Bone & metabolism
Bisphosphonates
First-line drugs to strengthen bone and reduce fracture risk in osteoporosis.
Education and reference only. This is a plain-language class overview — it deliberately contains no doses. Always check the current Summary of Product Characteristics (SmPC), the BNF and your local formulary before prescribing or administering any medicine.
What it is
Bisphosphonates are the mainstay of osteoporosis treatment, reducing the risk of fragility fractures. They are also used in some cancers affecting bone and in high blood calcium.
How it works
They bind to bone and slow the cells (osteoclasts) that break it down, tipping the balance towards stronger bone over time and lowering fracture risk.
In practice
In practice the everyday challenges with oral bisphosphonates are the strict dosing routine and adherence: they must be taken on an empty stomach with plenty of water, sitting upright, and apart from food and other tablets, to work and to avoid oesophageal irritation. Correct any vitamin D or calcium deficiency first, attend to dental health before starting because of the rare jaw risk, and review the need for continued treatment after a few years ("drug holiday").
Examples
Practical use
How to take it & use it well
- Take alendronic acid first thing in the morning on an empty stomach, with a full glass of plain water only, not other drinks.
- Stay sitting or standing upright and do not lie down for a while afterwards, to protect your gullet from irritation.
- Wait the recommended time before eating, drinking anything else or taking other medicines.
- Many people take it once a week on the same day, so pick a day that is easy to remember.
- If you forget your weekly dose, take it the next morning and then return to your usual day; do not take two doses in one day.
- Look after your teeth and tell your dentist you take it, as dental health matters with this medicine.
Common uses
- Osteoporosis (fracture prevention)
- Bone protection with long-term steroids
- Some cancers and hypercalcaemia (specialist use)
Monitoring
- Renal function and calcium/vitamin D status
- Dental health before and during treatment
- Need for continued therapy reviewed periodically
Weighing it up
Advantages & disadvantages
Advantages
- They strengthen bone and reduce the risk of fractures in osteoporosis.
- Weekly dosing means many people only take it once a week.
- They are well established and have good long-term evidence behind them.
- They are inexpensive and widely available.
- They can be combined with calcium and vitamin D advice to support bone health.
Disadvantages
- The strict morning routine of water, staying upright and waiting before food can be inconvenient.
- They can irritate the gullet, causing heartburn, swallowing problems or chest discomfort if taken incorrectly.
- There is a rare risk of jaw bone problems, especially after dental procedures, which is why dental care matters.
- They can cause flu-like aches, particularly with the first doses.
- They are not suitable for everyone, including some people with swallowing problems or reduced kidney function.
Key safety principles
What to watch for
- Oesophageal irritation with oral forms — take correctly and stop if swallowing pain develops.
- Rare but serious: osteonecrosis of the jaw and atypical femoral fractures — attend to dental health and report thigh/groin pain.
- Correct low calcium and vitamin D first; caution in significant renal impairment.
Key interactions
What to avoid or check alongside
- Calcium and iron supplements, and antacids, bind the medicine and stop it being absorbed, so they must be taken later.
- Other drinks such as coffee, juice and milk reduce absorption, which is why only plain water is used.
- Anti-inflammatory painkillers can add to the risk of stomach and gullet irritation.
- Taking it with other morning medicines reduces its absorption, so it should be taken alone first.
- Tell your dentist and doctor you take it before any dental surgery, as it affects jaw healing.
Patient & carer advice
- Follow the dosing instructions exactly — upright, empty stomach, plenty of water
- Report difficulty or pain swallowing, or new thigh/groin pain
- Keep up with dental check-ups and mention you take this medicine
Use with
Related clinical calculators
Dose and risk decisions for this class often depend on renal function, weight or bleeding/stroke risk. These tools help:
Answers
Bisphosphonates: frequently asked questions
Why do I have to stay upright after taking it?
The tablet can irritate the gullet if it lingers there. Staying upright and not lying down for the recommended time helps it pass into the stomach safely.
Why only plain water and no breakfast straight away?
Food, other drinks and supplements stop the medicine being absorbed. Taking it with plain water on an empty stomach and waiting before eating gives the best effect.
What is the jaw concern I have heard about?
Rarely, bisphosphonates are linked to a jaw bone problem, mostly after dental procedures. Good dental care and telling your dentist you take it reduce the risk.
What if I miss my weekly dose?
Take it the next morning following the usual routine, then go back to your normal chosen day. Do not take two doses on the same day.
Do I still need calcium and vitamin D?
Often yes, as adequate calcium and vitamin D support bone health and help the medicine work. Take any calcium supplement at a separate time of day.
Authoritative sources
Always verify against the source
This overview is for orientation. For doses, interactions, contra-indications and the full monograph, use:
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