Patient Information Leaflet

Arechin, 250 mg, tablets
Chloroquini phosphas
Please read this leaflet carefully before using the medicine, as it contains
important information for the patient.

Keep this leaflet for future reference.
If you have any questions, consult your doctor, pharmacist, or nurse.
This medicine has been prescribed for a specific individual. Do not share it with others. The medicine may harm others, even if their symptoms are the same.
If you experience any adverse reactions, including those not listed in this leaflet, inform your doctor, pharmacist, or nurse. See section 4.

Table of Contents

What Arechin is and what it is used for
Important information before taking Arechin
How to take Arechin
Possible side effects
How to store Arechin
Contents of the pack and other information

1. What Arechin is and what it is used for

Arechin is an antimalarial medicine. The active substance is chloroquine phosphate, which acts against protozoa causing malaria, such as Plasmodium vivax, P. malariae, P. ovale, and certain strains of P. falciparum. The medicine is also effective against the amoeba causing amoebic dysentery (Entamoeba histolytica). Arechin has anti-inflammatory properties, although the mechanism is not fully understood.

Indications

Malaria: prevention and treatment of acute attacks, as well as suppressive treatment of malaria caused by Plasmodium vivax, Plasmodium malariae, Plasmodium ovale, and chloroquine-sensitive strains of Plasmodium falciparum.
Intestinal and extraintestinal amoebiasis, including hepatic abscess caused by Entamoeba histolytica, usually in combination with luminal amoebicides.
Various forms of lupus erythematosus, including systemic lupus erythematosus (SLE), chronic and discoid lupus erythematosus (DLE).
Rheumatoid arthritis.

2. Information before using Arechin

When not to use Arechin:

if the patient is allergic to chloroquine phosphate, 4-aminoquinoline derivatives, or any of the other ingredients of this medicine (listed in section 6);
if the patient has retinal changes or visual field disturbances caused by 4-aminoquinoline derivatives;
if the patient is taking amiodarone (a medicine used to treat irregular heartbeat).

Warnings and precautions
Before starting treatment with Arechin, discuss this with your doctor. You should consult your doctor, even if the warnings below refer to conditions that occurred in the past.
Exercise caution when using chloroquine in the patient groups described below.

Patients with retinal function disorders (except during the treatment of acute malaria); regular ophthalmological examinations should be performed every 3 months during prolonged use due to the risk of retinal damage (retinopathy). If abnormalities are detected, treatment must be stopped immediately.
Patients with blood abnormalities; blood tests should be monitored regularly in patients receiving long-term chloroquine therapy. If abnormalities unrelated to the underlying disease occur, treatment should be discontinued.
Patients with glucose-6-phosphate dehydrogenase deficiency (G6PD deficiency) (chloroquine may damage red blood cells in these patients).
Patients with severe gastrointestinal disorders.
Patients with a history of epilepsy or those taking anticonvulsant medications (seizures may occur after chloroquine administration).
Patients with psoriasis (skin disease), porphyria, or myasthenia gravis (chloroquine may exacerbate these conditions).

In all patients undergoing long-term treatment, neurological examinations should be performed every 3–6 months to detect early signs of muscle weakness. If abnormalities are observed, the medicine should be discontinued.
During prolonged treatment, exposure to sunlight and UV radiation should be avoided.
Chloroquine may lower blood glucose levels. Ask your doctor about symptoms associated with low blood glucose. Monitoring of blood glucose levels may be necessary.
Chloroquine may cause heart rhythm disturbances in some patients.
Patients with congenital or acquired QT interval prolongation (visible on ECG – electrocardiogram), known risk factors, existing heart rhythm disorders or a history of myocardial infarction, and those with electrolyte imbalances in the blood (especially low potassium or magnesium levels), should exercise caution when using chloroquine.
If palpitations or irregular heartbeat occur during chloroquine treatment, treatment must be stopped immediately, an ECG should be performed, and the doctor should be informed.
Cardiomyopathy, which may lead to heart failure and sometimes result in death, may occur in patients treated with chloroquine. In case of symptoms of cardiomyopathy (irregular heartbeat, shortness of breath, swelling of the lower limbs, excessive fatigue, fainting), seek immediate medical attention.
The risk of heart problems may increase with higher doses. Therefore, the dose prescribed by the doctor must be strictly followed.
Psychiatric symptoms such as irrational thoughts, hallucinations, disorientation, aggression, paranoia, feelings of depression, or emergence of self-harming or suicidal thoughts may occur in some individuals treated with Arechin, even in those who have never experienced such problems before. If the patient or someone close to them notices such adverse effects (see section 4), medical help should be sought immediately.

