AMANTIX
PolandThe medicine is used to reduce the severity of Parkinson's disease symptoms (such as stiffness, tremors, decreased mobility, or immobility) and to treat movement disorders induced by certain drugs (e.g., neuroleptics).
Frequently asked questions
How should Amantix be taken?
Tablets should be taken orally with a small amount of liquid, preferably in the morning and afternoon. The last dose of the day should not be taken later than 4:00 PM. The dosage is determined individually by a physician and usually starts at 1 tablet per day, with a gradual increase in dose.
When should you not use this medicine?
Do not use the medicine if you are allergic to amantadine, have severe heart failure, cardiomyopathy, myocarditis, cardiac arrhythmia, bradycardia (below 55 beats per minute), certain ECG changes, potassium or magnesium deficiency in the blood, or in cases of pregnancy or breastfeeding.
Which medicines should be used with caution while taking Amantix?
Particular caution should be exercised if taking medicines that prolong the QT interval (e.g., certain antiarrhythmics, antipsychotics, antidepressants, certain antibiotics, or antifungals), anticholinergic drugs, and memantine. Combining the medicine with certain diuretics should also be avoided.
What side effects can Amantix cause?
Common side effects include: sleep disturbances, anxiety, agitation, nausea, dizziness, dry mouth, urinary retention, and a sudden drop in blood pressure upon standing. Less commonly, vision problems, muscle cramps, or seizures may occur. Some female patients may experience an irresistible urge to behave in an unusual manner (e.g., gambling, excessive eating).
What should I do if vision or heart problems occur?
If blurred vision or loss of visual acuity occurs, contact an ophthalmologist immediately. In case of heart palpitations, dizziness, or fainting, stop using the medicine immediately and consult a doctor to check heart function.
Can I drink alcohol during treatment?
Alcoholic beverages should be avoided while taking the medicine, as it reduces alcohol tolerance.
Instructions for use
Package leaflet: Information for the user
Warning! Keep the leaflet – information on the immediate packaging is in a foreign language!
Amantix (PK-Merz)
100 mg, coated tablets
Amantadini sulfas
Amantix and PK-Merz are different trade names for the same medicinal product.
Please read this leaflet carefully before using this medicine, as it contains important information for the patient.
- Keep this leaflet to be able to read it again if necessary.
- If you have any doubts, please consult your doctor or pharmacist.
- This medicine has been prescribed for a specific individual. Do not pass it on to others. This medicine may harm someone else, even if their symptoms are identical.
- If you experience any adverse reactions, including any not listed in this leaflet, inform your doctor or pharmacist. See section 4.
Table of contents of the leaflet:
- What Amantix is and what it is used for
- Important information before taking Amantix
- How to take Amantix
- Possible side effects
- How to store Amantix
- Contents of the pack and other information
1. What Amantix is and what it is used for
Amantix is a dopaminergic medicinal product, meaning it may increase levels of certain chemical substances that transmit nerve impulses in the nervous system, including the brain.
Amantix reduces the severity of symptoms of Parkinson's disease (an antiparkinsonian agent).
Amantix tablets are used:
- in the treatment of symptoms of Parkinson's disease, such as rigidity, tremor, hypokinesia (reduced motor function), or akinesia (lack of movement);
- in the treatment of movement disorders resembling Parkinson's disease caused by certain medicines (neuroleptics and drugs with a similar mechanism of action) (extrapyramidal symptoms, such as early dyskinesia, an uncontrollable urge to move (akathisia), and parkinsonism).
2. Important information before using Amantix medicine
When not to use Amantix:
- if the patient is allergic to amantadine or any of the other ingredients of this medicine (listed in section 6);
- if the patient has severe, uncontrolled heart failure (NYHA class IV);
- if the patient has heart diseases such as cardiomyopathy or myocarditis;
- if the patient has disturbances in the conduction of electrical impulses within the heart (second- or third-degree atrioventricular block);
- if the patient has a slow heart rate (less than 55 beats per minute);
- if the patient has changes in the electrocardiogram (ECG), such as prolonged QT interval, visible U waves, or if there is a family history of congenital long QT syndrome;
- if the patient has severe heart rhythm disorders (ventricular arrhythmias, including a history of torsades de pointes);
- if the patient has low blood levels of potassium or magnesium;
- if the patient is pregnant or breastfeeding;
- if the patient is taking medicines that prolong the QT interval (see section 2 – Amantix and other medicines).
