Allopurinol Kern Pharma 100 mg tablets EFG

Package leaflet: Information for the user

Introduction

Package leaflet: Information for the user

Alopurinol Kern Pharma 100 mg tablets EFG

Read the entire leaflet carefully before you start taking this medicine because it contains important information for you.

• Keep this leaflet as you may need to read it again.
• If you have any questions, consult your doctor or pharmacist.
• This medicine has been prescribed for you personally and must not be given to other people, even if they have the same symptoms as you, because it could harm them.
• If you experience any adverse effects, consult your doctor or pharmacist, even if they are effects not listed in this leaflet. See section 4.

In this leaflet:

1. What Alopurinol Kern Pharma is and what it is used for
2. What you need to know before taking Alopurinol Kern Pharma
3. How to take Alopurinol Kern Pharma
4. Possible side effects
5. How to store Alopurinol Kern Pharma
6. Contents of the pack and other information

1. What Alopurinol Kern Pharma is and what it is used for

Alopurinol belongs to a group of medicines called enzyme inhibitors, which work by controlling the rate at which a specific chemical process occurs in the body. In this case, the result is a reduction in the level of uric acid in plasma and urine.

Alopurinol is used to prevent the occurrence of gout and other conditions caused by excess uric acid in the body, such as kidney stones and certain types of renal or metabolic disorders.

2. What you need to know before starting to take Alopurinol Kern Pharma

Serious skin reactions (hypersensitivity syndrome, Stevens-Johnson syndrome, toxic epidermal necrolysis) have been reported with the use of allopurinol. Frequently, the rash may include ulcers in the mouth, throat, nose, genitals, and conjunctivitis (inflammation and redness of the eyes). These severe skin rashes are often preceded by flu-like symptoms such as fever, headache, and body aches. The rash may progress to blistering and widespread skin peeling. These serious skin reactions may be more common in people of Han Chinese, Thai, or Korean descent. In addition, having chronic renal failure may increase the risk in these patients. If you develop a skin rash or these skin symptoms, stop taking allopurinol and consult your doctor immediately.

Do not take Alopurinol Kern Pharma

• if you are allergic (hypersensitive) to allopurinol or to any of the other ingredients of Alopurinol Kern Pharma.

Take special care with Alopurinol Kern Pharma

• if you are experiencing an acute attack of gout.
• if you are pregnant, think you might be pregnant, or are breastfeeding.
• if you have or have had any kidney or liver disease.
• if you are taking or are about to start taking any medicine for heart conditions or high blood pressure.
• if you notice that you bruise more easily than before, or if you develop a sore throat or other signs of infection.
• if you develop a skin rash, skin peeling, blisters or sores in the lips or mouth, wheezing (whistling breathing), palpitations or chest tightness, or loss of consciousness: THESE SYMPTOMS MAY INDICATE THAT YOU ARE ALLERGIC to allopurinol. Stop treatment and contact your doctor immediately.

If you are unsure, consult your doctor.

You must stop treatment and contact your doctor as soon as possible if, while taking allopurinol, you experience any of the following symptoms:

• High fever.
• Joint pain or painful swelling in the groin, armpits, or neck.
• Jaundice (yellowing of the skin and eyes).
• Nausea or vomiting (which may be bloody).
• General feeling of being unwell.
• Weakness, numbness, or loss of consciousness.
• Headache, drowsiness, dizziness, vision disturbances.
• Chest pain, high blood pressure, or slow pulse.
• Swelling (edema) of the ankles.
• Increased thirst, fatigue, and weight loss.
• Appearance of boils.
• Blood in the urine.

Life-threatening skin rashes (Stevens-Johnson syndrome and toxic epidermal necrolysis) have been described with the use of allopurinol. These initially appear as red spots or circular patches, often with a central blister.

Other additional signs that may occur include sores in the mouth, throat, nose, genitals, and conjunctivitis (swollen and red eyes).

These potentially life-threatening skin rashes are often accompanied by flu-like symptoms. The rash may progress to widespread blistering or skin peeling.

The period of highest risk for developing severe skin reactions is during the first weeks of treatment.

