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THEO-DUR 300 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 THEO-DUR 300 mg PROLONGED-RELEASE TABLETS

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This page provides general information and does not replace a doctor’s consultation. Always consult a doctor before taking any medication. Seek urgent medical care if symptoms are severe.

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Introduction

Package Leaflet: Information for the User

THEO-DUR 300mg prolonged-release tablets

Theophylline

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

  • Keep this leaflet, 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 get any side effects, talk to your doctor or pharmacist. This includes any possible side effects not listed in this leaflet. See section 4.

Contents of the pack

  1. What Theo-Dur is and what it is used for
  2. What you need to know before you take Theo-Dur
  3. How to take Theo-Dur
  4. Possible side effects
  5. Storage of Theo-Dur
  6. Contents of the pack and other information

1. What Theo-Dur is and what it is used for

This medicine belongs to a group of medicines called bronchodilators, which means they dilate the bronchi and facilitate breathing.

It is indicated for the prevention and treatment of asthma or bronchial spasm associated with lung diseases such as chronic bronchitis or emphysema.

Doctor consultation

Not sure if this medicine is right for you?

Discuss your symptoms and treatment with a doctor online.

2. What you need to know before you take Theo-Dur

Do not take Theo-Dur

  • If you are allergic to the active substance or to any other medicine of the same group or to any of the other components of this medicine (listed in section 6).
  • If you have acute heart rhythm disorders (tachyarrhythmia).
  • If you have recently had a heart attack.

Warnings and precautions

Consult your doctor or pharmacist before taking Theo-Dur if:

  • You have any heart disease,
  • You have high blood pressure (hypertension),
  • You have an overactive thyroid gland (hyperthyroidism),
  • You have seizure disorders (epilepsy),
  • You have stomach ulcers (gastric and/or duodenal),
  • You have hemoglobin production deficiencies (porphyria),
  • You have liver and/or kidney problems (hepatic and/or renal insufficiency),
  • You know you do not properly eliminate theophylline.

Children

The use of theophylline is not recommended in children under one year of age.

Taking Theo-Dur with other medicines

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

Theophylline may decrease or increase the effect of other medicines, and in turn, the effect of theophylline may be decreased or increased by other medicines if taken together. For this reason, it is necessary that you inform your doctor if you are taking:

  • Other preparations containing theophylline or other xanthines (such as caffeine and similar substances),
  • Beta2 adrenergic receptor inducers (beta2-agonists, generally used to treat asthma),
  • Barbiturates, especially phenobarbital, pentobarbital, and primidone (used to produce sedation, relaxation),
  • Carbamazepine (anticonvulsant used for epilepsy),
  • Phenytoin and fosphenytoin (used for epilepsy),
  • Rifampicin and rifapentine (antibiotics),
  • Sulfinpyrazone (used to treat gout),
  • Products containing hypericum (St. John's Wort),
  • Oral contraceptives,
  • Macrolide antibiotics (especially erythromycin, troleandomycin, clarithromycin, josamycin, and spiramycin),
  • Quinolone antibiotics (gyrase inhibitors, especially ciprofloxacin, enoxacin, and pefloxacin; see below),
  • The antibiotic imipenem (especially central nervous system side effects such as seizures),
  • Isoniazid (treatment of tuberculosis),
  • Thiabendazole (treatment of fungi),
  • Calcium channel blockers (e.g., verapamil and diltiazem) used for heart diseases,
  • Propranolol (treatment of high blood pressure),
  • Mexiletine (treatment of heart problems),
  • Propafenone (treatment of heart problems),
  • Ticlopidine (prevention of blood coagulation),
  • Cimetidine, ranitidine, etintidine (preventing stomach acid production),
  • Allopurinol, febuxostat (treatment of gout),
  • Fluvoxamine (treatment of mental illnesses),
  • Interferon alfa and peginterferon alfa-2 (treatment of immunological disorders),
  • Zafirlukast (treatment of asthma),
  • Influenza vaccines,
  • Hydroxylamide (muscle treatments),
  • Zileuton (treatment of asthma),
  • Diuretics (furosemide),
  • Halothane (general anesthetic),
  • Digitalis (treatment of heart problems),
  • Benzodiazepines (used to produce sedation, relaxation).

If you are a smoker, tell your doctor as you may need to have your dose changed.

Interaction with diagnostic tests

If you are going to have any diagnostic tests (including blood tests, urine tests, skin tests using allergens), tell your doctor that you are taking this medicine as it may alter the results.

Taking Theo-Dur with food and drinks

High consumption of caffeine-containing beverages such as tea, coffee, cocoa, cola, and large amounts of chocolate should be avoided. These products can increase the side effects of this medicine.

Pregnancy and breastfeeding

If you are pregnant or breastfeeding, think you may be pregnant, or are planning to have a baby, ask your doctor for advice before taking this medicine.