Warnings and precautions
Before starting treatment with Amantix, discuss this with your doctor or pharmacist.
Special caution is required when using Amantix in patients with:
- benign prostatic hyperplasia (enlarged prostate);
- increased intraocular pressure (narrow-angle glaucoma);
- kidney impairment of varying severity (risk of drug accumulation due to reduced renal filtration) (see section 3);
- current or past episodes of agitation or confusion (disorientation);
- psychiatric disorders (history of delirium or exogenous psychoses);
- diarrhoea, vomiting, use of diuretics or insulin in emergency conditions, kidney disease, or anorexia (risk of water-electrolyte imbalance);
- patients concurrently treated with memantine (see section 2 – Amantix and other medicines).
Other important information about using Amantix
Before starting treatment and after 1 and 3 weeks of therapy, an ECG should be performed and the QT interval corrected using Bazett's formula (QTc) should be determined. An ECG should also be performed before any dose increase and 2 weeks after each dose increase. Subsequent follow-up ECGs should be performed at least once a year.
In patients with cardiac pacemakers, accurate assessment of the QT interval duration is not possible; therefore, the decision to use Amantix should be made individually for each patient after consultation with a cardiologist.
In patients with impaired kidney function, accumulation of the drug may occur due to reduced renal excretion. This may lead to symptoms associated with overdose. The doctor should carefully adjust the dose and monitor glomerular filtration rate (see section 3).
Particular caution should be exercised when using Amantix in patients with organic brain syndrome or a history of seizures, due to the possible worsening of symptoms and risk of seizures (see sections 3 and 4).
During treatment with Amantix, the doctor must regularly monitor patients prone to seizures, including those with a previous history of seizures and those with cardiovascular diseases.
If during treatment with Amantix the patient experiences palpitations, dizziness, or brief loss of consciousness (fainting), treatment with Amantix should be stopped immediately and the patient should consult a doctor to assess heart function (heart rhythm) via 24-hour monitoring. If the doctor does not detect any disturbances in heart function, treatment with Amantix may be continued, taking into account contraindications and interactions (see section 4).
Patients treated simultaneously with neuroleptics (medicines used to treat psychiatric disorders) and Amantix are at risk of developing a life-threatening condition known as neuroleptic malignant syndrome if Amantix is abruptly discontinued.
This syndrome is characterised by sudden high fever, muscle rigidity, and autonomic nervous system dysfunction.
In patients with Parkinson's disease, clinical symptoms such as low blood pressure, drooling, sweating, elevated body temperature, fluid retention, and depression are often observed. When using Amantix in these patients, particular attention should be paid to its adverse effects and interactions.
Patients experiencing difficulty urinating should contact their doctor.
If a patient develops blurred vision or other visual disturbances, they should immediately contact an ophthalmologist.
Inform the doctor if the patient or family members or (and) caregivers notice that the patient has urges or irresistible desires to behave in an unusual way and cannot resist these impulses, or experiences urges or compulsions to act in a way that could be harmful to themselves or others. These are known as impulse control disorders, which may include behaviours such as pathological gambling, compulsive eating or spending, abnormally increased sexual drive, or intensified sexual thoughts or feelings. The doctor may modify the dose or discontinue Amantix.
Amantadine should be avoided for the prevention and treatment of influenza A virus infection due to the risk of overdose.
Children and adolescents
There is no data available on the use of this medicine in children and adolescents.
Elderly patients
In elderly patients, the dose should be carefully selected, especially in cases of agitation, confusion, or delirium (see section 3).
Amantix and other medicines
Inform your doctor about all medicines currently or recently taken, as well as any medicines the patient plans to take.
