Prospect: information for the patient

Namuscla 167 mg hard capsules

mexiletine

Read this prospect carefully before starting to take this medicine, as it contains important information for you.

- Keep this prospect, as you may need to read it again.

- If you have any doubts, consult your doctor or pharmacist.

-This medicine has been prescribed only for you, and you must not give it to other people even if they have the same symptoms as you, as it may harm them.

-If you experience any adverse effects, consult your doctor or pharmacist, even if they are not listed in this prospect. See section 4.

There is aMedication Information Cardthat is distributed with Namuscla, to remind you and healthcare personnel of the risk of cardiac arrhythmias.Read the Medication Information Card along with this prospect and carry the card with you at all times.

1. What is Namuscla and what is it used for

2. What you need to know before starting to take Namuscla

3. How to take Namuscla

4. Possible adverse effects

5. Storage of Namuscla

6. Contents of the package and additional information

Namuscla is a medication that contains the active ingredient mexiletine.

Namuscla is used to treat the symptoms of myotonia (when muscles relax slowly and with difficulty after being used) in adults with non-dystrophic myotonic disorders, caused by genetic effects that affect muscle function.

Do not take Namuscla

-if you are allergic to mexiletine or any of the other components of this medication (listed in section 6)

- if you are allergic to any local anesthetic

- if you have had a heart attack

- if your heart does not function properly

- if you have certain heart rhythm disorders

- if your heart beats too quickly

- if you have damaged heart blood vessels

-if you are also taking certain medications to treat heart rhythm disorders (see Other Medications and Namuscla)

- if you are also taking certain medications with a narrow therapeutic margin (see Other Medications and Namuscla).

In case of doubt, ask your doctor or pharmacist.

Warnings and Precautions

Consult your doctor, pharmacist, or nurse before starting to take Namuscla if you have:

- heart problems

- liver problems

- kidney problems

- low or high potassium levels

- low magnesium levels

- epilepsy

Heart Function

Before starting treatment with Namuscla, you will have tests to check the functioning of your heart, including an ECG (electrocardiogram). These tests will also be performed periodically during treatment with Namuscla, and before and after any changes to your Namuscla dose. The frequency of these tests will depend on your heart function.

If you or your doctor detect any alteration in heart rhythm or any of the conditions listed in the "Do not take Namuscla" section, your doctor will suspend your treatment with Namuscla.

If you notice changes in your heart rhythm (if it beats faster or slower), if you experience fluttering or chest pain, if you have difficulty breathing, if you feel dizzy, if you sweat or faint,you must immediately contact an emergency center.

Some patients may have higher levels of Namuscla in the blood due to slower degradation in the liver, and it may be necessary to adjust the dose accordingly.

Children and Adolescents

Namuscla should not be used in children and adolescents under 18 years old.

Other Medications and Namuscla

Inform your doctor or pharmacist if you are using, have used recently, or may need to use any other medication.

Do not take Namuscla with certain medications for the treatment of heart rhythm disorders (quinidine, procainamide, disopyramide, ajmaline, encainide, flecainide, propafenone, moricizine, amiodarone, sotalol, ibutilide, dofetilide, dronedarone, vernakalant). See the "Do not take Namuscla" section. Taking Namuscla with any of these medications increases the risk of a serious heart rhythm disorder called torsades de pointes.

Do not take Namuscla with certain medications that have what is called a narrow therapeutic margin (medications in which small differences in dose or blood concentration can have an impact on the medication's effect or side effects). Examples of such medications include digoxin (for heart problems), lithium (mood stabilizer), phenytoin (for epilepsy), theophylline (for asthma), and warfarin (for blood clots).

Inform your doctor or pharmacist if you are using any of the following medications, as they may affect or be affected by Namuscla:

• medications for heart problems (lidocaine, tocainide, propranolol, esmolol, metoprolol, atenolol, carvedilol, bisoprolol, nebivolol, verapamil, diltiazem),
• other medications:

ortimolol for the treatment of glaucoma,

orcertain antibiotics (ciprofloxacin, rifampicin),

orsome antidepressants (fluvoxamine),

ortizanidine (used to relax muscles),

ormetformin (used for diabetes),

oromeprazole (for stomach ulcers and acid reflux).

Tobacco and Namuscla

Inform your doctor or pharmacist if you start or stop smoking while taking Namuscla, as smoking affects the levels of Namuscla in the blood and it may be necessary to adjust your dose accordingly.

Use of Namuscla with Beverages

It is recommended to reduce caffeine intake to half during treatment with mexiletine, as this medication can increase caffeine levels in the blood.

Pregnancy and Breastfeeding

If you are pregnant or breastfeeding, or if you think you may be pregnant, consult your doctor before using this medication. If you become pregnant while taking Namuscla, visit your doctor immediately, as it is preferable not to take Namuscla while pregnant. If you become pregnant while taking Namuscla, visit your doctor immediately.

Mexiletine passes into breast milk. You should discuss this with your doctor, and take a decision together about whether to abstain from breastfeeding or interrupt or abstain from receiving treatment with mexiletine.

Driving and Operating Machinery

Namuscla, in rare cases, may cause fatigue, confusion, and blurred vision: if you experience these effects, do not drive, ride a bike, or operate machinery.

Follow exactly the administration instructions for this medication as indicated by your doctor or pharmacist. If in doubt, consult your doctor or pharmacist again.

