


Ask a doctor about a prescription for ISOSORBIDE MONONITRATE NORMON 20 mg TABLETS
Package Leaflet: Information for the User
Isosorbide Mononitrate NORMON 20 mg Tablets
Read all of this leaflet carefully before you start taking this medicine because it contains important information for you.
Contents of the pack:
Isosorbide Mononitrate Normon contains isosorbide mononitrate as the active ingredient, which belongs to a group of medicines known as nitrates that have vasodilatory properties of the coronary arteries of the heart (arteries that irrigate the heart muscle).
This medicine is indicated for the treatment and prevention of angina pectoris (chest pain and feeling of oppression in the chest that occurs when not enough blood reaches the heart).
Do not take Isosorbide Mononitrate Normon
Warnings and precautions
Other medicines and Isosorbide Mononitrate Normon
Tell your doctor or pharmacist if you are taking, or have recently taken, any other medicines, including those obtained without a prescription.
Due to the possibility of potentiation of the hypotensive effect (decrease in blood pressure), caution should be exercised when administering Isosorbide Mononitrate Normon with antihypertensive medicines (medicines that reduce high blood pressure, e.g., calcium antagonists, beta-blockers, diuretics, angiotensin-converting enzyme inhibitors), vasodilators, neuroleptic drugs (medicines for the treatment of mental illnesses) or tricyclic antidepressants (medicines for depression).
With alcohol, in addition to hypotension, the decrease in reaction capacity may be accentuated.
Nitrates can give false negatives (results that should be positive but are negative due to error) in cholesterol determination reactions in blood by the Zlatkis-Zak method.
Isosorbide Mononitrate Normon may increase the hypertensive effect of dihydroergotamine (medicine used for headache).
The concomitant administration of Isosorbide Mononitrate Normon with 5-phosphodiesterase inhibitors such as sildenafil (medicine used for erection disorders) may lead to life-threatening heart complications in sensitive individuals.
Taking Isosorbide Mononitrate Normon with food and drinks
Do not take this medicine with alcohol, as it potentiates the vasodilatory effect of isosorbide mononitrate, which may cause a rapid decrease in blood pressure.
The tablets should be taken after meals without chewing and with a large amount of liquid (a glass of water).
Pregnancy and breastfeeding
Consult your doctor or pharmacist before using any medicine.
Isosorbide Mononitrate Normon should not be taken during pregnancy, unless, in the strict opinion of the doctor, the benefit justifies the possible risks.
Isosorbide Mononitrate Normon should not be used during breastfeeding, as it is unknown whether it passes into breast milk.
Use in children
The use of Isosorbide Mononitrate Normon is not recommended in children because safety and efficacy have not been established in this population.
Driving and using machines
Do not drive, as Isosorbide Mononitrate Normon may prevent you from driving safely. This may be accentuated with alcohol consumption, when starting treatment, when starting a new comedication, or when changing from one medication to another.
Isosorbide Mononitrate Normon contains lactose
This medicine contains lactose. If your doctor has told you that you have an intolerance to certain sugars, consult with them before taking this medicine.
Use in athletes
Athletes are informed that this medicine contains a component that may result in a positive doping test.
Follow the administration instructions of Isosorbide Mononitrate Normon indicated by your doctor. Consult your doctor or pharmacist if you have doubts.
The normal dose of Isosorbide Mononitrate Normon is one 20 mg tablet two to three times a day.
The tablets should be taken after meals without chewing and with a large amount of liquid (a glass of water).
The tablets are scored and can be easily broken into two halves to allow for dose adjustment.
If the response obtained is not sufficient, the dose may be increased to 40 mg (two tablets) two or three times a day.
In patients not accustomed to treatment with nitrates, and to prevent or minimize possible headaches, during the start of treatment, your doctor will recommend starting with a low dose (e.g., half a tablet of Isosorbide Mononitrate Normon 20 mg, twice a day), which will be gradually increased later.
If you think the effect of Isosorbide Mononitrate Normon 20 mg tablets is too strong or too weak, tell your doctor or pharmacist.
