Notes
Distributed by Medsurge Healthcare Pty Ltd
1 Name of Medicine
Amantadine hydrochloride.
2 Qualitative and Quantitative Composition
Each capsule contains amantadine hydrochloride 100 mg.
Excipients with known effect. Lactose monohydrate and may contain traces of sulfites. For the full list of excipients, see Section 6.1 List of Excipients.
3 Pharmaceutical Form
Amantadine hydrochloride 100 mg is packed in size 4, plain hard gelatin capsules with brown cap and red body. The body and cap are marked with the number 100 in black ink.
4 Clinical Particulars
4.9 Overdose
Overdose (acute overdose with multiples of the maximum recommended dose or overexposure due to high dosages for elderly and/or renally impaired patients) with amantadine hydrochloride capsules can lead to a fatal outcome (see Section 4.4 Special Warnings and Precautions for Use).
Signs and symptoms. Neuromuscular disturbances and symptoms of acute psychosis are prominent features of acute poisoning with amantadine.
Central nervous system. Hyperreflexia; motor restlessness; convulsions; extrapyramidal signs: torsion spasms, dystonic posturing; confusion; disorientation; delirium; visual hallucinations; dilated pupils; dysphagia, and myoclonus, aggression/hostility, depressed level of consciousness and coma.
Respiratory system. Hyperventilation, pulmonary oedema, respiratory distress including adult respiratory distress syndrome.
Cardiovascular system. Disturbances of fluid, electrolyte and acid-base balance, sinus tachycardia, arrhythmia, and hypertension. Cardiac arrest and sudden cardiac death have been reported.
Gastrointestinal system. Nausea, vomiting, dry mouth.
Renal function. Urinary retention, renal dysfunction including increase in blood urea nitrogen (BUN) and decreased creatinine clearance.
Overdose from combined drug treatment. The peripheral and central adverse effects of anticholinergic drugs are increased by the concomitant use of amantadine, and acute psychotic reactions, which may be identical to those caused by atropine poisoning, may occur, especially when large doses of anticholinergic agents are used (see Section 4.5 Interactions with Other Medicines and Other Forms of Interactions). When overdosage of amantadine has occurred in conjunction with the use of alcohol or central nervous system stimulants, the signs and symptoms of acute poisoning with Amantamed may be aggravated or otherwise modified.
Treatment. There is no specific amantadine hydrochloride antidote.
Removal and/or inactivation of poisoning agent(s). Induction of vomiting and/or gastric aspiration and lavage if patient is conscious, activated charcoal, saline cathartic, if judged appropriate. Since amantadine is largely excreted unchanged in the urine, maintenance of renal excretory function, copious diuresis, and forced diuresis, if necessary, are effective in removing it from the blood stream. Acidification of the urine favours the excretion of amantadine in the urine. Haemodialysis does not remove significant amounts of amantadine.
Monitoring of blood pressure, heart rate, ECG, respiration, body temperature, and treatment for possible hypotension and cardiac arrhythmias, as necessary. Caution is required when administering adrenergic substances in case of cardiac arrhythmias and hypotension as the clinical status may deteriorate due to arrhythmogenic nature of the adrenergic drugs.
Convulsions and excessive motor restlessness. Administer anticonvulsants such as diazepam I.V., paraldehyde I.M. or per rectum, or phenobarbital I.M.
Acute psychotic symptoms, delirium, dystonic posturing, myoclonic manifestations. Physostigmine by slow I.V. infusion (1 mg doses in adults, 0.5 mg in children) in repeated administration according to initial response and subsequent need has been reported.
Retention of urine. The bladder should be catheterized; an indwelling catheter can be left in place for the time required.
For information on the management of overdose, contact the Poisons Information Centre on 13 11 26 (Australia).
5 Pharmacological Properties
5.3 Preclinical Safety Data
Genotoxicity. No data available.
Carcinogenicity. No data available.
6 Pharmaceutical Particulars
6.7 Physicochemical Properties
The active ingredient, amantadine hydrochloride, is a white or almost crystalline powder, freely soluble in water, and in alcohol. It sublimes on being heated.
Chemical structure. Chemical name: 1-adamantanamine hydrochloride.
Molecular weight: 187.7.
Molecular formula: C10H17N.HCl.
https://stagingapi.mims.com/au/public/v2/images/fullchemgif/CSAMAHYD.gif CAS number. 665-66-7.
7 Medicine Schedule (Poisons Standard)
(S4) Prescription Only Medicine.
Summary Table of Changes
https://stagingapi.mims.com/au/public/v2/images/fulltablegif/AMANTAST.gif
