Background pattern
Alka-seltzer 2,1 g comprimidos efervescentes

Alka-seltzer 2,1 g comprimidos efervescentes

About the medicine

About the medication

Introduction

Label: information for the user

ALKA-SELTZER2,1 geffervescent tablets

Sodium hydrogen carbonate

Read this label carefully before starting to use this medication, as it contains important information for you.

Follow exactly the medication administration instructions contained in this label or those indicated by your doctor or pharmacist.

  • Keep this label, as you may need to refer to it again.
  • If you need advice or more information, consult your pharmacist.
  • If you experience any adverse effects, consult your doctor or pharmacist, even if they are not listed in this label. See section 4.
  • You should consult a doctor if your symptoms worsen or do not improve after 14 days.

1. What is Alka-Seltzer and what is it used for

It belongs to the group of medications called antacids that act by reducing excess stomach acidity.

This medicationis indicated for symptomatic relief of stomach acid and heartburn in adults and adolescents 12 years of age and older.

2. What you need to know before starting to take Alka-Seltzer

Do not take ALKA-SELTZER:

  • If you are allergic to sodium bicarbonate or any of the other components of this medication (listed in section 6).
  • If you have metabolic or respiratory alkalosis.
  • If you have hypocalcemia.
  • If you have hypochlorhydria.
  • If you have a tendency to form edemas (fluid retention).
  • If you have appendicitis or its symptoms (nausea, vomiting, cramps, abdominal pain).
  • If you have intestinal obstruction (partial or total blockage of the intestine that interrupts the passage of intestinal content).

Warnings and precautions:

Consult your doctor or pharmacist before starting to take Alka-Seltzer.

Like other antacids, this medication may mask the symptoms of a more serious stomach disease, so if symptoms persist or worsen after 14 days of treatment, you should consult your doctor.

Use this medication with caution in patients with hypertension (elevated blood pressure), patients with liver, kidney, and heart diseases, edema, hypopotasemia, hypocalcemia, and aldosteronism (a syndrome associated with increased secretion of aldosterone hormone by the adrenal gland), and in patients taking diuretics, as it may cause hypochloremic alkalosis.

The use of Alka-Seltzer at high doses or for prolonged periods may cause metabolic alkalosis.

Due to its citric acid content, use this medication with caution in patients with uric acid stones, as it may promote the formation of calcium stones.

Children and adolescents:

Do not administer this medication to children under 12 years old.

Taking Alka-Seltzer with other medications:

Inform your doctor or pharmacist if you are taking, have taken recently, or may need to take any other medication.

This is especially important in the case of:

  • ketoconazole (used to treat fungal infections)
  • quinolones, tetracyclines (especially doxycycline), acidic forms of sulfonamide, erythromycin, methenamine (different classes of antibiotics)
  • iron salts (medications used to prevent or treat anemia)
  • naproxen, salicylates (used to treat pain and fever)
  • valproic acid (used to treat epilepsy)
  • levodopa (used to treat Parkinson's disease)
  • amphetamine, dextroamphetamine, ephedrine (central nervous system stimulants)
  • antiarrhythmic cardiac medications
  • methadone (used to relieve intense pain)
  • mecamilamine (medication for hypertension)
  • lithium salts (used in some psychiatric diseases)
  • barbiturates
  • methotrexate (used to treat cancer and rheumatoid arthritis)
  • preparations containing calcium, as it may cause milk-alkali syndrome, whose symptoms are: hypercalcemia, kidney problems, heart problems, metabolic alkalosis, dizziness, vomiting, muscle cramps, apathy, headache, confusion, and anorexia.

Like other antacids, this medication, when taken with enteric-coated medications, may cause the coating to dissolve too quickly, leading to gastric or duodenal irritation.

Antacids modify the absorption of numerous medications, so, in general, their administration should be separated from any other medication.In general, this medication should be taken at least 2 hours before or after the administration of any other medication.

Inform your doctor or pharmacist if you are taking, or have taken recently, any other medication, including those acquired without a prescription.

Interference with diagnostic tests:

If you are to undergo any diagnostic test (including blood, urine, gastric acid secretion tests, etc.), inform your doctor that you are taking this medication, as it may alter the results.

