Bisphosphonate Pregnancy: Alendronate should not be used during pregnancy (no or limited human data; reproductive toxicity in animal studies) and should not be used during breast-feeding (unknown whether excreted in human milk; risk to the infant cannot be excluded).

Alendronic Acid (Alendronate)

Brand names: Fosamax, Binosto (effervescent)

Used in: Osteoporosis Falls & Frailty

Alendronic acid is an oral bisphosphonate used to treat and prevent osteoporosis and reduce fracture risk.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: One 70 mg tablet per week

Route: Oral — must be taken on an empty stomach immediately on rising in the morning, swallowed whole with a whole glass of plain water (not less than 200 mL / 7 fl.oz), at least 30 minutes before the first food, drink or other medication of the day. Do not chew, suck or allow the tablet to dissolve in the mouth (risk of oropharyngeal ulceration). Do not lie down for at least 30 minutes and until after the first meal of the day; do not take at bedtime or before arising for the day.

Frequency: Once weekly

If a weekly tablet is forgotten, take it the following morning after realising it has been missed; do not take two tablets on the same day — continue with one tablet a week on the originally scheduled day. The optimal duration of bisphosphonate treatment for osteoporosis has not been established; re-evaluate the need for continued treatment periodically on an individual basis, particularly after 5 or more years of use. Give a calcium and vitamin D supplement if the diet is inadequate. Elderly: no dose adjustment necessary. Hepatic impairment: no dose adjustment necessary. Paediatric: not recommended under 18 years due to insufficient safety and efficacy data. Alendronic acid has not been investigated in the treatment of glucocorticoid-induced osteoporosis. Source product: Alendronic Acid 70 mg Film-coated Tablets (weekly preparation) — other strengths/regimens (e.g. daily) are not covered by this SPC.

Dose adjustments

Renal

No dose adjustment is necessary in patients with a creatinine clearance greater than 35 mL/min. Not recommended if creatinine clearance is less than 35 mL/min, as there is no experience of this.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Hypersensitivity to the active substance or to any of the excipients
Oesophageal abnormalities and other factors that delay oesophageal emptying, such as stricture or achalasia
Inability to stand or sit upright for at least 30 minutes
Hypocalcaemia

Side effects

Abdominal pain, dyspepsia, acid regurgitation, abdominal distension, constipation, diarrhoea, flatulence (common)
Oesophageal ulcers and dysphagia (common); oesophagitis and oesophageal erosions (uncommon); oesophageal stricture and oropharyngeal ulceration (rare)
Musculoskeletal pain — bone, muscle or joints (common)
Headache, dizziness, vertigo (common)
Alopecia and pruritus (common); hypersensitivity reactions including urticaria and angioedema, and symptomatic hypocalcaemia (rare). Osteonecrosis of the jaw has been reported in osteoporosis patients receiving oral bisphosphonates (§4.4)

Interactions

Section 4.5 was not captured in the fetched eMC bundle. Section 4.2 states: other drinks (including mineral water), food and some medicines are likely to reduce the absorption of alendronate — take on an empty stomach with plain water only, at least 30 minutes before any food, drink or other medication. Clinician to confirm against the full UK SPC §4.5.

Clinical monograph

How it works

It binds to bone and inhibits osteoclast-mediated bone resorption, increasing bone mineral density.

Prescribing in practice

Strict administration is essential — take on waking with a full glass of plain water, then stay upright and fasting for at least 30 minutes, to aid absorption and avoid oesophageal injury.
Avoid in oesophageal abnormalities or where the patient cannot sit or stand upright, and ensure adequate calcium and vitamin D.
Rare osteonecrosis of the jaw and atypical femoral fractures occur with long-term use; consider a dental check before starting and review the duration of therapy.

Monitoring

Review fracture risk and the need to continue (drug-holiday consideration), calcium/vitamin D status and dental health.

Counselling the patient

Take it exactly as instructed: empty stomach, plenty of water, stay upright, and wait before food or other tablets.
Report new thigh or groin pain, or dental problems.

Evidence & guidelines

First-line for osteoporotic fracture prevention (NICE TA464 / NOGG), with calcium and vitamin D repletion.

Reference: NICE CG146 (Osteoporosis); NICE TA160; FRAX tool; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

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