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Alka-Seltzer Original

Active Ingredient:
acetylsalicylic acid
Company:  
Bayer plc See contact details
ATC code: 
N02BA01
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About Medicine
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General Sales List
Healthcare Professionals (SmPC) Patient Leaflet (PIL)
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The Patient Information Leaflet (PIL) is the leaflet included in the pack with a medicine.
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Last updated on emc: 04 Jun 2025
{pdf} View or print the patient leaflet as PDF

Below is a text only representation of the Patient Information Leaflet (ePIL).

The text only version may be available in large print, Braille or audio CD. For further information call emc accessibility on {phone} 0800 198 5000. The product code(s) for this leaflet is: PL 00010/0511.

{printer} Print patient leaflet as text only

Alka-Seltzer Original

PATIENT INFORMATION LEAFLET

Alka-Seltzer®

ORIGINAL

Aspirin

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

Always take this medicine exactly as described in this leaflet or as your doctor or pharmacist has told you.

  • Keep this leaflet. You may need to read it again.
  • Ask your pharmacist if you need more information or advice.
  • 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.
  • You must contact a doctor if you do not feel better or if you feel worse after 3 days.

WHAT IS IN THIS LEAFLET:

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

1. WHAT ALKA-SELTZER® ORIGINAL IS AND WHAT IT IS USED FOR

Alka-Seltzer Original are effervescent tablets which dissolve in water to give a sparkling solution.

The active substance is aspirin (acetylsalicylic acid).

Aspirin belongs to a group of medicines known as non-steroidal anti-inflammatory drugs (NSAIDS). It is used for the treatment of pain and reduction of fever and also has anti-inflammatory properties.

Alka-Seltzer Original can be used for the:

  • Treatment of mild to moderate pain including headache, migraine, backache (including lumbago), nerve pain (neuralgia and sciatica), period pain, toothache and sore throat.
  • Symptomatic relief of colds and influenza.
  • Relief of rheumatic pain (arthritis), muscle tenderness and stiffness (including fibrositis), muscular aches and pains, the pain of joint swelling and stiffness, strains and sprains.
  • Effective reduction of high temperature.

2. WHAT YOU NEED TO KNOW BEFORE YOU TAKE ALKA-SELTZER® ORIGINAL
DO NOT take Alka-Seltzer Original if you:
  • Are allergic (hypersensitive) to aspirin, any other salicylates (eg aloxiprin) or any of the other ingredients of Alka-Seltzer Original (see Section 6).
  • Have history of hypersensitivity reactions (eg asthma, rhinitis, urticaria) induced by pain relieving or anti-inflammatory medicines (eg NSAIDS or salicylates).
  • Have severe kidney or liver problems.
  • Have severe heart problems.
  • Have a disorder which causes excessive bleeding such as haemophilia.
  • Have, or have had, a stomach or duodenal ulcer.
  • Are on a high dose of methotrexate (15mg per week or more). If you are not sure, check with your doctor. Also see ‘Other medicines and Alka-Seltzer Original’.
  • Are in the last 3 months of your pregnancy.
  • Are breastfeeding.

Warnings and precautions

Talk to your doctor before taking Alka-Seltzer Original if you:

  • Are allergic (hypersensitive) to any other pain relieving, anti-rheumatic or anti-inflammatory medicines (eg NSAIDS). For more information see section 4 ‘Possible Side Effects’.
  • Suffer from tightness in the chest or asthma.
  • Have low uric acid excretion, which is commonly associated with gout.
  • Have a history of gastrointestinal disorders (regular stomach upsets).
  • Have a deficiency in glucose-6-phosphate dehydrogenase (G6PD), since you may experience anaemia.
  • Have kidney, liver, heart or blood circulation problems.
  • Are about to have surgery. Before the operation tell the doctor or surgeon that you are taking aspirin.
  • Are in the first 6 months of pregnancy. If you are not sure whether any of the above apply to you, speak to a doctor or pharmacist before taking Alka-Seltzer Original.

Children:

Aspirin can cause Reye's syndrome when it is given to children. Reye's syndrome is a very rare disease, which can be fatal. For this reason aspirin should not be given to children under 16 years, unless your doctor tells you to.

Other medicines and Alka-Seltzer Original:

Please tell your doctor or pharmacist if you are taking or have recently taken any other medicines, including medicines obtained without a prescription.

Aspirin can affect the way in which some medicines work. These medicines include:

  • Medication to prevent blood clotting (eg warfarin, heparin, ticlopidine).
  • Medication to treat heart problems or to lower blood pressure (eg ACE inhibitors or digoxin).
  • Medication to treat gout.
  • Diuretics (to treat water retention).
  • Medication to treat epilepsy (eg sodium valproate, phenytoin).
  • Medication to lower blood sugar if you are diabetic.
  • Methotrexate (to treat psoriasis, rheumatoid arthritis, Crohn’s disease and some types of cancer).
  • Any pain-relieving or anti-inflammatory medicines.
  • Some antidepressants known as SSRIs (eg fluoxetine, paroxetine).
  • Medication to treat Addison’s disease (eg corticosteroids except hydrocortisone).
  • Corticosteroids

Alka-Seltzer Original with alcohol:

Avoid taking alcohol while taking Alka-Seltzer Original.