If you have previously experienced Stevens-Johnson syndrome or toxic epidermal necrolysis with allopurinol, you must never use allopurinol again.

If you develop skin rashes or these skin symptoms, stop taking allopurinol, seek immediate medical attention, and inform the doctor that you are taking this medicine.

It is possible that starting treatment with allopurinol may trigger an acute attack of gout. Your doctor may recommend taking certain medications to prevent this. If a gout attack occurs, it is not necessary to discontinue treatment with Alopurinol Kern Pharma, provided that an appropriate anti-inflammatory medicine is used concurrently.

Taking other medicines

Inform your doctor or pharmacist if you are using or have recently used any other medicines, including those obtained without a prescription.

Especially the following:

• 6-mercaptopurine (for the treatment of autoimmune diseases) and azathioprine (to prevent transplant rejection and for the treatment of viral infections),
• vidarabine (adenine arabinoside, for the treatment of viral infections),
• salicylates (aspirin, for pain relief) and uricosuric agents (probenecid, for the treatment of gout),
• chlorpropamide (for the treatment of diabetes),
• theophylline (for asthma),
• phenytoin (for epilepsy),
• ampicillin (antibiotic),
• amoxicillin (antibiotic),
• cyclophosphamide (for rheumatoid arthritis and treatment of certain types of cancer),
• doxorubicin (for the treatment of certain types of lymphoma),
• bleomycin (for the treatment of certain types of cancer),
• procarbazine (for the treatment of certain types of cancer),
• mechlorethamine (for the treatment of certain types of cancer),
• cyclosporine (to prevent transplant rejection),
• coumarin anticoagulants (to prevent blood clots),
• didanosine (for the treatment of HIV).

The administration of 6-mercaptopurine or azathioprine together with allopurinol should be avoided. When 6-mercaptopurine or azathioprine are administered together with Alopurinol Kern Pharma, the dose of 6-mercaptopurine or azathioprine must be reduced because their activity will be prolonged. This could increase the risk of serious blood disorders. In this case, your doctor will closely monitor your blood count during treatment.

Seek immediate medical attention if you notice unexplained bruising, bleeding, fever, or sore throat.

When allopurinol is administered in combination with cytostatic agents (e.g., cyclophosphamide, doxorubicin, bleomycin, procarbazine, alkylating halides), blood dyscrasias occur more frequently than when these active substances are administered alone.

Therefore, periodic hematological monitoring should be performed.

If aluminum hydroxide is taken concomitantly, the effect of allopurinol may be reduced; therefore, an interval of at least 3 hours should be left between the administration of both medicines.

Pregnancy and breastfeeding

Allopurinol is not recommended if you are pregnant.

Allopurinol passes into breast milk. The use of allopurinol is not recommended during breastfeeding.

Consult your doctor or pharmacist before using any medicine.

Driving and using machines

Due to its side effects (drowsiness, dizziness, and impaired coordination), allopurinol may impair your ability to drive vehicles.

Do not drive or operate tools or machinery until you are reasonably certain that this medicine does not impair your capabilities.

Important information about some of the ingredients of Alopurinol Kern Pharma

This medicine contains lactose. If your doctor has informed you that you have an intolerance to certain sugars, consult him before taking this medicine.

3. How to take Alopurinol Kern Pharma

Follow exactly the dosing instructions for allopurinol provided by your doctor. Consult your doctor or pharmacist if you have any doubts.

For oral use only. Swallow the tablet whole with a little water. It is usually taken once daily, generally after a meal.

Your doctor will usually start treatment with a low dose of allopurinol (e.g., 100 mg/day) to reduce the risk of possible adverse effects. Your dose may be increased if necessary.

The usual dose is:

Adults:

The usual starting dose of allopurinol is 100 to 300 mg daily. The dose may be increased up to 900 mg per day, depending on your condition. In such cases, and if stomach discomfort occurs, it is recommended to divide the dose into several administrations per day and take it with food.

Children under 15 years of age:

The usual dose of this medicine in children is 100 mg to 400 mg daily.

