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ATENZA 36 mg PROLONGED-RELEASE TABLETS

This page is for general information. Consult a doctor for personal advice. Call emergency services if symptoms are severe.
About the medicine

How to use ATENZA 36 mg PROLONGED-RELEASE TABLETS

Introduction

Package Leaflet: Information for the User

Atenza 18 mg prolonged-release tablets EFG

Atenza 27 mg prolonged-release tablets EFG

Atenza 36 mg prolonged-release tablets EFG

Atenza 45 mg prolonged-release tablets

Atenza 54 mg prolonged-release tablets EFG

methylphenidate, hydrochloride

Read the entire package leaflet carefully before you start taking, or giving your child, this medicine, as it contains important information for you.

  • Keep this package leaflet, as you may need to read it again.
  • If you have any further questions, ask your doctor or pharmacist.
  • This medicine has been prescribed for you only. Do not pass it on to others. It may harm them, even if their symptoms are the same as yours.
    • If you experience any side effects, talk to your doctor or pharmacist. This includes any possible side effects not listed in this package leaflet. See section 4.

Contents of the package leaflet

  1. What is Atenza and what is it used for
  2. What you need to know before you take Atenza
  3. How to take Atenza
  4. Possible side effects

5 Conservation of Atenza

  1. Contents of the pack and further information

1. What is Atenza and what is it used for

What is it used for

This medicine is used to treat “attention deficit hyperactivity disorder” (ADHD).

  • It is used in children from 6 years of age and in adults.
  • It is used only after non-medication treatments, such as behavioral therapy and counseling, have been tried.

This medicine is not indicated for the treatment of ADHD in children under 6 years of age.

How it works

This medicine improves the activity of certain parts of the brain that are underactive. The medicine may help improve attention (level of attention), concentration, and reduce impulsive behavior.

The medicine is given as part of a comprehensive treatment program, which usually includes:

  • psychological therapy
  • educational therapy and
  • social therapy.

It is only prescribed by doctors who have experience in behavioral problems in children, adolescents, or adults. If you are an adult and have not been treated before, the specialist will perform tests to confirm that you have had ADHD since childhood.

Although ADHD has no cure, it can be controlled using comprehensive treatment programs.

About ADHD

Children and adolescents with ADHD have difficulty:

  • staying still and
  • focusing.

It is not their fault that they cannot do these things.

Many children and adolescents struggle to do them. However, ADHD can cause problems in everyday life. Children and adolescents with ADHD may have difficulty learning and doing homework. They have difficulty behaving well at home, at school, and in other places.

ADHD does not affect intelligence.

Adults with ADHD often have difficulty concentrating. They often feel restless, impatient, and distracted. They may have difficulty organizing their private life and work.

Not all patients with ADHD need treatment with medication.

2. What you need to know before you take Atenza

Do not take Atenza if you:

  • are allergic to methylphenidate or any of the other ingredients of this medicine (listed in section 6)
  • have a thyroid problem
  • have high eye pressure (glaucoma)
  • have a tumor in the adrenal glands (pheochromocytoma)
  • have an eating disorder, loss of appetite, or do not want to eat, such as in “anorexia nervosa”
  • have very high blood pressure or narrowing of the blood vessels, which can cause arm and leg pain
  • have had heart problems - such as a heart attack, irregular heartbeat, chest pain, heart failure, heart disease, or a heart problem at birth
  • have had a problem with the blood vessels in the brain, such as a stroke, dilation or weakness of part of a blood vessel (aneurysm), narrowing or blockage of the blood vessels, or inflammation of the blood vessels (vasculitis)
  • are taking or have taken in the last 14 days a certain type of antidepressant (known as a monoamine oxidase inhibitor), see “Other medicines and Atenza”
  • have mental health problems such as:
  • a “psychopathic” or “borderline personality” disorder
  • abnormal thoughts or visions or a disease called “schizophrenia”
  • signs of a severe mood disorder such as:
    • suicidal thoughts
    • severe depression, feeling very sad, worthless, and desperate
    • mania, feeling exceptionally elated, more active than usual, and uninhibited.

Do not take methylphenidate if you have any of the above. If you are not sure, tell your doctor or pharmacist before you take methylphenidate. This is because methylphenidate can worsen these problems.

