Amantadine

Amantadine hydrochloride [665-66-7] (1-adamantanamine hydrochloride, 41), C qH N HQ., (93) is a good example of a narrow-spectmm agent active only against influenza A vims. It became the first antiviral dmg available for systemic use in the United States when it was approved by the FDA in 1966 for use against Asian influenza. In 1976, FDA approval was extended to the use of amantadine for the reHef of symptoms of all influenza A strains. Amantadine is marketed by Du Pont de Nemours Co., Inc. A stmcturaHy related dmg, rimantadine hydrochloride [1501 -84-4] C 2H2 N HQ, (a-methyl-l-adamantanemethylamine hydrochloride, 42), is widely used in Russia to treat influenza A vims (94). 

Both amantadiae and rknantadiae have been found to reduce the duration of influenza A-iaduced fever and malaise, and to lessen viral shedding. Prophylactic treatment has been recommended for high risk patients (95). It has been suggested that, ia the presence of amantadine, the influenza vims attaches normally to cells, but once iaside the ceU the vims fails to initiate repHcation. Thus amantadine appears to inhibit the initiation of transcription at an early stage between uncoating and viral-specific RNA synthesis (96). 

Amantadine is an antiviral agent that is active against influenza A infection and against some strains of H5NX avian flu. Draw a three-dimensional representation of amantadine showing the chair cyclohexane rings. 

Low affinity use-dependent NMDA recqrtor antagonists meet the criteria for safe administration into patients. Drugs like amantadine and memantine have modest effects on Parkinson s disease and are used as initial therapy or as adjunct to l-DOPA. Their adverse effects include dizziness, lethargy and sleep disturbance. 

Adverse reactions of amantadine include gastrointestinal upset with nausea and vomiting, anorexia, asthenia (weakness, loss of strength), constipation, depression, visual disturbances, psychosis, urinary retention, and orthostatic hypotension. 

Amantadine is used cautiously in patients with seizure disorders, psychiatric problems, renal impairment, and cardiac disease. Amantadine is a Pregnancy Category B drug and is used cautiously during pregnancy and lactation. Concurrent use of antihistamines, phenothiazines, tricyclic antidepressants, disopyramide, and quinidine may increase the anticholinergic effects (dry mouth, blurred vision, constipation) of amantadine... 

AMANTADINE The nurse administers this drug for the prevention or treatment of respiratory tract illness caused by influenza A virus. Some patients are prescribed this drug to manage extrapyramidal effects caused by drugp used to treat Parkinsonism (See Chaps. 29 and 32). The nurse should protect the capsules from moisture to prevent deterioration. When the drug is administered for symptoms of influenza, it is important to start therapy within 24 to 48 hours after symptoms begin. 

AMANTADINE The nurse should monitor the patient for the occurrence of drowsiness, dizziness, light-headedness, or mood changes (irritability or mood change). 

Dopaminergic drug are drug that affect the dopamine content of the brain. These drag include levodopa (Larodopa), carbidopa(Ladosyn), amantadine (Symmetrel),... 

The mechanism of action of amantadine (Symmetrel) and selegiline (Eldepryl) in die treatment of parkinsonism is not fully understood. 

Amantadine is less effective than levodopa in the treatment of Fhrkinson s disease but more effective than die anticholinergics. Amantadine may be given alone or in combination witii an antiparkinsonism drug witii anticholinergic activity. Amantadine is also used as an antiviral drug (see Chap. 14). 

The most common serious adverse reactions to amantadine are orthostatic hypotension, depression, congestive heart failure, psychosis, urinary retention, convulsions, leukopenia, and neutropenia Less serious reactions include hallucinations, confusion, anxiety, anorexia, nausea, and constipation. Adverse reactions with selegiline include nausea, hallucinations, confusion, depression, loss of balance, and dizziness. 

Ms. Dennis, age 89 years, has Parkinson s disease and is taking amantadine daily. In discussing her care with the family, determine what information you would include in the teaching plan and what information would be most important for the family to understand. Explain your answer. 

C2H2N 75-05-8) see Amantadine Clofedanol Dorzolamide Ethambutol Gabapentin Ritonavir 5-acetonyl-2-methoxybenzenesulfonamide (C10H13NO4S 116091-63-5) see Tarnsulosin hydrochloride acetophenone... 

Because chronic cocaine use appears to reduce the efficiency of central dopamine neurotransmission, a number of dopaminergic compounds, including amantadine, bromocriptine, mazindol, and methylphenidate, have been examined as treatments for cocaine abuse. It is thought that these relatively slow-onset dopaminergic agents, with low or relatively low abuse potential, would correct the dopamine dysregulation and alleviate withdrawal symptoms following chronic stimulant use. 

Two classes of inhibitors for influenza virus are currently available (Hayden 2006). The M2 proton channel inhibitors amantadine and rimantadine and the neuraminidase (NA) inhibitors oseltamivir carboxylate and zanamivir. Chapter 5 provides more details about the class of NA inhibitors. 

Abed Y, Goyette N, Boivin G (2005) Generation and characterization of recombinant influenza A (HlNl) viruses harboring amantadine resistance mutations, Antimicrob Agents Chemother 49 556-559... 

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