Children and adolescents
This medicine is not intended for use in children under 14 years of age.

Arechin and other medicines
Inform your doctor about all medicines currently used, recently taken, or planned for use.
Chloroquine should be used cautiously in patients taking medicines that affect heart rhythm. These include antiarrhythmic drugs, antidepressants (tricyclic antidepressants), antipsychotics, and certain antimicrobial agents (e.g. macrolide antibiotics such as azithromycin).
Concomitant use of chloroquine and amiodarone (a medicine used to control heart rhythm) is contraindicated.
Halofantrine should not be used simultaneously with chloroquine.
Chloroquine may increase blood levels of cyclosporine (a medicine mainly used after organ transplants).
During antimalarial treatment, rabies vaccination should not be administered, as it may reduce vaccine effectiveness. Rabies vaccination should be given before starting antimalarial treatment.
Concomitant use of penicillamine (a medicine mainly used in metal poisoning) with chloroquine may increase penicillamine blood levels, increasing the risk of severe adverse effects affecting the blood-forming system and/or kidneys, as well as allergic skin reactions.
Chloroquine significantly reduces the concentration of primaquine (an antiparasitic medicine).
Antacids (containing aluminium, calcium, or magnesium salts) reduce the absorption of chloroquine. A gap of approximately 2 hours should be maintained between taking chloroquine and any of these medicines.
Cimetidine (a medicine used for stomach disorders) increases chloroquine plasma concentration.
Concomitant use of chloroquine or hydroxychloroquine with amiodarone (a medicine used for heart rhythm disorders) is contraindicated due to increased risk of cardiac arrhythmias.
Hydroxychloroquine, and probably chloroquine, increases blood levels of digoxin (a medicine used for heart conditions).
Concomitant use of chloroquine and mefloquine (a medicine used for malaria prevention) increases the risk of seizures.
Chloroquine may potentially worsen symptoms of myasthenia gravis (a chronic disease characterized by rapid muscle fatigue and weakness) and thereby reduce the effectiveness of neostigmine and pyridostigmine.

Arechin with food and drink
Tablets should be taken after meals.

Pregnancy, breastfeeding, and fertility
If the patient is pregnant or breastfeeding, suspects she may be pregnant, or is planning to have a child, she should consult her doctor before using this medicine.
This medicine should not be used during pregnancy unless, in the opinion of the doctor, the potential benefit to the mother outweighs the risk to the fetus.
Chloroquine passes into breast milk. For malaria prevention, the medicine may only be used if prescribed by a doctor.
Breastfeeding should be avoided during long-term use of high-dose chloroquine for rheumatic diseases.

Use of Arechin in patients with kidney and/or liver impairment
The medicine should be used with caution in patients with impaired liver function (especially in acute alcoholic liver damage), in patients with alcohol-related diseases, and in patients with kidney disorders. Chloroquine should not be used for malaria prevention in patients with end-stage renal failure.

Use of Arechin in elderly patients
No special dosage adjustment is required in elderly patients.

Driving and operating machinery
Chloroquine may affect the ability to drive and operate machinery. Therefore, caution should be exercised when performing activities requiring mental and physical alertness during treatment.

