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

How to use ALKA-SELTZER 2.1 g EFFERVESCENT TABLETS

Introduction

Package Leaflet: Information for the User

ALKA-SELTZER2.1 gEffervescent Tablets

Sodium Hydrogen Carbonate

Read the package leaflet carefully before starting to use this medicine because it contains important information for you.

Follow the administration instructions of the medicine contained in this package leaflet or as indicated by your doctor or pharmacist.

Keep this package leaflet, as you may need to read it again.
If you need advice or more information, consult your pharmacist.
If you experience side effects, consult your doctor or pharmacist, even if it is a side effect not listed in this package leaflet. See section 4.
You should consult a doctor if it worsens or does not improve after 14 days.

Contents of the Package Leaflet:

What is Alka-Seltzer and what is it used for
What you need to know before taking Alka-Seltzer
How to take Alka-Seltzer
Possible side effects
Storage of Alka-Seltzer
Package Contents and Additional Information

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

It belongs to the group of medicines called antacids that work by reducing excess stomach acidity.

This medicine is indicated for the symptomatic relief of heartburn and stomach acid in adults and adolescents from 12 years old.

2. What you need to know before taking Alka-Seltzer

Do not take ALKA-SELTZER:

If you are allergic to sodium hydrogen carbonate or any of the other components of this medicine (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 edema (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 produces an interruption of the passage of intestinal contents through it).

Warnings and Precautions

Consult your doctor or pharmacist before taking Alka-Seltzer.

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

It is recommended to use this medicine with caution in patients with hypertension (high blood pressure), in patients with liver, kidney, and heart disease, edema, hypokalemia, hypocalcemia, and aldosteronism (syndrome associated with increased secretion of aldosterone by the adrenal gland) and in patients undergoing diuretic treatment as it may produce hypochloremic alkalosis.

Taking Alka-Seltzer at high doses or for prolonged periods could lead to metabolic alkalosis.

Due to its citric acid content, it is recommended to use with caution in patients with uric acid stones as it may favor the formation of calcium stones.

Children and Adolescents

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

Taking Alka-Seltzer with other medicines

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

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 (medicines 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)
amphetamines, dexamphetamine, ephedrine (central nervous system stimulants)
cardiac antiarrhythmics
methadone (used to relieve intense pain)
meCamylamine (medicine for hypertension)
lithium salts (used in some psychiatric illness)
barbiturates
methotrexate (used to treat cancer and rheumatoid arthritis)

preparations containing calcium, as it may develop the milk-alkali syndrome whose symptoms are: excess calcium in the blood, kidney problems, heart problems, metabolic alkalosis, dizziness, vomiting, muscle cramps, apathy, headache, confusion states, and anorexia.

As with other antacids, this medicine administered with enteric-coated medicines may cause the coating to dissolve too quickly, which can produce gastric or duodenal irritation.

Antacids modify the absorption of numerous medicines, so in general, their administration should be spaced out from any other medicine. In general, the intake of this medicine should be done at least 2 hours before or after the administration of any other medicine.

Tell your doctor or pharmacist if you are taking or have recently taken any other medicine, even those purchased without a prescription.

Interference with diagnostic tests:

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

Taking ALKA-SELTZER with food and drinks:

Do not take this medicine with milk or dairy products.

Due to its sodium hydrogen carbonate content, this medicine should not be taken immediately after excessive food or drink, as it may cause an increase in carbon dioxide production, which could lead to gastric distension and, in rare cases, may perforate the stomach walls.

Pregnancy, Breastfeeding, 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 medicine.

Driving and Using Machines:

No effect of Alka-Seltzer on the ability to drive and use machines has been described.

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

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

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

This medicine contains 10 mg of aspartame in each effervescent tablet. Aspartame contains a source of phenylalanine that may be harmful in case of phenylketonuria (PKU), a rare genetic disease in which phenylalanine accumulates because the body is unable to eliminate it properly.

3. How to take Alka-Seltzer

Follow the administration instructions of this medicine contained in this package leaflet or as indicated by your doctor or pharmacist. In case of doubt, ask your doctor or pharmacist.

This medicine is administered orally.