Amantix must not be used concurrently with other medicines that prolong the QT interval, such as:
- certain medicines used to treat irregular heart rhythms (antiarrhythmics of class IA, e.g. quinidine, disopyramide, procainamide, and class III, e.g. amiodarone, sotalol);
- certain medicines used to treat psychiatric disorders (antipsychotics, e.g. thioridazine, chlorpromazine, haloperidol, pimozide);
- certain medicines used to treat depression (tricyclic and tetracyclic antidepressants, e.g. amitriptyline);
- certain medicines used to treat allergies, e.g. hay fever (antihistamines, e.g. astemizole, terfenadine);
- certain medicines used to treat bacterial infections (macrolide antibiotics, e.g. erythromycin, clarithromycin, and gyrase inhibitors, e.g. sparfloxacin);
- certain medicines used to treat fungal infections (azole antifungals);
- other medicines such as budipine, halofantrine, cotrimoxazole, pentamidine, cisapride, or bepridil.
The above list may not be complete. Before using Amantix together with another medicine, the doctor should check the possibility of interactions leading to QT interval prolongation.
Combination therapy with Amantix and other medicines used in Parkinson's disease may be possible. To avoid adverse effects (e.g. psychotic reactions), it may be necessary to reduce the dose of one or both medicines.
Concurrent use of Amantix with any of the following medicines or active substances may lead to the following interactions:
Anticholinergics
Increased adverse effects (confusion and hallucinations) of anticholinergic medicines (e.g. trihexyphenidyl, benzatropine, scopolamine, biperiden, orphenadrine).
Indirectly acting central sympathomimetics
Enhanced central effects of amantadine.
Levodopa (medicine used in Parkinson's disease)
Mutual enhancement of therapeutic effect (therefore levodopa may be administered concurrently with Amantix).
Memantine (medicine used in dementia)
Memantine may enhance the effects and adverse effects of Amantix (see section 2 – Warnings and precautions).
Other medicines
Concurrent use of diuretics containing triamterene in combination with hydrochlorothiazide may reduce the plasma clearance of amantadine, leading to toxic serum concentrations. Therefore, concurrent use of amantadine and such medicines should be avoided.
It should be noted that the interactions listed above may also apply to medicines previously used.
Taking Amantix with food, drinks and alcohol
Alcoholic beverages should be avoided during treatment with Amantix, as this medicine reduces alcohol tolerance.
Pregnancy and breastfeeding
If the patient is pregnant or breastfeeding, suspects she may be pregnant, or is planning to have a child, she should consult a doctor or pharmacist before using this medicine.
Amantix tablets are contraindicated during pregnancy and in women who are breastfeeding.
Driving and operating machinery
The effect of Amantix on concentration, wakefulness, and ocular accommodation (the eye's ability to adjust to different distances) cannot be ruled out, especially in combination with other medicines used to treat Parkinson's disease.
At the beginning of treatment, the ability to drive and operate machinery may be further impaired beyond the impairment caused by the disease itself.
The patient may be unable to react quickly and decisively in unexpected or sudden situations.
Driving vehicles and operating machinery or electrical devices should not be undertaken without consulting a doctor.
Bear in mind that alcohol may worsen the impairment of driving ability.
Amantix contains lactose monohydrate and sunset yellow (E 110)
Amantix contains lactose monohydrate. Patients with intolerance to certain sugars should consult their doctor before starting this medicine.
Amantix contains a colouring agent – sunset yellow (E 110), which may cause allergic reactions.
3. How to use Amantix
This medicine should always be taken as directed by the physician. In case of doubt, consult
your doctor or pharmacist.
The following information refers to the dosing of Amantix unless otherwise instructed by the physician.
Follow the administration instructions carefully; otherwise, Amantix may not work properly.
Duration of treatment
The tablets should be taken orally with a small amount of liquid, preferably in the morning and in the afternoon.
The last daily dose should not be taken later than 4 p.m.
Do not discontinue taking the tablets without consulting your doctor. The duration of treatment is determined by the
physician according to the patient's condition and individual response to therapy.
Dosage
Treatment of patients with parkinsonian syndromes and drug-induced movement disorders is usually initiated gradually.
The required dose and duration of treatment depend on the type and severity of symptoms and are determined by the physician.
Treatment is initiated by taking 1 tablet of Amantix once daily for the first 4 to 7 days (corresponding to 100 mg of amantadine sulfate per day).
The daily dose is then increased by 100 mg at weekly intervals until the maintenance dose is reached.