3. How to use Arechin

This medicine should always be used exactly as directed by the physician. In case of doubt, consult
your doctor, pharmacist, or nurse.
Malaria
Prophylactic use
Orally, one week before travel to an endemic area, during the stay in the endemic area, and for
4 weeks after return: 1 dose per week, 2 tablets (500 mg) on the same day each week.
Treatment (malaria attack)
Plasmodium vivax and Plasmodium ovale infection

Day 1: initial dose 4 tablets (1000 mg), then 2 tablets (500 mg) after 6 hours
Day 2: 2 tablets (500 mg)
Day 3: 2 tablets (500 mg)

Plasmodium falciparum and Plasmodium malariae infection

Day 1: initial dose 4 tablets (1000 mg), then 2 tablets (500 mg) after 6–8 hours
Day 2: 2 tablets (500 mg)
Day 3: 2 tablets (500 mg)

Amebiasis and hepatic abscess
For 2 days: 2 tablets (500 mg) twice daily, i.e. 4 tablets (1000 mg) per day; then
for 2 to 3 weeks: 1 tablet (250 mg) twice daily, i.e. 2 tablets (500 mg) per day.
Dosage may be reduced or increased if necessary, and treatment may be repeated.
Systemic lupus erythematosus
Initially, 1 tablet (250 mg) twice daily for 1 to 2 weeks, followed by a maintenance dose, usually
1 tablet (250 mg) daily.
Rheumatoid arthritis
The usual dose is 1 tablet (250 mg) daily.
Improvement may require several weeks of treatment. Several months of therapy may be needed
to achieve maximum effect. If no improvement (i.e. reduction in joint swelling, improved mobility)
is observed after 6 months of treatment, the drug should be discontinued.
After discontinuation, disease relapse may occur. Reinitiation of chloroquine treatment is recommended
in such cases, provided there are no ophthalmological contraindications.
Patients with renal and/or hepatic impairment
Dosage of chloroquine should be adjusted in patients with renal impairment.
In malaria, dosage adjustment is not required in patients with creatinine clearance >50 ml/min or
10–50 ml/min.
When creatinine clearance is >10 ml/min, the dose should be reduced by 50%, i.e.:

Day 1: initial dose 2 tablets (500 mg), then 1 tablet (250 mg) after 6 hours
Day 2: 1 tablet (250 mg)
Day 3: 1 tablet (250 mg)

Use in children and adolescents
This medicine is intended for adults and adolescents over 14 years of age.
Tablets should not be divided.
Accidental overdose of Arechin
In case of accidental overdose, seek immediate medical advice from a doctor or pharmacist.
Chloroquine overdose is extremely dangerous and difficult to treat.
Symptoms of overdose include: nausea, vomiting, decreased arterial blood pressure, increasing
tinnitus, blurred and impaired vision, weakness, hemoglobinuria (excretion of free hemoglobin
in urine), oliguria, cardiac arrhythmias leading to irregular heartbeat, sudden cardiac arrest,
seizures, respiratory arrest, coma, severe allergic reactions characterized by swelling, erythema,
formation of blisters and bullae, laryngeal edema, fever, and dyspnea.
Overdose leading to circulatory failure, respiratory failure, and severe cardiac arrhythmias may
result in death.
After severe poisoning, the following may occur: QRS complex widening, bradyarrhythmias,
junctional rhythm, QT interval prolongation, atrioventricular block, ventricular tachycardia,
torsade de pointes, ventricular fibrillation.
After overdose, immediate medical attention is required. The stomach should be emptied promptly
and completely by inducing vomiting (only in conscious patients) or by gastric lavage.
Symptomatic treatment should be administered.
Activated charcoal administered via a gastric tube (after gastric lavage and within 30 minutes
of chloroquine ingestion) reduces absorption of the drug.
In cases of severe poisoning, intravenous infusions are used.
Missed dose of Arechin
Take the missed dose as soon as possible.
Do not take a double dose to make up for a missed dose.
Stopping the medication
If you have any further questions about the use of this medicine, consult your doctor, pharmacist,
or nurse.

4. Possible adverse reactions

Like all medicines, this medicine can cause adverse reactions, although not everyone will experience them.
You should contact your doctor immediately if any of the following adverse reactions occur:
difficulty breathing, swelling of the face, lips, tongue, throat, itchy rash or urticaria.