Taking ALKA-SELTZER with food and beverages:

Do not take this medication with milk or dairy products.

Due to its sodium bicarbonate content, do not take this medication immediately after excessive food and drink, as it may cause an increase in carbon dioxide production, leading to gastric distension and, in rare cases, perforation of the stomach walls.

Pregnancy, lactation, and fertility:

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

Driving and operating machines:

No effects of Alka-Seltzer on the ability to drive and operate machines have been described.

Alka-Seltzer contains Sodium and Aspartame (E-951).

This medication contains 570 mg of sodium (main component of table salt/for cooking) in each effervescent tablet. This is equivalent to 28.5% of the maximum recommended daily sodium intake for an adult.

Consult your doctor or pharmacist if you need 6 or more effervescent tablets daily for a prolonged period, especially if you have been recommended a low-sodium diet.

This medication contains 10 mg of aspartame in each effervescent tablet. Aspartame contains a source of phenylalanine that may be harmful in cases of phenylketonuria (PKU), a rare genetic disease in which phenylalanine accumulates due to the body's inability to eliminate it correctly.

3. How to Take Alka-Seltzer

Follow exactly the administration instructions for this medication contained in this leaflet or those indicated by your doctor or pharmacist. In case of doubt, ask your doctor or pharmacist.

This medication is administered orally.

The recommended dose is:

Adults and adolescents 12 years and older: The usual dose is 1 effervescent tablet, if necessary increase to 2, after meals or when experiencing gastrointestinal discomfort.

Do not exceed 6 tablets per day.

Individuals 65 years and older: Do not exceed 3 tablets per day.

Patients with renal insufficiency

They must consult their doctor before taking this medication.

Use in children and adolescents

Do not use in children under 12 years

Always use the smallest effective dose.

If you estimate that the action of ALKA-SELTZER is too strong or too weak, inform your doctor or pharmacist.

This medication should not be taken with an excessively full stomach.Wait between 20 minutes and 1 hour after meals before taking the medication.It is necessary to wait always until the effervescent tablet has completely dissolved in water and the bubbling has stopped, before taking it. Consult your doctor if you observe strong stomach pain immediately after taking the medication.

The administration of this preparation is subject to the appearance of gastrointestinal discomfort. As these symptoms disappear, this medication should be discontinued.

If symptoms persist for more than 14 days or worsen, or if other symptoms appear, treatment should be interrupted and the doctor consulted.

If you take more ALKA-SELTZER than you should

The main symptoms of overdose are metabolic alkalosis (headache, dizziness, ringing in the ears, blurred vision, drowsiness, sweating, nausea, vomiting, occasionally diarrhea, hyperirritability, and tetany (muscle weakness)) and fluid retention.

In case of overdose or accidental ingestion, consult your doctor or pharmacist immediately or go to a medical center immediately or call the Toxicological Information Service, phone: 91 562 04 20, indicating the medication and the amount ingested.

If you forgot to take ALKA-SELTZER:

Do not take a double dose to compensate for the missed dose.

4. Possible Adverse Effects

Like all medications, Alka-Seltzer may produce adverse effects, although not everyone will experience them.

Adverse reactions are listed in decreasing order of severity within each frequency range.

The convention used for defining frequencies is as follows: very common (≥1/10); common (≥1/100 to <1

Unknown frequency (frequency cannot be estimated from available data):Flatulence (gas in the stomach or intestines), belching, vomiting, nausea, stomach distension, and rebound effect (increase in acidity produced by the medication itself).

Hypokalemia (decrease in potassium level in blood) and hypernatremia (increase in sodium level in blood).

Continuous use or high doses may produce systemic alkalosis, whose symptoms include difficulty breathing, muscle weakness, increased muscle tone, spasms, tetany (involuntary muscle contractions), especially with hypercalcemia, anxiety, and other effects on the central nervous system.

Hypertension (increase in blood pressure) and edema (fluid retention) with continuous use or high doses.

Unknown frequency, oral ingestion of sodium hydrogen carbonate has caused spontaneous gastric perforation due to gas production.

Excessive oral administration of medications containing citrate salts may have a laxative effect.