Pregnancy

The use of theophylline is not recommended during pregnancy.

Breastfeeding

The use of theophylline is not recommended during breastfeeding.

Elderly

Do not use in people over 65 years old without consulting a doctor.

Driving and using machines

This type of medicine may affect your reaction speed, so you should be careful when driving and/or using machines, especially when starting treatment, changing the dose, or taking it with other medicines.

Theo-Dur contains lactose

If your doctor has told you that you have an intolerance to some sugars, consult with them before taking this medicine.

Theo-Dur contains sucrose

If your doctor has told you that you have an intolerance to some sugars, consult with them before taking this medicine.

3. How to take Theo-Dur

Follow exactly the administration instructions of this medicine given by your doctor or pharmacist. If you are unsure, consult your doctor or pharmacist again.

Your doctor will tell you the exact dose you should take. The doses will be taken at regular 12-hour intervals. It is important to strictly follow the dosage regimen, especially regarding the spacing of doses.

As a guideline, you can follow the dose below, but remember that the dose should be as recommended by your doctor.

Adults and adolescents over 16 years

The recommended dose for adults is 300 mg (1 tablet) every 12 hours. Your doctor may increase the dose depending on how you respond to treatment.

Pediatric population (between 1 and 16 years)

The recommended dose is 4 mg per kg of body weight per day. This amount will be divided into two doses every 12 hours.

Elderly patients

In the case of elderly patients, your doctor will assess the dose to be administered.

Method of administration

The tablets should be taken without dissolving, without chewing or biting, swallowing them with enough liquid.

It is recommended to take it at night, before going to bed.

If you take more Theo-Dur than you should

Consult your doctor or the nearest emergency service or call the Toxicology Information Service, Telephone 915 620 420, indicating the medicine and the amount taken. Bring the packaging and any remaining tablets with you.

If you forget to take Theo-Dur

Do not take a double dose to make up for forgotten doses. Take the next dose as your doctor has told you, at the usual time.

If you stop taking Theo-Dur

If you stop your treatment with Theo-Dur, your disease may worsen. Do not stop taking the medicine unless your doctor tells you to.

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

Medicine questions

Started taking the medicine and have questions?

Discuss your symptoms and treatment with a doctor online.

4. Possible side effects

Like all medicines, this medicine can cause side effects, although not everybody gets them.

The possible side effects are listed below:

  • Tachycardia and arrhythmia (changes in heartbeats), palpitations, blood pressure drop.
  • Gastrointestinal problems, nausea, vomiting, diarrhea, stomach problems (weakness of the lower esophageal sphincter tone) that can increase nocturnal esophageal reflux if you already have it.
  • Allergic reactions (hypersensitivity).
  • Blood disorders such as: potassium decrease (hypokalemia), calcium increase (hypercalcemia), sugar increase (hyperglycemia), creatinine increase, uric acid increase (hyperuricemia), and electrolyte changes.
  • Headache, excitement, tremor of limbs, nervousness, insomnia, seizures.
  • Increased urine production (diuresis).

Reporting of side effects

If you experience any side effects, talk to your doctor or pharmacist, even if it is possible side effects not listed in this leaflet. You can also report them directly through the Spanish Pharmacovigilance System for Human Use Medicines (website: www.notificaRAM.es).

By reporting side effects, you can help provide more information on the safety of this medicine.

5. Storage of Theo-Dur

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

No special storage conditions are required.

Do not use this medicine after the expiry date which is stated on the packaging after EXP. The expiry date is the last day of the month indicated.

Medicines should not be disposed of via wastewater or household waste. Ask your pharmacist how to dispose of medicines no longer required. These measures will help protect the environment.

6. Contents of the pack and other information

Composition of Theo-Dur

  • The active substance is theophylline. Each tablet contains 300 mg of anhydrous theophylline.
  • The other components are: acetoftalate of cellulose, cetyl alcohol, myristyl alcohol, white wax, diethyl phthalate, magnesium stearate, hydroxypropyl methylcellulose, anhydrous lactose, glycerol monostearate, neutral pellets (cornstarch and sugar spheres [sucrose and cornstarch]).

Appearance of the product and pack contents

Theo-Dur 300 mg prolonged-release tablets are presented in the form of white, cylindrical, scored tablets. The packs contain 40 tablets.

Marketing authorization holder and manufacturer

Marketing authorization holder

VEGAL FARMACEUTICA, S.L.

Vía de las Dos Castillas 9C, portal 2, 2º C

28224 Pozuelo de Alarcón – Madrid. Spain.

Manufacturer

GENERIS FARMACÊUTICA, S.A.

Rua Joäo de Deus, 19, Venda Nova, 2700-487 Amadora – Portugal

or

COVEX, S.A.

