions should be written for the smallest quantity consistent with good patient management.
Acute toxicity may be attributable to the anticholinergic effects of amantadine. Drug overdose has resulted in cardiac, respiratory, renal, or central nervous system toxicity. Cardiac dysfunction includes arrhythmia, tachycardia, and hypertension.
Pulmonary edema and respiratory distress (including adult respiratory distress syndrome – ARDS) have been reported; renal dysfunction including increased BUN, decreased creatinine clearance and renal insufficiency can occur. Central nervous system effects that have been reported include insomnia, anxiety, agitation, aggressive behavior, hypertonia, hyperkinesia, ataxia, gait abnormality, tremor, confusion, disorientation, depersonalization, fear, delirium, hallucinations, psychotic reactions, lethargy, somnolence, and coma.
Seizures may be exacerbated in patients with prior history of seizure disorders. Hyperthermia has also been observed in cases where a drug overdose has occurred. There is no specific antidote for an overdose of amantadine hydrochloride.
However, slowly administered intravenous physostigmine in 1 mg and 2 mg doses in an adult 2 at 1 to 2 hour intervals and 0.5 mg doses in a child 3 at 5 to 10 minute intervals up to a maximum of 2 mg/hour have been reported to be effective in the control of central nervous system toxicity caused by amantadine hydrochloride. For acute overdosing, general supportive measures should be employed along with immediate gastric lavage or induction of emesis. Fluids should be forced, and if necessary, given intravenously.
The pH of the urine has been reported to influence the excretion rate of amantadine hydrochloride. Since the excretion rate of amantadine hydrochloride increases rapidly when the urine is acidic, the administration of urine acidifying drugs may increase the elimination of the drug from the body. The blood pressure, pulse, respiration and temperature should be monitored.
The patient should be observed for hyperactivity and convulsions; if required, sedation, and anticonvulsant therapy should be administered. The patient should be observed for the possible development of arrhythmias and hypotension; if required, appropriate antiarrhythmic and antihypotensive therapy should be given. Electrocardiographic monitoring may be required after ingestion, since malignant tachyarrhythmias can appear after overdose.
Care should be exercised when administering adrenergic agents, such as isoproterenol, to patients with an amantadine hydrochloride overdose, since the dopaminergic activity of amantadine hydrochloride has been reported to induce malignant arrhythmias. The blood electrolytes, urine pH and urinary output should be monitored. If there is no record of recent voiding, catheterization should be done.
🧬 Clinical Pharmacology ▾
CLINICAL PHARMACOLOGY Pharmacodynamics Mechanism of Action Antiviral The mechanism by which amantadine exerts its antiviral activity is not clearly understood. It appears to mainly prevent the release of infectious viral nucleic acid into the host cell by interfering with the function of the transmembrane domain of the viral M2 protein. In certain cases, amantadine is also known to prevent virus assembly during virus replication.
It does not appear to interfere with the immunogenicity of inactivated influenza A virus vaccine. Antiviral Activity Amantadine inhibits the replication of influenza A virus isolates from each of the subtypes, i.e., H1N1, H2N2 and H3N2. It has very little or no activity against influenza B virus isolates.
A quantitative relationship between the in vitro susceptibility of influenza A virus to amantadine and the clinical response to therapy has not been established in man. Sensitivity test results, expressed as the concentration of amantadine required to inhibit by 50% the growth of virus (ED 50 ) in tissue culture vary greatly (from 0.1 mcg/mL to 25 mcg/mL) depending upon the assay protocol used, size of virus inoculum, isolates of influenza A virus strains tested, and the cell type used. Host cells in tissue culture readily tolerated amantadine up to a concentration of 100 mcg/mL.
Drug Resistance Influenza A variants with reduced in vitro sensitivity to amantadine have been isolated from epidemic strains in areas where adamantane derivatives are being used. Influenza viruses with reduced in vitro sensitivity have been shown to be transmissible and to cause typical influenza illness. The quantitative relationship between the in vitro sensitivity of influenza A variants to amantadine and the clinical response to therapy has not been established.
Mechanism of Action Parkinson's Disease The mechanism of action of amantadine hydrochloride in the treatment of Parkinson's disease and drug-induced extrapyramidal reactions is not known. Data from earlier animal studies suggest that amantadine hydrochloride may have direct and indirect effects on dopamine neurons. More recent studies have demonstrated that amantadine is a weak, non-competitive NMDA receptor antagonist (K i = 10µM).
Although amantadine has not been shown to possess direct anticholinergic activity in animal studies, clinically, it exhibits anticholinergic-like side effects such as dry mouth, urinary retention, and constipation. Pharmacokinetics Amantadine hydrochloride is well absorbed orally. Maximum plasma concentrations are directly related to dose for doses up to 200 mg/day.
Doses above 200 mg/day may result in a greater than proportional increase in maximum plasma concentrations. It is primarily excreted unchanged in the urine by glomerular filtration and tubular secretion. Eight metabolites of amantadine have been identified in human urine.