Reporting 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 prospectus. You can also report them directly through the Spanish System for Pharmacovigilance of Medicinal Products for Human Use: http://www.notificaram.es. By reporting adverse effects, you can contribute to providing more information on the safety of this medication

5. Conservation of Alka-Seltzer

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

Keep the container perfectly closed.

Do not use Alka-Seltzer after the expiration date that appears on the container, after the abbreviation CAD. The expiration date is the last day of the month indicated.

Medicines should not be thrown down the drain or in the trash. Dispose of the containers and medicines you no longer need at the SIGRE collection point of the pharmacy. If in doubt, ask your pharmacist how to dispose of the containers and medicines you no longer need. In this way, you will help protect the environment.

6. Contents of the packaging and additional information

Composition of Alka-Seltzer

  • The active ingredient is Sodium Hydrogen Carbonate. Each effervescent tablet contains2.1 g(2081.8 mg) of sodium hydrogen carbonate (sodium bicarbonate).
  • The other components (excipients) are citric acid, aspartame (E-951), mannitol (E-421), potassium acesulfame, lemon-lime flavor, vanilla flavor, and amiflex (a compound of amino acids, glutamic acid, and sodium chloride).

Appearance of the product and contents of the packaging:

This medication iseffervescent tablets, round, and white in color. They are presented in packaging of 10 or 20 effervescent tablets.

Some packaging sizes may not be marketed.

The holder of the marketing authorization

BAYER HISPANIA, S.L.

Av. Baix Llobregat, 3-5

08970 Sant Joan Despí (Barcelona)

Responsible for manufacturing:

BAYER BITTERFELD GmbH

OT Greppin

Salegaster Chaussee, 1

06803 Bitterfeld-Wolfen

Germany

Date of the last review of this leaflet: September 2019

The detailed and updated information on this medication is available on the website of the Spanish Agency for Medicines and Medical Devices (AEMPS)http://www.aemps.es/

Country of registration
Active substance
Prescription required
No
Composition
Aspartamo (e-951) (10 mg mg), Manitol (e-421) (335,50 mg mg), Acesulfamo potasico (2 mg mg)
This information is for reference only and does not constitute medical advice. Always consult a licensed doctor before taking any medication. Oladoctor is not responsible for medical decisions based on this content.

Talk to a doctor online

Have questions about this medication or your symptoms? Connect with a licensed doctor for guidance and personalized care.

5.01 review
Doctor

Anna Moret

Dermatology18 years of experience

Dr. Anna Moret is a board-certified dermatologist and dermatovenereologist. She specialises in adult and pediatric dermatology, venereology, aesthetic skin care, and general medicine. Her consultations are evidence-based and tailored to each patient’s dermatological needs.

Dr. Moret provides expert evaluation and treatment for: • Skin conditions such as eczema, acne, rosacea, dermatitis, and psoriasis • Hair and scalp issues including hair loss, dandruff, and seborrheic dermatitis • Pediatric skin problems — from newborns to adolescents • Sexually transmitted infections (STIs) and dermatovenereology • Aesthetic concerns: skin ageing, non-invasive cosmetic treatments • Skin allergies and hypersensitivity reactions • Mole checks, lesion evaluation, and skin cancer screening • Skincare advice and personalised cosmeceutical routines

Combining dermatology with general medical knowledge, Dr. Moret offers comprehensive care that addresses both skin health and underlying conditions. She also holds certification from the Canadian Board of Aesthetic Medicine, ensuring an internationally aligned approach to aesthetic dermatology.

CameraBook a video appointment
5.05 reviews
Doctor

Alina Tsurkan

Family medicine12 years of experience

Dr. Alina Tsurkan is a licensed family medicine physician based in Portugal, offering online consultations for adults and children. She provides professional primary care, with a focus on prevention, accurate diagnosis, and long-term management of acute and chronic conditions.