Calle Acero 25, Polígono Industrial Sur

28770 Colmenar Viejo - Madrid. Spain

Other presentations

Theo-Dur 100 mg prolonged-release tablets: Pack of 40 tablets.

Theo-Dur 200 mg prolonged-release tablets: Pack of 40 tablets.

Date of last revision of this leafletSeptember 2013

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.gob.es/

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When to consult Dr. Chekhun:

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Dr. Chekhun provides online consultations, where you can receive:

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Prescription and monitoring of medications must be carried out by your treating physician in an in-person (offline) setting. An online consultation does not replace a face-to-face visit but helps you make more informed decisions about your treatment.

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Tomasz Grzelewski

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Dr Tomasz Grzelewski is an MD, PhD specialist in allergy, paediatrics, general practice and sports medicine, with a clinical focus on dermatology, endocrinology, allergology and sports-related health. He has more than 20 years of clinical experience and completed his medical training at the Medical University of Łódź, where he defended his PhD thesis with distinction. His doctoral research was recognised by the Polish Society of Allergology for its innovative contribution to the field. Throughout his career, he has gained extensive expertise in diagnosing and managing a wide range of allergic and paediatric conditions, including modern allergen desensitisation techniques. For five years, Dr Grzelewski served as the Head of two paediatric departments in Poland, managing complex clinical cases and leading multidisciplinary teams. He also worked in medical centres in the United Kingdom, gaining experience across both primary care and specialist environments. With over a decade of telemedicine experience, he has provided online consultations across Europe and is valued for his clear, structured and evidence-based medical guidance. Dr Grzelewski is actively involved in clinical programmes focused on modern anti-allergic therapies. As a Principal Investigator, he leads research projects on sublingual and oral allergen desensitisation, supporting evidence-based progress in allergy treatment for both children and adults. In addition to his background in allergology and paediatrics, he completed dermatology studies through the Cambridge Education Group (Royal College of Physicians of Ireland) and a Clinical Endocrinology course at Harvard Medical School. This advanced training enhances his ability to manage skin manifestations of allergies, atopic conditions, urticaria, endocrine-related symptoms and complex immunological reactions. Patients commonly seek his care for: 

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Frequently Asked Questions

Is a prescription required for THEO-DUR 300 mg PROLONGED-RELEASE TABLETS?

THEO-DUR 300 mg PROLONGED-RELEASE TABLETS requires a prescription in Spain. You can check with a doctor online whether this medicine may be appropriate for your situation.

What is the active substance in THEO-DUR 300 mg PROLONGED-RELEASE TABLETS?

The active ingredient in THEO-DUR 300 mg PROLONGED-RELEASE TABLETS is theophylline. This information helps identify medicines with the same composition but different brand names.

How much does THEO-DUR 300 mg PROLONGED-RELEASE TABLETS cost in pharmacies?

The average pharmacy price for THEO-DUR 300 mg PROLONGED-RELEASE TABLETS is around 5.03 EUR. Prices may vary depending on the manufacturer and dosage form.

Who manufactures THEO-DUR 300 mg PROLONGED-RELEASE TABLETS?

THEO-DUR 300 mg PROLONGED-RELEASE TABLETS is manufactured by Vegal Farmaceutica S.L.. Pharmacy brands and packaging may differ depending on the distributor.

Which doctors can assess the use of THEO-DUR 300 mg PROLONGED-RELEASE TABLETS online?

Doctors such as Family doctors, Psychiatrists, Dermatologists, Cardiologists, Endocrinologists, Gastroenterologists, Pulmonologists, Nephrologists, Rheumatologists, Hematologists, Infectious disease physicians, Allergists, Geriatricians, Paediatricians, Oncologists may assess whether THEO-DUR 300 mg PROLONGED-RELEASE TABLETS is appropriate, depending on your situation and local regulations. You can book an online consultation to discuss your symptoms and possible next steps.

How to buy THEO-DUR 300 mg PROLONGED-RELEASE TABLETS in Spain?

Spain has a well-developed healthcare infrastructure across major cities such as Madrid, Barcelona, Valencia, and Seville. Pharmacies are widely available and operate under strict regulations, ensuring access to prescribed medications.

You can buy THEO-DUR 300 mg PROLONGED-RELEASE TABLETS in Madrid, Barcelona, Seville, or Valencia at any local pharmacy with a valid prescription.

To obtain a prescription, you can use Oladoctor:

What are the alternatives to THEO-DUR 300 mg PROLONGED-RELEASE TABLETS?

Other medicines with the same active substance (theophylline) include ELIXIFILIN 5.33 mg/ml ORAL SOLUTION, TEROMOL RETARD 300 mg PROLONGED-RELEASE TABLETS, THEO-DUR 100 mg PROLONGED-RELEASE TABLETS. These may have different brand names or formulations but contain the same therapeutic ingredient. Always consult a doctor before switching or starting a new medicine.

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