Very common (may affect more than 1 in 10 people): insomnia.
Common (may affect up to 1 in 10 people): depression.
Rare (may affect up to 1 in 1,000 people):

cardiomyopathy (heart muscle disease), which may lead to death when chloroquine is used long-term at high doses.
liver function disorders, hepatitis, abnormalities in liver function tests.
psychiatric disorders such as anxiety, restlessness, confusion, hallucinations, delirium.

Other adverse reactions of the medicine, for which the frequency is unknown (frequency cannot be
determined from available data):

irregular heart rhythm and life-threatening cardiac arrhythmias.
irregular heartbeat (changes in the recording of the heart's electrical activity – changes in electrocardiogram).
hypotension (low blood pressure).
anaemia, blood count abnormalities (agranulocytosis, decreased white blood cell count, thrombocytopenia, decreased neutrophil count), bone marrow suppression, haemolysis (breakdown of red blood cells) in patients with glucose-6-phosphate dehydrogenase deficiency.
feelings of depression or presence of self-harming or suicidal thoughts, anxiety states, feelings of disorientation, irrational thoughts, paranoia, aggression, sleep disturbances, restlessness, feelings of euphoria or excessive excitement, lack of concentration.
convulsions, epileptic seizures, mood changes and behavioural changes (psychoses, psychomotor agitation, manic episodes), headaches.
blurred vision, partial or complete loss of vision, accommodation disorders, double vision, changes in the retina (retinopathy) or cornea, visual field disturbances.
deafness (sensorineural), hearing loss in patients with pre-existing damage to the auditory organ, tinnitus.
gastrointestinal disturbances, loss of appetite, nausea, vomiting, diarrhoea, cramps.
greying of hair, alopecia, pruritus, urticaria, rash, skin pigmentation changes, mucous membrane and nail discoloration, allergic skin reactions, lichenoid skin changes, psoriasis flare-up, erythema multiforme, severe skin reactions (Stevens-Johnson syndrome), toxic epidermal necrolysis.
neuromyopathy and myopathy (muscle diseases, muscle weakness).
photosensitivity, allergic and anaphylactic reactions, including urticaria, angioedema.
decreased blood glucose levels.

In some individuals during treatment with Arechin other adverse reactions may occur.
Reporting of adverse reactions
If any adverse symptoms occur, including any adverse symptoms not listed
in this leaflet, you should inform your doctor, pharmacist, or nurse. 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
tel.: +48 22 49 21 301
fax: +48 22 49 21 309
Website: https://smz.ezdrowie.gov.pl
Adverse reactions can also be reported to the marketing authorisation holder.
Reporting adverse reactions helps to provide more information on the safety of the medicine.

5. How to store the medicine Arechin

Keep the medicine out of sight and reach of children.
Do not use the medicine Arechin after the expiry date stated on the packaging.
Store below 25°C. Keep in the original packaging to protect from light.
Medicines must not be disposed of via wastewater or household waste. Ask your pharmacist how to dispose of medicines no longer in use. This will help protect the environment.

6. Contents of the package and other information

What the medicine Arechin contains

The active substance is chloroquine phosphate.
One tablet contains 250 mg of chloroquine phosphate.
Other ingredients are: potato starch, gelatin, magnesium stearate, anhydrous colloidal silicon dioxide.

What Arechin looks like and contents of the pack
A white or almost white, round, biconvex tablet, with a "-" embossed on one side.
Each pack contains 30 tablets.
The tablets are packed in glass bottles with a label and patient leaflet, or in PVC/Al blisters containing 10 tablets each, placed in a cardboard box together with the patient leaflet.

Marketing Authorisation Holder
Adamed Pharma S.A.
Pieńków, ul. M. Adamkiewicza 6A
05-152 Czosnów
tel.: +48 22 732 77 00

Manufacturer
Adamed Pharma S.A.
Pieńków, ul. M. Adamkiewicza 6A
05-152 Czosnów