Dr. Tsurkan supports patients with a wide range of health issues, including: • Respiratory infections: cold, flu, bronchitis, pneumonia, and lingering coughs • ENT conditions: sinusitis, tonsillitis, otitis (ear infections), sore throat, allergic rhinitis • Eye conditions: allergic or infectious conjunctivitis, red eyes, irritation • Digestive issues: acid reflux (GERD), gastritis, irritable bowel syndrome (IBS), constipation, bloating, nausea • Urinary and reproductive health: urinary tract infections (UTIs), cystitis, prevention of recurrent infections • Chronic diseases: hypertension, diabetes, thyroid disorders, elevated cholesterol, weight management • Neurological complaints: headaches, migraines, sleep disturbances, fatigue, general weakness • Women’s health: menstrual irregularities, perimenopausal symptoms, preventive screening • Children’s health: fever, infections, digestive issues, follow-ups, vaccination guidance

She also provides: • IMT medical certificates for driving licence exchange in Portugal • Personalised preventive care and wellness consultations • Interpretation of test results and medical reports • Follow-up care and medication review • Support in managing multiple coexisting conditions • Remote prescription management and medical documentation

Dr. Tsurkan’s approach is evidence-based and holistic. She works closely with each patient to develop an individualised care plan that addresses both symptoms and root causes. Her goal is to empower patients to take control of their health and maintain well-being through lifestyle adjustments, routine check-ups, and early intervention.

CameraBook a video appointment
5.04 reviews
Doctor

Andrei Popov

General medicine6 years of experience

Dr. Andrei Popov is a licensed pain management specialist and general practitioner based in Spain. He provides expert online care for adults dealing with both chronic and acute pain, as well as a wide range of everyday health concerns.

He specialises in diagnosing and treating pain conditions that affect quality of life, including: • Chronic pain lasting more than 3 months • Migraines and recurring headaches • Neck, back, lower back, and joint pain • Post-traumatic pain following injury or surgery • Nerve-related pain, fibromyalgia, and neuralgia In addition to pain management, Dr. Popov helps patients with: • Respiratory infections (colds, bronchitis, pneumonia) • High blood pressure and metabolic conditions such as diabetes • Preventive care and routine health check-ups

Online consultations last up to 30 minutes and include a detailed symptom review, personalised treatment planning, and medical follow-up when needed.

Dr. Popov’s approach is rooted in evidence-based medicine, combined with individualised care tailored to each patient’s history, lifestyle, and clinical needs.

CameraBook a video appointment
5.03 reviews
Doctor

Yevgen Yakovenko

General surgery11 years of experience

Dr. Yevhenii Yakovenko is a licensed surgeon and general practitioner in Spain and Germany. He specialises in general, paediatric, and oncological surgery, internal medicine, and pain management. He offers online consultations for adults and children, combining surgical precision with therapeutic support. Dr Yakovenko works with patients across different countries and provides care in Ukrainian, Russian, English, and Spanish.

Areas of medical expertise: • Acute and chronic pain: headaches, muscle and joint pain, back pain, abdominal pain, postoperative pain. Identifying the cause, selecting treatment, and creating a care plan. • Internal medicine: heart, lungs, gastrointestinal tract, urinary system. Management of chronic conditions, symptom control, second opinions. • Pre- and postoperative care: risk assessment, decision-making support, follow-up after surgery, rehabilitation strategies. • General and paediatric surgery: hernias, appendicitis, congenital conditions, both planned and urgent surgeries. • Injuries and trauma: bruises, fractures, sprains, soft tissue damage, wound care, dressing, referral when in-person care is required. • Oncological surgery: diagnosis review, treatment planning, and long-term follow-up. • Imaging interpretation: analysis of ultrasound, CT, MRI, and X-ray results, surgical planning based on imaging data. • Second opinions and medical navigation: clarifying diagnoses, reviewing current treatment plans, helping patients choose the best course of action.

Experience and qualifications: • 12+ years of clinical experience in university hospitals in Germany and Spain • International education: Ukraine – Germany – Spain • Member of the German Society of Surgeons (BDC) • Certified in radiological diagnostics and robotic surgery • Active participant in international medical conferences and research

Dr Yakovenko explains complex topics in a clear, accessible way. He works collaboratively with patients to analyse health issues and make evidence-based decisions. His approach is grounded in clinical excellence, scientific accuracy, and respect for each individual.

If you are unsure about a diagnosis, preparing for surgery, or want to discuss your test results – Dr Yakovenko will help you evaluate your options and move forward with confidence.

CameraBook a video appointment
See all doctors

Stay informed and save on care

Get health tips, platform updates, and exclusive promos for subscribers.

Follow us on social media
FacebookInstagramTikTok