Warnings and precautions

Tell your doctor before you start taking this medicine if you:

  • have liver or kidney problems
  • have problems swallowing or swallowing whole tablets
  • have a narrowing or blockage in the digestive tract
  • have had seizures (attacks, convulsions, epilepsy) or any alteration in the electroencephalogram (EEG, a brain study)
  • have ever abused or been dependent on alcohol, prescription medications, or drugs
  • are a woman and have started your period (see below the section on “Pregnancy, breastfeeding, and fertility”)
  • have difficulty controlling repetitive movements of some parts of the body or repeated sounds and words
  • have high blood pressure
  • have a heart problem not included in the previous “Do not take” section
  • have a mental health problem not included in the previous “Do not take” section. Other mental health problems include:
  • mood changes (from being manic to being depressed, known as “bipolar disorder”)
  • feeling aggressive or hostile
  • seeing, hearing, or feeling things that are not there (hallucinations)
  • believing things that are not real (delusions)
  • feeling strangely suspicious (paranoia)
  • feeling agitated, anxious, or tense
  • feeling depressed or guilty.

Tell your doctor or pharmacist if you have any of the above before starting treatment. This is because methylphenidate can worsen these problems. Your doctor will want to monitor how the medications affect you.

During treatment, children and adolescents may unexpectedly experience prolonged erections. Erections can be painful and occur at any time. It is essential to contact your doctor immediately if the erection lasts more than 2 hours, especially if it is painful.

Checks that your doctor will make before you start treatment with Atenza

To decide if methylphenidate is the right medicine for you, your doctor will talk to you about:

  • the medications you are taking
  • if you have a family history of sudden unexplained death
  • other diseases that you or your family (such as heart problems) may have
  • how you are feeling, if you have mood swings, have strange thoughts, or have had such feelings in the past
  • if there have been cases of “tics” in your family (difficulty controlling repetitive movements of some parts of the body or repeated sounds and words)
  • possible behavioral or mental health problems that you or other family members have had. Your doctor will explain specifically if you are at risk of experiencing mood changes (from being manic to being depressed, known as “bipolar disorder”). They will check your mental health history and check if any family member has a history of suicide, bipolar disorder, or depression.

It is essential that you provide all the information you can. This will help your doctor decide if methylphenidate is the right medicine for you. Your doctor may decide that you or your child need other medical tests before starting this medicine. For adults who start taking this medicine, your doctor may refer you to a cardiologist.

Other medicines and Atenza

Tell your doctor if you are taking, have recently taken, or might take any other medicines.

Do not take methylphenidate if you:

  • are taking a medicine called a “monoamine oxidase inhibitor” (MAOI) used for depression or have taken an MAOI in the last 14 days. Taking an MAOI with methylphenidate can cause a sudden increase in blood pressure (see “Do not take Atenza”).

Tell your doctor or pharmacist if you are taking any of the following medicines for depression or anxiety:

  • tricyclic antidepressant
  • selective serotonin reuptake inhibitor (SSRI)
  • serotonin and noradrenaline reuptake inhibitor (SNRI).

Taking methylphenidate with these types of medicines can cause a potentially life-threatening increase in “serotonin” in the brain (serotonin syndrome), which can cause confusion or restlessness, sweating, chills, muscle spasms, or rapid heartbeat. If you experience these side effects, seek medical attention immediately.

If you are taking other medicines, methylphenidate may affect how they work or cause side effects. If you are taking any of the following medicines, consult your doctor or pharmacist before taking methylphenidate:

  • medicines for severe mental health problems
  • medicines for Parkinson's disease (such as levodopa)
  • medicines for epilepsy
  • medicines used to lower or increase blood pressure
  • some cough and cold remedies that contain medicines that can affect blood pressure. It is essential to consult your pharmacist when purchasing any of these medicines
  • medicines that thin the blood to prevent clots.

If you are unsure if any of the medicines you are taking are included in the list above, consult your doctor or pharmacist for advice before taking methylphenidate.

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

Before an operation

Tell your doctor if you are going to have an operation. You should not take methylphenidate on the day of the operation with certain types of anesthetics. This is because a sudden increase in blood pressure can occur during the procedure.

Drug tests

This medicine may give a positive result in drug tests, even in tests used in sports.

Atenza with alcohol

Do not drink alcohol while taking this medicine. Alcohol can worsen the side effects of this medicine. Remember that some foods and medicines contain alcohol.

Pregnancy, breastfeeding, and fertility

If you are pregnant or breastfeeding, think you may be pregnant, or plan to become pregnant, consult your doctor before using this medicine.