The recommended dose is:

Adults and adolescents from 12 years old: The usual dose is 1 effervescent tablet, if necessary increased to 2, after meals or when feeling gastric discomfort.

Do not exceed 6 tablets per day.

Elderly over 65 years: Do not exceed 3 tablets per day.

Patients with renal insufficiency

They should consult their doctor before taking this medicine.

Use in children and adolescents

Do not use in children under 12 years old.

Always use the lowest effective dose.

If you think the effect of ALKA-SELTZER is too strong or too weak, tell your doctor or pharmacist.

Do not take this medicine with a stomach excessively full of food or drink. You should wait between 20 minutes and 1 hour after meals before taking the medicine. It is necessary to wait until the effervescent tablet has completely dissolved in water and the bubbling has disappeared before taking it. Consult your doctor if you notice a strong stomach pain after taking the medicine.

The administration of this preparation is subject to the appearance of gastric discomfort. As they disappear, this medication should be suspended.

If the symptoms persist for more than 14 days or worsen or other symptoms appear, you should interrupt the treatment and consult your doctor.

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 Toxicology Information Service, phone: 91 562 04 20, indicating the medicine and the amount ingested.

If you forget to take ALKA-SELTZER:

Do not take a double dose to make up for forgotten doses.

4. Possible side effects

Like all medicines, Alka-Seltzer can cause side effects, although not everyone gets them.

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

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

Frequency not known (frequency cannot be estimated from available data):Flatulence (gas in the stomach or intestine), belching, vomiting, cramps, stomach distension, and rebound effect (increase in acidity produced by the medicine itself).

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

If used continuously or at high doses, it may produce systemic alkalosis, whose symptoms include difficulty breathing, muscle weakness, increased muscle tone, spasms, tetany (involuntary muscle contraction), especially with hypercalcemia, anxiety, and other effects on the central nervous system.

Hypertension (high blood pressure) and edema (fluid retention) if used continuously or at high doses.

With unknown frequency, oral ingestion of Sodium Hydrogen Carbonate has caused spontaneous gastric perforation due to gas production.

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

Reporting of side effects:

If you experience any side effect, consult your doctor or pharmacist, even if it is a possible side effect not listed in this package leaflet. You can also report them directly through the Spanish Medicines and Health Products Agency's website: http://www.notificaram.es. By reporting side effects, you can help provide more information on the safety of this medicine.

5. Storage of Alka-Seltzer

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

Keep the container tightly closed.

Do not use Alka-Seltzer after the expiration date stated on the container, after the abbreviation 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 containers and medicines you no longer need in the pharmacy's SIGRE collection point. If in doubt, ask your pharmacist how to dispose of containers and medicines you no longer need. This will help protect the environment.

6. Package Contents and Additional Information

Composition of Alka-Seltzer

The active ingredient is Sodium Hydrogen Carbonate. Each effervescent tablet contains 2.1 g (2081.8 mg) of sodium hydrogen carbonate (sodium bicarbonate).
The other ingredients (excipients) are citric acid, aspartame (E-951), mannitol (E-421), acesulfame potassium, lemon-lime flavor, vanilla flavor, and amiflex (a compound of amino acids, glutamic acid, and sodium chloride).

Appearance of the product and package contents:

This medicine is effervescent tablets, round and white in color. They are available in containers of 10 or 20 effervescent tablets.

Some container sizes may not be marketed.

Marketing Authorization Holder

BAYER HISPANIA, S.L.

Av. Baix Llobregat, 3-5

08970 Sant Joan Despí (Barcelona)

Manufacturer:

BAYER BITTERFELD GmbH

OT Greppin

Salegaster Chaussee, 1

06803 Bitterfeld-Wolfen

Germany

Date of the last revision of this package leaflet: September 2019

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/

Dr. Yevgen 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.
Obesity treatment and weight management: a medical approach to weight loss, including assessment of underlying causes, evaluation of comorbidities, development of a personalised plan (nutrition, physical activity, pharmacotherapy if needed), and ongoing progress monitoring.
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.

ALKA-SELTZER 2.1 g EFFERVESCENT TABLETS

Roman Raevskii

Dmytro Horobets

Roman Raevskii

Dmytro Horobets