One metabolite, an N-acetylated compound, was quantified in human urine and accounted for 5% to 15% of the administered dose. Plasma acetylamantadine accounted for up to 80% of the concurrent amantadine plasma concentration in 5 of 12 healthy volunteers following the ingestion of a 200 mg dose of amantadine. Acetylamantadine was not detected in the plasma of the remaining seven volunteers.
The contribution of this metabolite to efficacy or toxicity is not known. There appears to be a relationship between plasma amantadine concentrations and toxicity. As concentration increases, toxicity seems to be more prevalent, however, absolute values of amantadine concentrations associated with adverse effects have not been fully defined.
Amantadine pharmacokinetics were determined in 24 normal adult male volunteers after the oral administration of a single amantadine hydrochloride 100 mg soft gel capsule. The mean ± SD maximum plasma concentration was 0.22 ± 0.03 mcg/mL (range: 0.18 to 0.32 mcg/mL). The time to peak concentration was 3.3 ± 1.5 hours (range: 1.5 to 8 hours).
The apparent oral clearance was 0.28 ± 0.…
🧬 Mechanism of Action ▾
Mechanism of Action Antiviral The mechanism by which amantadine exerts its antiviral activity is not clearly understood. It appears to mainly prevent the release of infectious viral nucleic acid into the host cell by interfering with the function of the transmembrane domain of the viral M2 protein. In certain cases, amantadine is also known to prevent virus assembly during virus replication.
It does not appear to interfere with the immunogenicity of inactivated influenza A virus vaccine.
Mechanism of Action Parkinson's Disease The mechanism of action of amantadine hydrochloride in the treatment of Parkinson's disease and drug-induced extrapyramidal reactions is not known. Data from earlier animal studies suggest that amantadine hydrochloride may have direct and indirect effects on dopamine neurons. More recent studies have demonstrated that amantadine is a weak, non-competitive NMDA receptor antagonist (K i = 10µM).
Although amantadine has not been shown to possess direct anticholinergic activity in animal studies, clinically, it exhibits anticholinergic-like side effects such as dry mouth, urinary retention, and constipation.
📦 How Supplied / Storage and Handling ▾
HOW SUPPLIED Amantadine hydrochloride tablets, USP are available as peach, compressed tablets, round, debossed "832" on one side and "AMT" on the other side. They are supplied as follows: Bottles of 100 with a child-resistant closure, NDC 0832-0111-00 Bottles of 500, NDC 0832-0111-50 Unit-Dose Cartons of 100, NDC 0832-0111-03 (10 cards containing 10 tablets each) Store at 20° to 25°C (68° to 77°F); excursions permitted to 15° to 30°C (59° to 86°F) [See USP Controlled Room Temperature]. Protect from light and moisture.
Dispense in a tight, light-resistant container as defined in the USP, with a child-resistant closure (as required). Keep out of reach of children .
📦 Storage and Handling ▾
Store at 20° to 25°C (68° to 77°F); excursions permitted to 15° to 30°C (59° to 86°F) [See USP Controlled Room Temperature]. Protect from light and moisture. Dispense in a tight, light-resistant container as defined in the USP, with a child-resistant closure (as required). Keep out of reach of children .
📋 Description ▾
DESCRIPTION Amantadine hydrochloride, USP is designated generically as amantadine hydrochloride, USP and chemically as 1-adamantanamine hydrochloride. C 10 H 17 N∙HCl Amantadine hydrochloride, USP is a stable white or nearly white crystalline powder, freely soluble in water and soluble in alcohol and in chloroform. Amantadine hydrochloride, USP has pharmacological actions as both an anti-Parkinson and an antiviral drug.
Each tablet intended for oral administration contains 100 mg amantadine hydrochloride, USP and has the following inactive ingredients: microcrystalline cellulose, povidone, sodium starch glycolate, magnesium stearate, colloidal silicon dioxide and FD&C Yellow No. 6 Aluminum Lake. Meets USP Dissolution Test 2 Chemical Structure
💬 Information for Patients ▾
Information for Patients Patients should be advised of the following information: Blurry vision, eye pain, loss of vision and/or impaired mental acuity may occur. Gradually increase physical activity as the symptoms of Parkinson's disease improve. Avoid excessive alcohol usage, since it may increase the potential for CNS effects such as dizziness, confusion, lightheadedness, and orthostatic hypotension.
Avoid getting up suddenly from a sitting or lying position. If dizziness or lightheadedness occurs, notify physician. Notify physician if mood/mental changes, swelling of extremities, difficulty urinating and/or shortness of breath occur.
Do not take more medication than prescribed because of the risk of overdose. If there is no improvement in a few days, or if medication appears less effective after a few weeks, discuss with a physician. Consult physician before discontinuing medication.
Seek medical attention immediately if it is suspected that an overdose of medication has been taken.