Fosamax^® (Tablets) Instructions for Use

ATC Code

M05BA04 (Alendronic acid)

Active Substance

Alendronic acid (Rec.INN registered by WHO)

Clinical-Pharmacological Group

Bone resorption inhibitor for osteoporosis

Pharmacotherapeutic Group

Bone resorption inhibitor – bisphosphonate

Pharmacological Action

Inhibitor of bone resorption. An aminobisphosphonate, it is an analog of pyrophosphate.

The mechanism of action is associated with the suppression of osteoclast activity.

It stimulates osteogenesis, restores a positive balance between bone resorption and restoration, progressively increases bone mineral density (regulates phosphorus-calcium metabolism), and promotes the formation of bone tissue with a normal histological structure.

Pharmacokinetics

Taking alendronic acid immediately before, during, or after a meal leads to a decrease in bioavailability.

When taken with coffee or orange juice, the bioavailability of sodium alendronate is reduced by approximately 60%.

After oral administration at therapeutic doses, the concentration of alendronate in blood plasma is usually below the lowest detectable concentration (less than 5 ng/ml).

It is temporarily distributed in soft tissues, then rapidly redistributes to bones or is excreted in the urine.

Plasma protein binding is approximately 78%.

It is not metabolized.

It is excreted mainly by the kidneys.

The terminal elimination half-life (T_1/2) can be more than 10 years, which is associated with the release of the active substance from the bones.

Indications

Treatment and prevention of osteoporosis in postmenopausal women. Treatment of osteoporosis in men to increase bone mass. Treatment of glucocorticoid-induced osteoporosis in men and women. Paget’s disease of bone in men and women.

ICD codes

Dosage Regimen

Take one tablet once daily or one 70 mg tablet once weekly, depending on the prescribed strength and indication.

For treatment of osteoporosis in postmenopausal women and to increase bone mass in men with osteoporosis, the dose is 10 mg once daily or 70 mg once weekly.

For prevention of osteoporosis in postmenopausal women, the dose is 5 mg once daily or 35 mg once weekly.

For treatment of glucocorticoid-induced osteoporosis in men and women, the recommended dose is 5 mg once daily. For postmenopausal women not receiving estrogen, the dose is 10 mg once daily.

For treatment of Paget’s disease of bone in men and women, the dose is 40 mg once daily for six months.

Take immediately upon rising for the day, at least 30 minutes before the first food, beverage, or other medication.

Swallow the tablet with a full glass (6-8 oz) of plain water only. Do not use mineral water, coffee, tea, or juice.

After swallowing the tablet, remain fully upright (sitting or standing). Do not lie down for at least 30 minutes and until after the first food of the day.

Do not chew or suck the tablet to avoid oropharyngeal ulceration.

Re-evaluate patients with Paget’s disease after a six-month treatment-free period; retreatment may be necessary.

Adverse Reactions

From the digestive system: pain in the epigastric region; rarely – constipation, diarrhea, flatulence, dysphagia.

From the metabolism: asymptomatic hypocalcemia.

Dermatological reactions: skin rash, erythema.

Other: headache, myalgia.

Contraindications

Esophageal stricture, achalasia, the patient’s inability to stand or sit upright for at least 30 minutes after taking the drug, hypocalcemia, hypersensitivity to alendronic acid.

Use in Pregnancy and Lactation

Adequate and strictly controlled clinical studies on the safety of alendronic acid use during pregnancy and lactation have not been conducted.

If it is necessary to use during lactation, breastfeeding should be discontinued.

In experimental studies on rats, it was shown that Alendronic acid at doses of 2 mg/kg/day and higher causes discoordination of labor due to hypocalcemia; at doses above 5 mg/kg/day, a decrease in fetal weight was noted.

Use in Renal Impairment

Use is not recommended in severe renal impairment.

Pediatric Use

Use in children is not recommended.

Special Precautions

Use is not recommended in severe renal impairment, and in children.

Use with caution in gastrointestinal diseases in the acute phase.

Before starting treatment, patients with mineral metabolism disorders should undergo their complete correction.

The interval between taking alendronic acid and other drugs should be at least 1 hour.

Drug Interactions

Concomitant oral administration with other drugs and products containing calcium impairs the absorption of alendronic acid.

In postmenopausal women receiving estrogens, no adverse effects associated with the use of alendronic acid were noted.

In clinical studies, an increase in the frequency of adverse reactions from the digestive system was observed when alendronic acid was used at a dose of more than 10 mg/day against the background of acetylsalicylic acid therapy.

Storage Conditions

Store at 15°C (59°F) to 25°C (77°F). Keep in original packaging, protected from light. Keep out of reach of children.

Dispensing Status

Rx Only

Important Safety Information

This information is for educational purposes only and does not replace professional medical advice. Always consult your doctor before use. Dosage and side effects may vary. Use only as prescribed.