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Terms Of Use


Brand Name(s) : Fosamax
Side Effects


Alendronic acid should be used with caution in:

It should not be used in:
patients with allergies to bisphosphonates or any of the other ingredients in the medicine, those with problems or abnormalities with the oesophagus (the tube that connects your mouth with your stomach) such as narrowing or difficulty swallowing, patients who cannot stand or sit upright for at least 30 minutes, those with hypocalcaemia (low blood calcium levels), or women who are pregnant or who are breast-feeding.

Also see list of precautions and interactions.


Store below 25°C.


Alendronic acid is used to treat osteoporosis.

It is a type of drug known as a bisphosphonate.

It is used to prevent bone loss in women after they have been through the menopause, and bone loss in men and in people taking steroids.

In general this drug is used to prevent bone loss in post-menopausal women, men and steroid users. It is also used to help rebuild bone and reduce the risk of spine and hip fractures.

Benefits of being on this drug can include an increase in bone density and a decrease in likelihood of fractures.

Listed below are the typical uses of alendronic acid.

  • Treatment of osteoporosis in post-menopausal women to prevent fractures
  • Treatment of osteoporosis in men to prevent fractures
  • Prevention and treatment of corticosteroid-induced osteoporosis and prevention of bone loss in post-menopausal women considered at risk of developing osteoporosis.


How often do I take it?

  • Alendronic acid can be taken once a day or once a week, depending on the dose required.
  • To help the tablet reach your stomach quickly and reduce any possible irritation you should:- take your medication first thing in the morning, before any other food or drink with a full glass of plain water only (not less than 200ml or 7 fl. oz). You should not take your tablet with mineral water, coffee, tea, fruit juice, or milk. Do not chew the tablet, or allow it to dissolve in your mouth.Stay fully upright after taking alendronic acid (sit, stand or walk) for at least 30 minutes. Do not lie down until after you have eaten your first food of the day.
  • Alendronic acid is only effective if it is taken when your stomach is empty, so do not have any food, drink, or any other medicines, including antacids, calciumsupplements and vitamins until at least 30 minutes after taking alendronic acid.
  • Do not take alendronic acid at bedtime or before getting up for the day.
  • Use this medication regularly or for duration of prescription in order to get the most benefit from it.
  • Remember to use it at the same time each day/week - unless specifically told otherwise by your doctor.
  • Certain medical conditions may require different dosage instructions as directed by your doctor.

What dose?

  • Dosage is based on your age, gender, medical condition, response to therapy, and use of certain interacting medicines.

Do I need to avoid anything?

  • There have been side effects reported with alendronic acid that may affect the ability to drive or operate machinery (e.g. blurred vision, dizziness, severe muscle, joint or bone pain). If affected do not drive or operate machinery. You should avoid eating or drinking at the same time as taking your medicine. Consult your doctor or pharmacist for more details.

When can I stop?

  • It is important to continue taking this medication even if you feel well, unless your doctor tells you to stop.


  • Heartburn (a burning feeling in the chest, behind the breastbone or gullet)
  • Difficulty swallowing
  • Pain upon swallowing
  • Ulceration of the oesophagus (the tube that connects your mouth with your stomach)
  • Chest pain
  • Muscle, joint and back pain
  • Bone, muscle and/or joint pain
  • Stomach pain
  • Uncomfortable feeling in the stomach or belching after eating
  • Constipation
  • Full or bloated feeling in the stomach
  • Diarrhoea
  • Flatulence
  • Headache
  • Feeling sick (nausea)
  • Vomiting
  • Irritation or inflammation of the oesophagus or stomach
  • Black or tar-like stools
  • Rash
  • Itching
  • Redness of the skin.

If any of these persist or you consider them severe then contact doctor or pharmacist.

Tell your doctor immediately if you develop any of the following symptoms: difficulty and/or pain when swallowing, pain behind the breastbone or new or worsened heartburn .

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

A serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching/swelling (especially of the face/tongue/throat), dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

The Yellow Card Scheme allows you to report suspected side effects from any type of medicine (which includes vaccines, herbals and over the counter medicines) that you are taking. It is run by the medicines safety watchdog called the Medicines and Healthcare products Regulatory agency (MHRA). Please report any suspected side effect on the Yellow Card Scheme website.


Before taking alendronic acid, tell your doctor or pharmacist if you are allergic to it; or to other bisphosphonates; or if you have any other allergies.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: allergies to bisphosphonates or any of the other ingredients, problems or abnormalities with the oesophagus (the tube that connects your mouth with your stomach) such as narrowing or difficulty swallowing, if you cannot stand or sit upright for at least 30 minutes, have low blood calcium levels, or if you are pregnant or breastfeeding.

Before using this medication, tell your doctor or pharmacist your medical history, especially any of the following: any kidney problems, allergies, swallowing or digestive problems including ulcers, low blood calcium levels and/or a vitamin-D deficiency, gum disease, or if you need a tooth removed.

A dental examination should be considered before you start treatment with alendronic acid if you have cancer, are undergoing chemotherapy or radiotherapy, are taking steroids, do not receive routine dental care, or have gum disease.

Before having surgery, tell your doctor or dentist that you are taking this medication.

Alcohol intake is not known to affect alendronic acid.

The elderly: alendronic acid can be used in the elderly.

Pregnancy and breastfeeding - please ensure you read the detailed information below


Alendronic acid is intended for use in postmenopausal women. Do not take it if you are, or think you may be, pregnant.

It is sensible to limit use of medication during pregnancy whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


It is not known if alendronic acid passes into breast milk. Given that alendronic acid is intended for use in post-menopausal women, it should not be used in breastfeeding women.

It is sensible to limit use of medication during breastfeeding whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


Before using this medicine, tell your prescriber of all the medicines you are taking including prescription medicines and medicines you have bought over the counter without a prescription. Tell your prescriber if you are taking vitamins or complementary remedies such as herbal products, as these can also interact with medicines.

If you are taking more than one medicine, these may interact with each other. Your prescriber may decide to use medicines which interact with each other if the benefit outweighs the risks. In these cases, the dose of your medicines may need to be adjusted or you may be monitored more closely.

Alendronic acid can interact with food and drink (mineral water, milk, tea, coffee), calcium supplements, antacids, oral iron and some oral medicinal products; as these can interfere with its absorption.

This information does not contain all possible interactions. Therefore, tell your prescriber of all the products you are using before taking this medicine.

If you have a question or want to discuss anything about your medicine, speak to your local pharmacist.


If you take too many tablets by mistake, drink a full glass of milk and contact your doctor immediately. Do not make yourself vomit, and do not lie down.

If you think you, or someone you care for, might have accidentally taken more than the recommended dose of alendronic acid or intentional overdose is suspected, contact your local hospital, GP or if in England call 111. In Scotland call NHS 24. In Wales, call NHS Direct Wales. In the case of medical emergencies, always dial 999.


For the daily dose: If you miss a dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

For the weekly dose: If you miss a dose, just take one tablet on the morning after you remember. Do not take two tablets on the same day. Return to taking one tablet once a week, as originally scheduled on your chosen day.

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Source: Selected from data included with permission and copyrighted by Boots UK Limited. This copyrighted material is sourced from a licensed data provider and is not for distribution, except as may be authorised by the applicable terms of use.
CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgement of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse events, nor should it be construed to indicate that use of a particular medicine is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any medicine, changing any diet, or discontinuing any course of treatment.

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