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What is Alka-Seltzer original used for?
- Relieving mild to moderate pain including rheumatic and muscular pain, sprains and strains, backache, nerve pain (neuralgia), migraine, headache, toothache, sore throat, period pain.
- Lowering a high temperature (fever).
- Relieving symptoms of colds and flu.
How does Alka-Seltzer original work?
Alka-Seltzer original effervescent tablets contain three active ingredients, aspirin, sodium hydrogen carbonate and citric acid.
Aspirin belongs to a group of medicines called non-steroidal anti-inflammatory drugs (NSAIDs). It works by blocking the action of an enzyme in the body called cyclo-oxygenase (COX).
COX is involved in making substances in the body known as prostaglandins, in response to injury and in certain conditions. The prostaglandins cause pain, swelling and inflammation. Aspirin reduces inflammation and pain by reducing the production of these prostaglandins.
Aspirin brings down a fever by reducing the production of prostaglandins in the brain. Fever is associated with an increase in prostaglandins in the brain, which cause the body temperature to increase.
The sodium hydrogen carbonate and citric acid react with water to make a fizzy solution that is quickly absorbed into the bloodstream.
How do I take Alka-Seltzer original?
- Alka-Seltzer tablets should be dissolved in a glass of water before taking.
- Adults aged 16 years and over should take two tablets every four to six hours as needed. Do not take more than eight tablets in 24 hours.
- If symptoms persist despite treatment, get medical advice from your doctor or pharmacist.
- Do not use Alka-Seltzer for more than three days except on medical advice.
Who shouldn't take Alka-Seltzer original?
- Children and adolescents under 16 years of age, unless on the advice of a doctor.
- People allergic to any ingredient of the medicine (always check the packet for the inactive ingredients of the medicine if you know you have specific allergies).
- People who have ever had an allergic reaction after taking ibuprofen or other NSAIDs such as diclofenac (for example an asthma attack, itchy rash, nasal inflammation (rhinitis) or swelling of the lips, tongue and throat).
- People with an active peptic ulcer, perforation (hole) or bleeding in the gut, or a history of these problems.
- People with blood clotting disorders such as haemophilia.
- Women who are breastfeeding.
- Women in the third trimester of pregnancy.
- People taking 15mg or more of methotrexate weekly.
Who should get medical advice before taking Alka-Seltzer original?
- People who suffer from asthma.
- People with a history of disorders affecting the stomach or intestines.
- People with kidney or liver problems.
- People with heart disease or high blood pressure.
- People taking anticoagulant or 'blood thinning' medicines.
- People who are just about to have or have recently had surgery.
- People who suffer from gout.
- People on a sodium-restricted diet.
- People with an enzyme deficiency called G6PD deficiency.
Can I take Alka-Seltzer original while pregnant or breastfeeding?
- Alka-Seltzer original should not be taken by women in the third trimester of pregnancy. If aspirin is used in the third trimester it may delay labour, increase the length of labour, increase the risk of bleeding in the mother and baby and cause complications in the newborn baby. Get medical advice from your doctor before taking Alka-Seltzer during any other stage of pregnancy.
- Alka-Seltzer original should not be taken by breastfeeding mothers because aspirin passes into breast milk and may be harmful to the nursing infant. Ask your pharmacist for advice on what medicines you can take if you're breastfeeding.
What are the possible side effects of Alka-Seltzer original?
Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with Alka-Seltzer. Just because a side effect is stated here doesn't mean that all people using this medicine will experience that or any side effect.
- Disturbances of the gut such as nausea, vomiting, diarrhoea or abdominal pain. This can be helped by taking Alka-Seltzer with or after food.
- Ulceration or bleeding in the stomach or intestine. Stop taking Alka-Seltzer and consult your doctor immediately if you get any sign of bleeding from your stomach or bowels while taking it, for example vomiting blood and/or passing black/tarry/bloodstained stools.
- Changes in liver function.
- Increased time taken to stop bleeding.
- Allergic reactions such as skin rashes, swelling of the lips, tongue and throat (angioedema) or narrowing of the airways (bronchospasm). Get immediate medical advice if you think you've had an allergic reaction to Alka-Seltzer.
Read the leaflet provided with Alka-Seltzer or consult your doctor or pharmacist if you want any more information about possible side effects. If you think you have experienced a side effect, did you know you can report this using the yellow card website?
Can I take Alka-Seltzer original with other medicines?
If you're already taking any medicines it's best to check with your pharmacist before taking Alka-Seltzer as well, to make sure that the combination is safe.
Don't take Alka-Seltzer with anti-inflammatory painkillers (NSAIDs) such as ibuprofen, diclofenac or naproxen, because this increases the chance of getting side effects on the gut. People taking selective inhibitors of COX-2 such as celecoxib or etoricoxib should avoid taking Alka-Seltzer for the same reason.
It's fine to take Alka-Seltzer with paracetamol. You can also take it alongside opioid-type painkillers such as codeine, co-codamol, tramadol or morphine.
You're more at risk of ulceration or bleeding in your gut if you take Alka-Seltzer with corticosteroids such as prednisolone. There may also be an increased risk of bleeding in the gut if you take Alka-Seltzer with other medicines that can increase the risk of bleeding, such as those below. If you're taking one of these you shouldn't take Alka-Seltzer unless you've checked with your pharmacist first:
- anti-blood-clotting (anticoagulant) medicines such as warfarin, dabigatran, apixaban, edoxaban, rivaroxaban, heparin and low molecular weight heparins such as enoxaparin
- antiplatelet medicines to reduce the risk of blood clots or 'thin the blood', eg dipyridamole, clopidogrel, prasugrel, low-dose aspirin
- erlotinib
- ginko biloba (a herbal remedy)
- iloprost
- SSRI antidepressants, eg fluoxetine, paroxetine, citalopram
- venlafaxine.
Don't take Alka-Seltzer if you're taking the medicine methotrexate, because aspirin can reduce the removal of methotrexate from the body and increase its side effects. The two should not usually be used together, unless on the advice of a doctor.
There may be an increased risk of side effects if aspirin is taken with acetazolamide.
Last updated 07.12.2016