Elderly patients:

Your doctor will recommend the lowest possible dose of allopurinol to reduce uric acid levels and control your symptoms.

Use in patients with impaired hepatic or renal function:

If you have liver or kidney problems, your doctor will prescribe the lowest effective dose of allopurinol to reduce uric acid levels and control your symptoms. In case of renal insufficiency, your doctor may advise taking less than 100 mg per day or taking 100 mg doses at intervals longer than one day.

If you are on dialysis two or three times a week, your doctor may prescribe a dose of 300–400 mg immediately after each dialysis session.

If you take more Alopurinol Kern Pharma than you should

In this case, contact the Toxicology Information Service. Telephone: 91 562 04 20, or consult your doctor.

In case of accidental ingestion of a large amount of medication, go immediately to your doctor or the nearest hospital emergency department. Take this leaflet with you.

If you forget to take Alopurinol Kern Pharma

If you miss a dose, take the next dose as soon as you remember. Then continue as usual. Do not take a double dose to make up for missed doses.

If you miss several doses, it is best to contact your doctor so they can decide what to do from that point onward.

If you stop treatment with Alopurinol Kern Pharma

Your doctor will indicate the duration of treatment with allopurinol. Do not stop treatment prematurely, even if you feel better.

If you have any further questions about the use of this medicine, ask your doctor or pharmacist.

4. Possible adverse effects

If you experience any of the following symptoms, stop taking the medicine and inform your doctor immediately:

Rare (affect fewer than 1 in 1,000 people):

• Fever and chills, headache, muscle pain (flu-like symptoms), and general malaise.
• Any changes in your skin, for example, mouth ulcers, throat, nose, genitals, and conjunctivitis (inflammation and redness of the eyes), blisters or widespread skin peeling.
• Severe hypersensitivity reactions, with fever, skin rash, joint pain, and abnormalities in blood tests and liver function tests (these may be symptoms of a multi-organ hypersensitivity disorder).

Like all medicines, Alopurinol Kern Pharma may have adverse effects, although not everyone experiences them.

The likelihood of these occurring is higher when there are kidney and/or liver impairments.

The frequency of adverse effects is classified as follows:

Very common (at least 1 in 10 patients)
Common (at least 1 in 100 patients)
Uncommon (at least 1 in 1,000 patients)
Rare (at least 1 in 10,000 patients)
Very rare (fewer than 1 in 10,000 patients)

Infections and infestations

Very rare: Infection of the hair follicle.

Blood and lymphatic system disorders

Very rare: Decrease in the number of white blood cells (increases the risk of infections), red blood cells (may cause tiredness, fatigue), platelets (cells involved in blood clotting, leading to bruising or bleeding more easily than usual).

Occasionally, allopurinol tablets may cause blood-related effects, manifesting as more frequent bruising than normal, sore throat, or other signs of infection. These effects usually occur in people with kidney or liver problems. Inform your doctor as soon as possible if you experience any of these symptoms.

Immune system disorders

Uncommon: Hypersensitivity reactions (allergy: possible appearance of skin rash, skin peeling, blisters or sores in the lips or mouth).

Rare: Severe hypersensitivity reactions, associated with skin exfoliation, fever, joint pain, or painful swelling of the groin, armpits, or neck, jaundice (yellowing of the skin and eyes), and other skin and subcutaneous tissue disorders (see below).

Very rare: Angioimmunoblastic lymphadenopathy (swelling in armpits, neck, groin).

Very rarely, seizures, wheezing (whistling breathing), palpitations, chest tightness, or loss of consciousness may occur.

Potentially life-threatening severe allergic reaction.

Metabolism and nutrition disorders

Very rare: Diabetes mellitus (high blood sugar levels), increased levels of lipids (fats) in blood, increased uric acid in blood.

Psychiatric disorders

Very rare: Depression.

Nervous system disorders

Very rare: Weakness, numbness or loss of consciousness, paralysis, uncoordinated movements, disturbance in normal sensation (neuropathy), drowsiness, headache, altered taste.