Available data do not suggest an increased risk of total congenital anomalies, although a small increase in the risk of cardiac malformations during use in the first three months of pregnancy could not be ruled out. Your doctor will provide more information about this risk. Consult your doctor or pharmacist before using methylphenidate if you:

  • are having sex. Your doctor will discuss contraception with you
  • are pregnant or think you may be pregnant. Your doctor will decide if you should take methylphenidate
  • are breastfeeding or plan to breastfeed. Methylphenidate passes into breast milk. Therefore, your doctor will decide if you or your daughter should breastfeed while using methylphenidate.

Driving and using machines

You or your child may experience dizziness, problems focusing, or blurred vision when taking methylphenidate. If this occurs, it may be dangerous to perform certain activities such as driving, operating machinery, riding a bicycle or horse, or climbing trees.

This medicine may affect your ability to drive. Do not drive while taking this medicine until you know how it affects you. You may be committing an offense if your ability to drive safely is affected.

Atenza contains lactose

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

Atenza contains sodium

This medicine contains less than 1 mmol of sodium (23 mg) per tablet; this is, essentially “sodium-free”.

3. How to take Atenza

How much to take

Follow your doctor's instructions exactly. If you are unsure, consult your doctor or pharmacist again.

Your doctor will usually start treatment with a low dose and increase the daily dose by 18 mg no more than once a week if necessary.

The goal should be the lowest effective dose for you. Your doctor will decide the maximum daily dose for you or your child.

You should take this medicine once a day in the morning with a glass of water.

The tablet should be swallowed whole and not chewed, broken, or crushed. The tablet can be taken with or without food.

The tablet does not dissolve completely after all the medicine has been released, and sometimes the tablet may appear in the stool. This is normal.

Use in children from 6 years of age

  • The recommended initial dose of Atenza is 18 mg once daily for children who are not currently taking methylphenidate or for children who are switching from another stimulant to methylphenidate.
  • The maximum daily dose is 54 mg.

Use in adults

For adults who have taken Atenza before:

  • If you have already taken Atenza as a child or adolescent, the same daily dose (mg/day) can be used; your doctor will regularly check if any adjustment is necessary.
  • Adult patients may need a higher daily dose, but the doctor will try to give you the lowest effective dose.

For adults who have not taken Atenza before:

  • The recommended initial dose is 18 mg per day.
  • The maximum daily dose is 72 mg in adults.

If you do not feel better after 1 month of treatment

If you do not feel better after 1 month of treatment, tell your doctor. They may decide if you need a different treatment.

Incorrect use of Atenza

If this medicine is not used correctly, it can cause abnormal behavior. This can also mean that you start to depend on the medicine. Tell your doctor if you have ever been dependent on alcohol, prescription medications, or drugs.

This medicine is only for you. Do not give this medicine to anyone else, even if they have similar symptoms.

If you take more Atenza than you should

If you take too many tablets, consult your doctor immediately or go to the emergency department of the nearest hospital. Tell them how many tablets you have taken. Medical treatment may be necessary.

You can also contact the Toxicology Information Service, Teléfono 91 5620420, indicating the medicine and the amount taken. It is recommended to take the packaging and the package leaflet of the medicine to the healthcare professional.

Signs of overdose may include: being sick, agitation, tremors, increased uncontrolled movements, muscle contractions, seizures (which can be followed by coma), feeling very happy, confusion, seeing, hearing, or feeling things that are not there (hallucinations), sweating, flushing, headache, high fever, changes in heart rate (slow, fast, or irregular), high blood pressure, dilated pupils, and dryness of the nose and mouth.

If you forget to take Atenza

Do not take a double dose to make up for forgotten doses. If you or your child forget a dose, wait until the next scheduled dose.

If you stop taking Atenza

If you suddenly stop taking this medicine, ADHD symptoms or unwanted effects such as depression may reappear. Your doctor may want to gradually reduce the amount of medicine you take each day before stopping it completely. Consult your doctor before stopping treatment with this medicine.

What your doctor will do while you or your child are on treatment

Your doctor will perform some tests

  • before you start treatment to ensure that this medicine is safe and beneficial
  • once treatment has started, at least every 6 months and even more often. They will also be performed when the dose is changed
  • these tests will include:
  • appetite control
  • height and weight measurement
  • blood pressure and heart rate measurement
  • evaluation if you have mood-related problems, mental state, or any other unusual feeling. Or if this has worsened while taking this medicine.

Long-term treatment

This medicine does not need to be taken indefinitely. If you take this medicine for more than a year, your doctor should interrupt treatment for a short period, such as during school holidays. This allows demonstrating if you still need the medicine.

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

4. Possible Adverse Effects

Like all medicines, this medicine can cause adverse effects, although not all people suffer from them. Although some people present adverse effects, most people are helped by methylphenidate. Your doctor will inform you about these adverse effects.