The usual maintenance dose is 1 to 3 tablets twice daily (corresponding to 200–600 mg of amantadine sulfate per day).
The daily dose may be divided into three doses, as determined by the physician.
In elderly patients, especially those with agitation, confusion, or symptoms of delirium, treatment should be initiated with a lower dose.
If the patient is concurrently taking other anti-parkinsonian medications, the physician will determine the appropriate dose of Amantix individually.
If the patient has previously been treated with amantadine administered as an infusion solution, the physician may use a higher initial dose.
The physician may use amantadine as an infusion solution in cases of acute worsening of Parkinson’s disease symptoms (akinetic crisis).
Patients with renal function impairment:
The dosage of Amantix tablets must be adjusted according to renal clearance (a parameter indicating kidney function).
The appropriate dose is determined by the physician.
Use in children and adolescents
There is no data available on the use of this medicine in children and adolescents.
Overdose of Amantix
In case of overdose, inform your doctor or ask a family member to inform the doctor and agree to be referred to hospital if severe poisoning occurs,
manifesting as nausea, vomiting, tremors or convulsions, unsteady gait, blurred vision, lethargy, depression, speech disturbances, or cardiac dysfunction.
When Amantix is taken together with other drugs used in Parkinson’s disease, states of confusion with hallucinations, even coma, and muscle twitching have been observed.
There is no known specific pharmacological treatment or antidote for Amantix overdose.
The physician may induce vomiting or perform gastric lavage.
Blood purification by dialysis (hemodialysis) is not recommended due to the low elimination of amantadine during dialysis (approximately 5%).
In life-threatening poisoning, intensive therapy is required. Therapeutic measures should include: fluid administration and acidification of urine to accelerate elimination of the toxic substance, sedation if possible, administration of anticonvulsant and antiarrhythmic drugs (intravenous lidocaine).
No specific antidote or drug is known.
In the treatment of neurotoxicity symptoms (as described above), intravenous physostigmine may be attempted at a dose of 1–2 mg every 2 hours in adults, and 2 × 0.5 mg with a 5–10 minute interval, up to a maximum dose of 2 mg in children.
The physician will perform an ECG and carefully monitor conditions favoring the development of cardiac arrhythmias, if necessary, e.g. electrolyte imbalance (hypokalemia or hypomagnesemia) or bradycardia.
Missed dose of Amantix
Do not take a double dose to make up for a missed dose.
Continue taking the single dose prescribed by your doctor.
Discontinuation of Amantix
Under no circumstances should treatment be stopped without consulting your doctor.
If the patient wishes to discontinue treatment, e.g. due to drug intolerance or worsening of disease symptoms, the physician should be informed.
Do not stop treatment abruptly, as this may lead to worsening of disease symptoms and withdrawal symptoms.
In patients with Parkinson’s disease, Amantix should not be discontinued suddenly, as this may lead to severe movement disorders, sometimes including immobility.
4. Possible adverse reactions
Like all medicines, this medicine can cause adverse reactions, although not everyone will experience them.
Possible adverse reactions of Amantix:
Common (occurring in more than 1 in 100 people but less than 1 in 10 people):
- sleep disturbances
- anxiety and agitation
- urinary retention in patients with benign prostatic hyperplasia (enlarged prostate)
- delusional (paranoid) symptoms (disturbances in perception and behavior), accompanied by visual hallucinations, mainly occurring in elderly patients; these adverse reactions occur more frequently in patients treated simultaneously with Amantix and other antiparkinsonian medicines (e.g. levodopa, bromocriptine) or memantine
- livedo reticularis (red-blue, net-like skin discoloration), sometimes accompanied by swelling of the lower legs and ankles
- nausea
- dizziness
- dry mouth
- sudden drop in blood pressure when standing up quickly from a lying or sitting position. This may cause dizziness or feeling faint (orthostatic hypotension).