Pregnancy, breastfeeding and fertility:

Do not take Alka-Seltzer Original if you are in the last 3 months of pregnancy as it could harm your unborn child or cause problems at delivery. Aspirin can cause kidney and heart problems in your unborn baby. It may affect your and your baby’s tendency to bleed and cause labour to be later or longer than expected.

You should not take this product during the first 6 months of pregnancy unless absolutely necessary and advised by your doctor.

Do not take Alka-Seltzer Original if you are breastfeeding. The product belongs to a group of medicines which may impair the fertility in women. This effect is reversible on stopping the medicine. Speak to your doctor before taking this medicine if you are trying for a baby.

Always ask your doctor or pharmacist for advice before taking any medicine.

Alka-Seltzer Original contains sodium:

This medicine contains 477 mg sodium (main component of cooking/table salt) in each tablet. This is equivalent to 23.85% of the recommended maximum daily dietary intake of sodium for an adult.

3. HOW TO TAKE ALKA-SELTZER® ORIGINAL

Follow the directions below closely. You should ask your doctor or pharmacist if you are unsure how to use this medicine.

Alka-Seltzer Original tablets must always be dissolved in water before use.

Adults and children over 16:

Two tablets dissolved in half a glass (100ml) of water may be taken every 4 hours as required. You should not take more than 8 tablets in 24 hours.

Not recommended in children under 16.

Make sure you follow the dosage instructions and do not take more than the stated dose.

Do not take Alka-Seltzer Original for more than 3 days in a row. If you do not get better, talk to your doctor.

If you take more Alka-Seltzer Original than you should:

If you think you have taken too many tablets you should go to your nearest Accident and Emergency Department or contact your doctor immediately. Take this leaflet with you and any packaging to show what you have taken.

4. POSSIBLE SIDE EFFECTS

Like all medicines Alka-Seltzer Original can cause side effects although not everybody gets them.

If you experience any of the following side effects, stop taking Alka-Seltzer Original and go to your nearest Accident and Emergency Department or doctor immediately:

  • An allergic reaction. Signs of allergic reaction may include: difficulty in breathing or swallowing, swelling of the face, lips, throat or tongue, skin rashes or itching, large or itchy wheals on the skin, attacks of sneezing, runny nose and itching eyes or water retention, heart racing.
  • Skin reddening, blistering of lips, eyes or mouth, skin peeling.
  • Mild stomach pain and heartburn. These are the most common side effects but can usually be avoided if aspirin is taken with food.
  • Stomach ulcer or perforation, stomach bleeding, which may result in black or tarry stools, nausea, diarrhoea, vomiting.
  • Dizziness or ringing in the ears.
  • Increased bleeding/blood thinning (if you cut or injure yourself), including bruises, nose bleeds, bleeding gums.
  • Internal bleeding which may result in anaemia causing weakness, increased tiredness and pale skin.
  • An asthma attack if you are asthmatic and sensitive to aspirin, breathing difficulties (bronchospasm).
  • Changes in normal liver activity in blood tests (very rare).
  • Runny nose, blocked nose.
  • Kidney problems.

Reporting of side effects:

If you get any side effects, talk to your doctor, pharmacist or nurse. This includes any possible side effects not listed in this leaflet. You can also report side effects directly via the Yellow Card Scheme at: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store. By reporting side effects you can help provide more information on the safety of this medicine.

5. HOW TO STORE ALKA-SELTZER® ORIGINAL

Keep out of the sight and reach of children.

Do not store above 25°C. Store in a dry place. This product should be stored in its original carton.

This product is packaged in pouches containing 1 or 2 tablets. If the pouch is damaged or if a tablet is powdery or discoloured, do not use the tablet.

Do not use Alka-Seltzer Original after the expiry date which is stated on the carton and on the foil pouch. The expiry date refers to the last day of that month.

Do not throw away any medicines via wastewater or household waste. Ask your pharmacist how to throw away medicines you no longer use. These measures will help protect the environment.

6. CONTENTS OF THE PACK AND OTHER INFORMATION
What Alka-Seltzer Original contains:

The active substance is aspirin (acetylsalicylic acid) (324mg per tablet).

The other ingredients are sodium hydrogen carbonate and citric acid.

See Section 2 for sodium advice.

What Alka-Seltzer Original looks like and contents of the pack:

Alka-Seltzer Original comes in cartons containing 2, 8, 10, 12, 20 or 30 white effervescent tablets packaged in foil pouches. Not all pack sizes may be marketed.

Marketing Authorisation Holder:
Bayer plc
400 South Oak Way
Reading
RG2 6AD
UK

Manufacturer:
Bayer Bitterfeld GmbH
OT Greppin
Salegaster Chaussee 1
06803 Bitterfeld-Wolfen
Germany

This leaflet was last revised in April 2025.

Alka-Seltzer® is a registered trademark.

Bayer

91527612

Bayer plc
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Address
400 South Oak Way, Reading, Berkshire, RG2 6AD
Medical Information e-mail
[email protected]
WWW
http://www.bayer.co.uk
Telephone
+44 (0)118 206 3000