Some adverse effects can be serious. If you have any of the following adverse effects, go to your doctor immediately:

Frequent (may affect up to 1 in 10 people)

  • irregular heartbeats (palpitations)
  • changes or alterations in mood or personality changes.

Uncommon (may affect up to 1 in 100 people)

  • suicidal thoughts or feelings
  • seeing, feeling, or hearing things that are not real, symptoms of psychosis
  • uncontrolled speech and body movements (Tourette's syndrome)
  • allergy signs such as rash, itching, or hives on the skin, swelling of the face, lips, tongue, or other parts of the body, shortness of breath, difficulty or problems breathing.

Rare (may affect up to 1 in 1,000 people)

  • feeling exceptionally excited, more active than normal, and uninhibited (mania).

Very Rare (may affect up to 1 in 10,000 people)

  • heart attack
  • sudden death
  • suicidal intention
  • seizures (attacks, convulsions, epilepsy)
  • skin peeling or red purpuric spots
  • inflammation or blockage of the arteries in the brain
  • temporary paralysis or movement and vision problems, speech difficulties (these signs may be related to problems with blood vessels in the brain)
  • uncontrolled muscle spasms that affect the eyes, head, neck, body, and nervous system
  • decrease in the number of blood cells (red blood cells, white blood cells, and platelets) that can cause a higher risk of infections and easier bleeding and bruising
  • sudden increase in body temperature, very high blood pressure, and severe convulsions ("Neuroleptic Malignant Syndrome"). It is not entirely certain that this adverse effect is caused by methylphenidate or other medications taken in combination with methylphenidate.

Unknown frequency (frequency cannot be estimated from available data)

  • unwanted recurring thoughts
  • unexplained fainting, chest pain, shortness of breath (may be signs of heart problems)
  • prolonged erections, sometimes painful, or increased number of erections.

If you experience any of the above adverse effects, go to your doctor immediately.

The following are other adverse effects, and if they become severe, please inform your doctor or pharmacist:

Very common (may affect more than 1 in 10 people)

  • headache
  • feeling of nervousness
  • difficulty sleeping.

Frequent (may affect up to 1 in 10 people)

  • joint pain
  • blurred vision
  • tension headache
  • dry mouth, thirst
  • difficulty staying asleep
  • high temperature (fever)
  • decreased sexual desire
  • hair loss or decreased hair thickness
  • muscle tension, muscle cramps
  • loss of appetite or decreased appetite
  • inability to have or maintain an erection
  • itching, rash, or redness that itches (hives)
  • excessive drowsiness or sleepiness, feeling tired
  • excessive teeth grinding (bruxism)
  • panic feeling
  • tingling, itching, or numbness of the skin
  • increased levels of alanine aminotransferase in blood (liver enzyme)
  • cough, sore throat, and irritation of the throat or nose; upper respiratory tract infection, sinusitis
  • high blood pressure, rapid heartbeat (tachycardia)
  • dizziness (vertigo), feeling of weakness, uncontrolled movements, excessive activity
  • aggression, agitation, anxiety, depression, irritability, tension, nervousness, and abnormal behavior
  • stomach discomfort or indigestion, stomach pain, diarrhea, feeling nauseous, stomach upset, and vomiting
  • excessive sweating
  • weight loss.

Uncommon (may affect up to 1 in 100 people)

  • dry eyes
  • constipation
  • chest discomfort
  • blood in the urine
  • apathy
  • agitation or tremor
  • increased need to urinate
  • muscle pain, muscle twitches
  • shortness of breath or chest pain
  • feeling of heat
  • increased liver test results (seen in a blood test)
  • anger reaction (angry), restless, or tearful, excessive awareness of the environment, sleep problems.

Rare (may affect up to 1 in 1,000 people)

  • changes in sexual desire
  • feeling disoriented or confused
  • vision problems or double vision
  • breast swelling in men
  • excessive sweating, skin redness, increased skin rash redness.

Very Rare (may affect up to 1 in 10,000 people)

  • muscle cramps
  • small red spots on the skin
  • abnormal liver function, including sudden liver failure and coma
  • changes in test results, including liver and blood tests
  • abnormal thinking, absence of feelings or emotion, doing things over and over, obsession with something
  • fingers and toes numbness, tingling, and color change with cold (from white to blue to red) ("Raynaud's phenomenon").

