Alendronic acid
Also sold as: Fosamax
Prescription neededBone health
Comes as:Tablet
Usual adult dose
Usual adult dose: 70 mg once a week (or 10 mg once a day). Take first thing in the morning on an empty stomach with a full glass of plain water, stay upright, and do not eat, drink or take other medicines for at least 30 minutes.
Your doctor may give you a different dose. Children's doses depend on weight.
Side effects
Common
- heartburn
- stomach pain
- constipation or diarrhoea
- bone or muscle pain
Serious — get help
Stop taking it and see a doctor straight away if you notice:
- pain on swallowing or chest pain (food pipe irritation)
- jaw pain or loose teeth
- new pain in the thigh or groin
Do not take it, or take care, if
- Unable to stand or sit upright for 30 minutes
- Narrowing or other problems of the food pipe
- Low calcium in the blood (correct it first)
- Serious kidney disease
- Dental surgery planned (tell your dentist)
Interactions
Medicines that can react with this one.
Moderate3 medicinesTake together only with care. Ask your doctor or pharmacist.
- Aluminium hydroxide + Magnesium hydroxide
Antacids block absorption of alendronic acid; wait at least 30 minutes after the tablet.
- Calcium carbonate
Calcium blocks absorption of alendronic acid; take alendronic acid first and wait at least 30 minutes.
- Calcium carbonate + Colecalciferol
Calcium blocks absorption of alendronic acid; take alendronic acid first and wait at least 30 minutes.