The recommended initial dose is 1 capsule per day. Your doctor will gradually increase the dose depending on how the medication is working. The maintenance dose is 1 to 3 capsules per day taken at regular intervals throughout the day.

Do not take more than 3 capsules per day.

Heart Function Check

Before starting treatment with Namuscla and regularly during treatment, you will have tests to check the functioning of your heart. Depending on how your heart is functioning, you may also need tests before and after any dose adjustment. See the "Warnings and Precautions" section. Your doctor will also regularly reevaluate your treatment to ensure that Namuscla remains the best medication for you.

Administration Form

Namuscla is for oral use.

Swallow the capsule with a glass of water while standing or sitting. You can take Namuscla with a meal to avoid stomach pain (see the "Possible Adverse Effects" section).

If you take more Namuscla than you should

If you have taken more Namuscla than the recommended dose, contact your doctor. It can be very harmful to your health. You or your partner should immediately contact your doctor if you feel numbness in your arms and legs, if you cannot think clearly or concentrate, if you have hallucinations or seizures, if you notice that your heart is beating slower, if you feel dizzy or faint, if you lose consciousness, or if your heart stops beating.

If you forgot to take Namuscla

If you have forgotten a dose, do not take a double dose and take the next one according to the usual schedule.

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

Like all medicines, this medicine may cause side effects, although not everyone will experience them.

The most serious side effects are:

Contact your doctor or go to the nearest emergency centerimmediatelyif you experience any of the following side effects:

- Severe allergy to mexiletine (with symptoms such as intense skin rash accompanied by fever); this is a very rare side effect, which may affect up to 1 in 10,000 people.

- Heart rhythm disorders, see in the section “Warnings and precautions” the symptoms and more information; this is a frequent side effect, which may affect up to 1 in 10 people.

Other side effects that may occur;

Frequent side effects (may affect more than 1 in 10 people):

- Abdominal pain (in the abdomen)

- Insomnia (difficulty sleeping)

Common side effects (affect up to 1 in 10 people):

- Drowsiness

- Headache

- Tingling in arms and legs

- Blurred vision

- Dizziness (sensation of loss of balance)

- Rapid heart rate

- Shortness of breath

- Low blood pressure (which may cause dizziness or feeling of fainting)

- Nausea

- Acne

- Pain in arms and legs

- Fatigue

- Weakness

- Chest discomfort

- General discomfort (sensation of general discomfort and illness)

- Convulsions (crises)

- Speech disorders

- Slow heart rate

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

- Abnormal liver function (observed after a blood test)

Very rare side effects (may affect up to 1 in 10,000 people):

- Liver damage, including inflammation (hepatitis)

- Intense reaction to the medicine (with skin rash and fever)

Unknown frequency (cannot be estimated from available data):

- Decreased white blood cell or platelet count

- Lupus syndrome (disease of the immune system)

- Redness and peeling of the skin

- Stevens-Johnson syndrome: intense allergic reaction with skin rash, often in the form of blisters and sores in the mouth and eyes and other mucous membranes

- Blisters on the skin, general discomfort, fever in the context of a condition called DRESS

- Hallucinations (seeing or hearing something that is not real)

- Transient confusion (temporary inability to think clearly or concentrate)

- Double vision

- Alteration of taste

- Heart rhythm disorders

- Loss of consciousness

- Palpitations

- Pulmonary fibrosis (lung disease)

- Diarrhea

- Vomiting

- Esophageal injury (tube that carries food)

Reporting side effects

If you experience side effects, consult your doctor or pharmacist, even if it is side effects that do not appear in this leaflet. You can also report them directly through the national notification system included in theAppendix V.By reporting side effects, you can contribute to providing more information on the safety of this medicine.

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

Do not use this medication after the expiration date that appears on the box and the blister pack after CAD. The expiration date is the last day of the month indicated.

Store below 30 °C. Store in the original packaging to protect it from moisture.

Medicines should not be disposed of through drains or in the trash. Ask your pharmacist how to dispose of the containers and medications that you no longer need. This will help protect the environment.

Composition of Namuscla

Each hard capsule contains:

- Hydrochloride of mexiletine corresponding to 166.62 mg of mexiletine (active principle)

-Other components (cornstarch, anhydrous colloidal silica, magnesium stearate, gelatin, iron oxide [E 172] and titanium dioxide [E 171]).

Appearance of Namuscla and contents of the container

Namuscla capsules are hard gelatin capsules of reddish color filled with white powder. Namuscla is available in blister packs containing 30, 50, 100 or 200 capsules.

Only some sizes of containers may be commercially marketed.

Marketing Authorization Holder

Lupin Europe GmbH

Hanauer Landstraße 139-143,

60314 Frankfurt am Main

Germany

Responsible for Manufacturing

Hormosan Pharma GmbH

Hanauer Landstraße 139-143,

60314 Frankfurt am Main

Germany

Lupin Healthcare (UK) Ltd

The Urban Building, second floor, 3-9 Albert Street

SL1 2BE Slough, Berkshire,

United Kingdom

Etablissement Pharmaceutique de l’AP-HP (Assistance Publique-Hôpitaux de Paris) AGEPS

11-13 rue Lavoisier,

92000 Nanterre, France

Etablissement Pharmaceutique de l’AP-HP (Assistance Publique-Hôpitaux de Paris) AGEPS

7 rue du Fer à Moulin,

75005 Paris, France

Last review date of this leaflet.

The detailed information on this medicine is available on the website of the European Medicines Agency:http://www.ema.europa.eu/.