Unknown frequency (frequency cannot be estimated from available data)

  • migraine
  • dilated pupils
  • very high fever
  • slow, fast, or irregular heartbeats
  • major epileptic seizure ("grand mal" convulsions)
  • believing things that are not true
  • severe stomach pain with feeling of discomfort and vomiting
  • problems with blood vessels in the brain (stroke, cerebral arteritis, or cerebral occlusion)
  • inability to control urine elimination (incontinence)
  • jaw muscle spasm that makes it difficult to open the mouth (trismus)
  • stuttering
  • nosebleed.

Effects on Growth

When used for more than a year, methylphenidate may reduce growth in some children. This affects less than 1 in 10 children.

  • may prevent weight or height increase
  • your doctor will carefully check your or your child's height and weight, as well as nutrition

Reporting of Adverse Effects

If you experience any type of adverse effect, consult your doctor, pharmacist, or nurse, even if it is a possible adverse effect that does not appear in this leaflet. You can also report them directly through the Spanish Pharmacovigilance System for Human Use Medicines: www.notificaRAM.es By reporting adverse effects, you can contribute to providing more information on the safety of this medicine.

5. Conservation of Atenza

Keep this medicine out of sight and reach of children.

Do not use this medicine after the expiration date shown on the label after CAD. The expiration date is the last day of the month indicated.

Keep the bottle perfectly closed to protect it from moisture.

This medicine does not require any special storage temperature

Medicines should not be thrown away through wastewater or household waste. Deposit the packaging and medicines you no longer need at the Sigre point in your usual pharmacy. Ask your pharmacist how to dispose of the packaging and medicines you no longer need. This way, you will help protect the environment.

6. Package Contents and Additional Information

Composition of Atenza

The active ingredient is methylphenidate hydrochloride

  • Each tablet contains 18 mg, 27 mg, 36 mg, 45 mg, or 54 mg of methylphenidate hydrochloride.

The other components are:

  • Core of the tablet: hypromellose, macrogol, succinic acid, magnesium stearate, sodium chloride, anhydrous colloidal silica, iron oxide black (E172).
  • Coating film: cellulose acetate, macrogol.
  • Transparent coating: hypromellose, macrogol, phosphoric acid (for pH adjustments)
  • Color coating: lactose, hypromellose, triacetin, titanium dioxide (E171), iron oxide yellow (E172) (18 mg), iron oxide red (E172) (18 mg, 27 mg, 54 mg), iron oxide black (E172) (27 mg), indigo carmine (E132) (45 mg).

Appearance of the Product and Package Contents

18 mg: film-coated tablets, round, biconvex, yellow, approximately 9 mm in diameter, with a small hole on one face of the tablet.

27 mg: film-coated tablets, round, biconvex, gray, approximately 9 mm in diameter, with a small hole on one face of the tablet.

36 mg: film-coated tablets, round, biconvex, white, approximately 10 mm in diameter, with a small hole on one face of the tablet.

45 mg: film-coated tablets, round, biconvex, blue, approximately 10 mm in diameter, with a small hole on one face of the tablet.

54 mg: film-coated tablets, round, biconvex, pink, approximately 10 mm in diameter, with a small hole on one face of the tablet.

This medicine is available in a plastic bottle containing 2 desiccant bags, with a child-resistant plastic closure. The desiccant bags are used to keep the tablets dry and should not be eaten.

The package sizes are: 30 tablets, 60 tablets (2x30), and 90 tablets (3x30).

Only some package sizes may be marketed.

Marketing Authorization Holder and Manufacturer

Marketing Authorization Holder

Exeltis Healthcare, S.L.

Miralcampo Avenue, 7.

Miralcampo Industrial Estate.

19200 Azuqueca de Henares. Guadalajara.

Spain.

Manufacturer

Laboratorios Liconsa, S.A

Miralcampo Avenue, 7.

Miralcampo Industrial Estate.

19200 Azuqueca de Henares.

Guadalajara, Spain.

This medicine is authorized in the Member States of the European Economic Area under the following names:

Sweden: Phenichem 18 mg; 27 mg; 36 mg; 45 mg; 54 mg prolonged-release tablets

Spain: Atenza 18 mg; 27 mg; 36 mg; 54 mg prolonged-release tablets EFG

Atenza 45 mg prolonged-release tablets

Poland: Atenza

Date of the last revision of this leaflet: May 2024

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

About the medicine

How much does ATENZA 36 mg PROLONGED-RELEASE TABLETS cost in Spain ( 2025)?

The average price of ATENZA 36 mg PROLONGED-RELEASE TABLETS in October, 2025 is around 20.01 EUR. Prices may vary depending on the region, pharmacy, and whether a prescription is required. Always check with a local pharmacy or online source for the most accurate information.

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