During therapy with Isosorbide Mononitrate Normon, tolerance (decrease in effect) may develop. It is recommended to maintain the dose as low as possible and allow the maximum possible time interval between doses to recover sensitivity (first dose in the morning and last dose at the end of the afternoon).
It is convenient to take this medicine while sitting, especially at the beginning of treatment, if you are taking high doses or if you are over 65 years old.
It is important to start and stop treatment with Isosorbide Mononitrate Normon gradually and never abruptly. Your doctor will indicate the way to gradually increase and decrease the dose.
Your doctor will indicate the duration of your treatment with this medicine. Do not stop treatment before, as it could cause a sudden increase in blood pressure.
If you take more Isosorbide Mononitrate Normon than you should
If you have taken more Isosorbide Mononitrate Normon than you should, consult your doctor or pharmacist immediately.
The main symptoms in case of overdose are: headache, decrease in blood pressure with dizziness when standing up, tachycardia (increased heart rate) and cyanosis (bluish discoloration of the skin due to insufficient oxygenation of the blood).
It is recommended to keep the patient lying down with their legs elevated to correct the drop in blood pressure.
In case of overdose or accidental ingestion, consult your doctor or pharmacist immediately or call the Toxicology Information Service, phone 91 562 04 20, indicating the medicine and the amount ingested.
If you forget to take Isosorbide Mononitrate Normon
Do not take a double dose to make up for forgotten doses.
Take the tablet at the time you remember that day and continue with the usual dose.
Like all medicines, Isosorbide Mononitrate Normon can have side effects, although not everyone gets them.
During the use of Isosorbide Mononitrate Normon, the following side effects have been observed, whose frequency could not be established with precision.
In certain cases, especially with high doses, or at the beginning of treatment, orthostatic hypotension (dizziness when standing up) may occur. In particularly sensitive patients, hypotension may lead to syncope (fainting), which could be confused with the symptoms of a heart attack.
Occasionally, and especially when used for the first time, gastrointestinal disorders, such as nausea and/or vomiting, may appear.
In patients with a history of coronary artery disease (narrowing of the arteries that reach the heart), ischemia (transient or permanent decrease in blood flow) may occur.
In patients with methemoglobin reductase deficiency or abnormal hemoglobin structure, a blood disorder (methemoglobin formation) may occur, resulting in lower oxygen content in the blood, which may cause bluish discoloration of the skin and mucous membranes, headache, fatigue, difficulty breathing, and lack of energy.
Rarely, it may cause skin rashes and/or exfoliative dermatitis (peeling of the skin).
Other side effects are: headache, flushing or feeling of facial heat, dizziness, palpitations, fatigue. Generally, all these effects, including hypotension, disappear when continuing treatment or, in any case, when decreasing the dose.
If you think any of the side effects you are suffering from is serious or if you notice any side effect not mentioned in this leaflet, tell your doctor or pharmacist.
Keep out of sight and reach of children.
No special storage conditions are required.
Do not use Isosorbide Mononitrate Normon after the expiration date that appears on the packaging after "CAD.". The expiration date is the last day of the month indicated.
Medicines should not be disposed of via wastewater or household waste. Place the packaging and medicines you no longer need in the SIGRE collection point of your usual pharmacy. Ask your pharmacist how to dispose of the packaging and medicines you no longer need. This will help protect the environment.
Composition of Isosorbide Mononitrate Normon
Appearance of the product and packaging content
Isosorbide Mononitrate Normon 20 mg tablets are presented in the form of white or slightly creamy, flat, round, scored, and serigraphed tablets.
Isosorbide Mononitrate Normon 20 mg tablets are presented in packages of 40 and 80 tablets.
Marketing authorization holder and manufacturer
Laboratorios Normon, S.A.
Ronda de Valdecarrizo, 6
(SPAIN)
Other presentations
Isosorbide Mononitrate Normon 40 mg tablets
This leaflet was approved in February 2022
Detailed and updated information on this medicine is available on the website of the Spanish Agency for Medicines and Health Products (AEMPS) http://www.aemps.es/
The average price of ISOSORBIDE MONONITRATE NORMON 20 mg TABLETS in October, 2025 is around 2.5 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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