Uncommon (affects less than 1 in 100 people):
- blurred vision
Rare (occurring in more than 1 in 10,000 people but less than 1 in 1,000 people):
- corneal damage, corneal edema, decreased visual acuity
Very rare (occurring in less than 1 in 10,000 people):
- leukopenia (reduced number of white blood cells) and thrombocytopenia (reduced number of platelets)
- cardiac disorders such as ventricular tachycardia, ventricular fibrillation, torsades de pointes, and QT interval prolongation; these disorders most commonly occur after exceeding the recommended doses or when amantadine is used concomitantly with other drugs having proarrhythmic effects, or in the presence of other risk factors for cardiac disorders (see section 2 "When not to take Amantix" and "Amantix with other medicines")
- transient loss of vision
- increased sensitivity to light
- seizures (usually after exceeding the recommended dose)
- muscle cramps
- sensory disturbances in limbs
Frequency not known (cannot be estimated from available data):
- irresistible urge to behave in an unusual manner – strong compulsion towards excessive gambling, disturbed or increased sexual drive, uncontrolled excessive shopping or spending, binge eating (consuming large amounts of food in a short time), or compulsive overeating (consuming more food than usual and more than needed to satisfy hunger)
If visual disturbances occur, such as loss of visual acuity or blurred vision, consult a physician to rule out corneal edema (see section 2).
Reporting of adverse reactions
If any adverse reactions occur, including any adverse reactions not listed in this leaflet, inform your doctor or pharmacist. Adverse reactions can be reported directly to the Department of Monitoring Adverse Drug Reactions at the Office for Registration of Medicinal Products, Medical Devices and Biocidal Products
Al. Jerozolimskie 181C, 02-222 Warsaw
Phone: +48 22 49 21 301
Fax: +48 22 49 21 309
Website: https://smz.ezdrowie.gov.pl
Reporting adverse reactions helps to provide more information on the safety of this medicine.
5. How to store the medicine Amantix
Keep the medicine out of sight and reach of children.
Do not use this medicine after the expiry date stated on the packaging. The expiry date refers to the last day of the month indicated.
Store below 25°C.
Translation of some information on the immediate packaging:
Batch No.:, Mfg. Dt. and Exp. Dt.: see stamp/No. de lote:, Fabr.: y Vto.: véase estampado – batch number, manufacturing date and expiry date: see imprint
Партида. N ., Годен до: вж. щампата – batch number and expiry date: see imprint
Medicines must not be disposed of via wastewater or household waste. Ask your pharmacist how to dispose of medicines no longer required. This will help protect the environment.
6. Contents of the pack and other information
What Amantix contains
The active substance in Amantix is amantadine sulfate.
Each coated tablet contains 100 mg of amantadine sulfate.
Excipients: monohydrate lactose, microcrystalline cellulose, potato starch, gelatin, povidone K 25,
talc, colloidal anhydrous silica, magnesium stearate, sodium carmellose.
Coating: talc, basic butyl methacrylate copolymer (Eudragit E), titanium dioxide (E 171),
magnesium stearate, orange yellow (E 110).
What Amantix looks like and contents of the pack
Amantix is an orange-coloured, round, film-coated tablet with a score line on one side. The score line is intended only to facilitate breaking the tablet for easier swallowing and does not ensure equal dosing.
The pack contains 30 or 100 film-coated tablets in a cardboard box.
For more detailed information, please contact the responsible entity or the parallel importer.
Marketing Authorisation Holder in Bulgaria, country of export:
Merz Pharmaceuticals GmbH
Eckenheimer Landstrasse 100
60318 Frankfurt am Main
Germany
Manufacturer:
Merz Pharmaceuticals GmbH
Eckenheimer Landstrasse 100
60318 Frankfurt am Main
Germany
Parallel importer:
Medezin Sp. z o.o.
ul. Zbąszyńska 3
91-342 Łódź
Poland
Repackaged by:
Medezin Sp. z o.o.
ul. Zbąszyńska 3
91-342 Łódź
Poland
Marketing Authorisation Number in Bulgaria, country of export: 9800025
Parallel Import Licence Number: 185/25
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| Brand name | Dosage form | Active substance / Dosage | Manufacturer |
|---|---|---|---|
| AMANTIX | tablets, film-coated |
|
Merz Pharmaceuticals GmbH |
| AMANTIX | tablets, film-coated |
|
Merz Pharmaceuticals GmbH |
| AMANTIX | tablets, film-coated |
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The original data is available in the language of the country of manufacture.
Data source: Register of Medicinal Products of Poland (URPL)
Data last verified: September 01, 2026