Dosing & Uses
Dosage Forms & Strengths
Serious illness or high dose of other antiparkinson agents: 100 mg/day PO initially; may be increased to 100 mg q12hr after at least 1 week
Up to 400 mg/day, but only in special circumstances
Drug-Induced Extrapyramidal Symptoms
100 mg PO q12hr; not to exceed 300 mg/day
Levodopa-induced Dyskinesia (Orphan)
Orphan designation for treatment of levodopa-induced dyskinesia
- Osmotica Pharmaceutical Corporation; Regulatory, Clinical Operations & Legal; Lumina Station #2, Suite 209-A; Wilmington, NC 28403
- CrCl 30-50 mL/min: 200 mg PO on 1st day, then 100 mg/day PO
- CrCl 15-29 mL/min: 200 mg PO on 1st day, then 100 mg PO every other day
- CrCl <15 mL/min; hemodialysis: 200 mg PO weekly
Dosage Forms & Strengths
Influenza A Treatment
NOTE: Because of resistance, amantadine is no longer recommended for prophylaxis or treatment of influenza A; refer to current ACIP recommendations
1-9 years or <40 kg (any age): 5 mg/kg/day PO in single dose or divided q12 hr; not to exceed 150 mg/day
≥10 years and <40 kg: 5 mg/kg/day PO divided q12hr
≥10 years and ≥40 kg: 100 mg PO q12hr
>65 years: Therapy should be based on renal function
Serious - Use Alternative
Significant - Monitor Closely
Instances of convulsions
Hypersensitivity to amantadine, rimantadine
Untreated narrow-angle glaucoma
Since 2008-09 influenza season, Centers for Disease Control and Prevention (CDC) advises against use for treatment or prophylaxis of influenza in US
CHF, peripheral edema, orthostatic hypotension
Renal impairment, liver disease
History of seizures, eczematoid rash, severe psychosis or psychoneurosis
Dosages >200 mg/day
Consider reducing anticholinergic dosages before initiating amantadine therapy
Avoid abrupt withdrawal
Risk of neuroleptic malignant syndrome (NMS) with dosage reduction or withdrawal
May impair ability to perform hazardous tasks
Possibility of reduced effectiveness after several months; may regain efficacy if dosage is increased
- Risk of uncontrollable sexual, gambling, or other urges
- May be linked to higher melanoma risk
Pregnancy & Lactation
Pregnancy category: C
Lactation: Drug enters breast milk; not recommended
A:Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B:May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C:Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D:Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X:Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA:Information not available.
Mechanism of Action
Prevents release of infectious viral nucleic acid
May promote dopamine release from presynaptic fibers or block reuptake of dopamine into presynaptic neurons
Onset: Within 48 hr (antidyskinetic)
Peak plasma time: 2-4 hr
Peak plasma concentration (100-mg single dose): 0.24 mcg/mL
Protein bound: 67%
Vd: 1.5-6.1 L/kg (normal renal function)
Not appreciably metabolized; small amounts of acetyl metabolite identified
Half-life: 16 hr (average with normal renal function)
Total body clearance: 0.2-0.3 L/hr/kg
Excretion: Urine (80-90% unchanged) by glomerular filtration and tubular secretion
Administer daily dose in 2 divided doses to decrease adverse CNS effects
Administer 2nd dose several hours before bedtime to minimize insomnia
Adding plans allows you to compare formulary status to other drugs in the same class.
To view formulary information first create a list of plans. Your list will be saved and can be edited at any time.
Adding plans allows you to:
- View the formulary and any restrictions for each plan.
- Manage and view all your plans together – even plans in different states.
- Compare formulary status to other drugs in the same class.
- Access your plan list on any device – mobile or desktop.
The above information is provided for general informational and educational purposes only. Individual plans may vary and formulary information changes. Contact the applicable plan provider for the most current information.
|1||This drug is available at the lowest co-pay. Most commonly, these are generic drugs.|
|2||This drug is available at a middle level co-pay. Most commonly, these are "preferred" (on formulary) brand drugs.|
|3||This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs.|
|4||This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.|
|5||This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.|
|6||This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.|
|NC||NOT COVERED – Drugs that are not covered by the plan.|
Drugs that require prior authorization. This restriction requires that specific clinical criteria be met prior to the approval of the prescription.
Drugs that have quantity limits associated with each prescription. This restriction typically limits the quantity of the drug that will be covered.
Drugs that have step therapy associated with each prescription. This restriction typically requires that certain criteria be met prior to approval for the prescription.
Drugs that have restrictions other than prior authorization, quantity limits, and step therapy associated with each prescription.