Drug reference

Alendronate

Bisphosphonate · Anti-osteoporotic

Also known as Alendronic acid, Alendronate sodium

BisphosphonateAnti-osteoporotic

CDSCO approved

EXCRETION

—

not curated

INTERACTIONS

—

none in our sources

PREGNANCY

Avoid.

FDA category + note

Mechanism

Alendronate, an aminobisphosphonate, primarily functions by directly inhibiting osteoclast-mediated bone resorption. It binds to hydroxyapatite in bone and is internalized by osteoclasts, leading to the suppression of their activity. This action reduces bone turnover, increases bone mineral density, and consequently lowers the risk of osteoporotic fractures.

Indications

Treatment of postmenopausal osteoporosisTreatment of osteoporosis in menPrevention and treatment of corticosteroid-induced osteoporosis in postmenopausal women not receiving hormone replacement therapyPaget diseasetreatment and prevention of osteoporosisglucocorticoid-associated osteoporosisPrevention of osteoporosis (women and men)Treatment of osteoporosis (women and men)Paget’s disease

Dosing

Adult: For postmenopausal osteoporosis: 10 mg daily by mouth, or 70 mg once weekly by mouth. For osteoporosis in men: 10 mg daily by mouth. For prevention and treatment of corticosteroid-induced osteoporosis in postmenopausal women not receiving hormone replacement therapy: 10 mg daily by mouth.
Renal adjustment: Avoid if eGFR less than 35 mL/minute/1.73 m2.
Geriatric: Potentially inappropriate (STOPP criteria) in patients with a current or recent history of upper gastrointestinal disease or bleeding (risk of relapse/exacerbation of oesophagitis, oesophageal ulcer, or oesophageal stricture).

Pharmacokinetics

Half-life

10.5 years (terminal elimination t½ in bone)

Bioavailability

<1%

Protein binding

78%

Excretion

44.9 ± 9.3%

Contraindications

Abnormalities of oesophagus
Hypocalcaemia
Other factors which delay oesophageal emptying (e.g., stricture or achalasia)
abnormalities that delay esophageal emptying
Gastroesophageal reflux
Peptic ulcer
Renal impairment

Side effects

Common

AlopeciaAnaemiaArthralgiaAstheniaConstipationDiarrhoeaDizzinessDysphagiaElectrolyte imbalanceEye inflammationFeverGastritisGastrointestinal discomfortGastrointestinal disordersHeadacheInfluenza-like illnessJoint swellingMalaiseMyalgiaNauseaOesophageal ulcerOesophagitisPainPeripheral oedemaRenal impairmentSkin reactionsTaste alteredVertigoVomitingheartburnesophageal irritationesophagitisabdominal paindiarrheaGastric irritationGastric erosionRetrosternal painFlatulenceBodyacheInitial fall in serum Ca2+ level

Serious

Anaphylactic reaction
Angioedema
Atypical femur fracture
Bronchospasm
Femoral stress fracture
Haemorrhage
Oesophageal stenosis
Osteonecrosis
Oropharyngeal ulceration
Photosensitivity reaction
Severe cutaneous adverse reactions (SCARs)
Severe oesophageal reactions (oesophagitis, oesophageal ulcers, oesophageal stricture, oesophageal erosions)
Stevens-Johnson syndrome
osteonecrosis of the jaw
fractures of the femoral shaft (most commonly associated)
esophageal ulcers
esophageal erosions

Pregnancy & lactation

Pregnancy

Avoid.

Lactation

Manufacturer advises avoid; no information available.

Drug interactions

Aceclofenac + Paracetamol

Moderate

Textbook

NSAIDs accentuate gastric irritation caused by alendronate.

Not explicitly stated, but implies caution or avoidance of co-administration if gastric irritation is a concern.

Source: KDT 7e · p345

Aceclofenac

Moderate

Textbook

NSAIDs accentuate gastric irritation caused by alendronate.

Not explicitly stated, but implies caution or avoidance of co-administration if gastric irritation is a concern.

Source: KDT 7e · p345

Antacids

Moderate

Textbook

Decreased absorption and efficacy of the bisphosphonate.

Oral bisphosphonates should be administered with a full glass of water following an overnight fast and at least 30 min before breakfast to avoid interaction with divalent cations.

Source: G&G 14e · p1060

Aspirin

Moderate

Textbook

NSAIDs accentuate gastric irritation caused by alendronate.

Not explicitly stated, but implies caution or avoidance of co-administration if gastric irritation is a concern.

Source: KDT 7e · p345

Bromfenac

Moderate

Textbook

NSAIDs accentuate gastric irritation caused by alendronate.

Not explicitly stated, but implies caution or avoidance of co-administration if gastric irritation is a concern.

Source: KDT 7e · p345

Capsaicin

Moderate

Textbook

NSAIDs accentuate gastric irritation caused by alendronate.

Not explicitly stated, but implies caution or avoidance of co-administration if gastric irritation is a concern.

Source: KDT 7e · p345

Choline Salicylate

Moderate

Textbook

NSAIDs accentuate gastric irritation caused by alendronate.

Not explicitly stated, but implies caution or avoidance of co-administration if gastric irritation is a concern.

Source: KDT 7e · p345

Coffee

Moderate

Textbook

Reduced alendronate absorption, potentially leading to reduced efficacy.

Alendronate must be taken on an empty stomach in the morning with a full glass of plain water, and the patient instructed not to lie down or take food for at least 30 min.

Source: KDT 7e · p345

Diclofenac

Moderate

Textbook

NSAIDs accentuate gastric irritation caused by alendronate.

Not explicitly stated, but implies caution or avoidance of co-administration if gastric irritation is a concern.

Source: KDT 7e · p345

Diclofenac + Paracetamol

Moderate

Textbook

NSAIDs accentuate gastric irritation caused by alendronate.

Not explicitly stated, but implies caution or avoidance of co-administration if gastric irritation is a concern.