Frequency unknown: Aseptic meningitis (inflammation of the membranes surrounding the brain and spinal cord): symptoms include neck stiffness, headache, nausea, fever, or altered consciousness. If you experience any of these symptoms, seek urgent medical attention.

Eye disorders

Very rare: Cataracts, visual disturbances.

Ear and labyrinth disorders

Very rare: Vertigo.

Cardiac disorders

Very rare: Chest pain or slowed pulse.

Vascular disorders

Very rare: High blood pressure.

Gastrointestinal disorders

Uncommon: Nausea, vomiting, diarrhoea.

Very rare: Presence of blood in vomit, excess fat in stools, mouth infections, changes in bowel habits.

Hepatobiliary disorders

Uncommon: Asymptomatic increases in liver function tests.

Rare: Hepatitis.

Skin and subcutaneous tissue disorders

Common: Skin rash.

Very rare: Hives, drug-type skin eruptions, hair loss or discoloration. Severe allergic reaction causing swelling of the face or throat.

Skin rashes may occur that could be life-threatening (Stevens-Johnson syndrome, toxic epidermal necrolysis) (see section 2).

Frequency unknown: Lichenoid eruption (reddish-purple rash with itching or white-grey thread-like lines on mucous membranes).

Renal and urinary disorders

Very rare: Presence of blood in urine.

Reproductive system and breast disorders

Very rare: Male infertility, impotence, breast enlargement.

General disorders and administration site conditions

Very rare: Swelling (edema) of the ankles, general malaise, fatigue, fever.

Investigations

Common: Elevated levels of thyroid-stimulating hormone in blood.

Cases of fever with or without evident signs or symptoms of generalized hypersensitivity to allopurinol have been reported (see Immune system disorders).

Do not be alarmed by this list of adverse reactions, as it is possible that none of them will occur in your case.

If you consider any of the adverse effects you experience to be severe, or if you notice any adverse effect not mentioned in this leaflet, inform your doctor or pharmacist.

Reporting of adverse effects

If you experience any type of adverse effect, consult your doctor or pharmacist, even if it is a possible adverse effect not listed in this leaflet. You may also report them directly via the Spanish Pharmacovigilance System for Human Medicines: https://www.notificaram.es. By reporting adverse effects, you can help provide more information on the safety of this medicine.

5. Storage of Alopurinol Kern Pharma

This medicine does not require special storage conditions.

Keep this medicine out of the sight and reach of children.

Do not use Alopurinol Kern Pharma after the expiry date stated on the carton, following “EXP”. The expiry date is the last day of the month indicated.

Do not use Alopurinol Kern Pharma if you notice any visible signs of deterioration.

Medicines must not be disposed of via wastewater or household waste. Dispose of empty containers and unused medicines at the SIGRE collection point at your pharmacy. If in doubt, ask your pharmacist how to dispose of unused containers and medicines. This will help protect the environment.

6. Package contents and other information

Composition of Alopurinol Kern Pharma 100 mg tablets

• The active substance is allopurinol. Each tablet contains 100 mg of allopurinol.
• The other components are: monohydrate lactose, corn starch, povidone, and magnesium stearate.

Appearance of the medicine and contents of the pack

Alopurinol Kern Pharma 100 mg tablets are available in packs of 25 and 100 tablets.

The tablets are white, round, and biconvex.

Only certain pack sizes may be marketed.

Marketing Authorization Holder

Kern Pharma, S.L.

Venus, 72 - Pol. Ind. Colón II

08228 Terrassa - Barcelona

Spain

Manufacturer

FAES FARMA, S.A.

C/ Máximo Aguirre, 14,

48940 Lamaico-Leioa (Vizcaya)

FAES FARMA, S.A.

Parque Científico y Tecnológico de Bizkaia

Ibaizabal Bidea, Edificio 901

48160 Derio (Bizkaia)

Spain

or

Kern Pharma, S.L.

Venus, 72 - Pol. Ind. Colón II

08228 Terrassa - Barcelona

Spain

This leaflet was last reviewed in February 2025

Detailed and up-to-date information on this medicine is available on the website of the Spanish Agency for Medicines and Health Products (AEMPS) http://www.aemps.es/.