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Alendronate

Brand names: Fosamax, Binosto

Alendronate strengthens bones and lowers the risk of fractures from osteoporosis.

Brand namesFosamax, Binosto
Type of medicineBisphosphonate (bone medicine)
Prescription?Prescription
ImportantThis page is general information, not a prescription. Don't start, stop, or change a medicine without talking to your provider or pharmacist.

Overview

It's often taken once a week. It must be taken a special way so it's absorbed and doesn't irritate the throat.

What it's used for

  • Osteoporosis in women after menopause and in men
  • Bone loss from steroid medicines
  • Paget's disease of bone

How to take it

  • Take it first thing in the morning, with a full glass of plain water only, before any food, drink, or other medicine.
  • Stay upright (sitting or standing) and don't eat for at least 30 minutes after.
  • Get enough calcium and vitamin D, but take them at a different time of day.

Your dose depends on your health and other medicines. Always follow your prescription label, and ask your pharmacist if anything is unclear.

Side effects

Common side effects

  • Heartburn or stomach pain
  • Constipation or diarrhea
  • Bone, joint, or muscle pain
Call your provider todayTrouble or pain swallowing, chest pain, or new or worse heartburn
Call your provider todayNew thigh or groin pain (rare unusual thigh fracture)
Call your provider todayJaw pain, loose teeth, or a sore in the mouth that won't heal
Call your provider todaySevere bone, joint, or muscle pain

Warnings

  • Not for people who can't sit or stand upright for 30 minutes, or with some esophagus problems or low calcium.
  • Tell your dentist you take it.
  • Your provider may suggest a break after several years.

Other medicines, foods, and alcohol

  • Calcium, iron, antacids, coffee, and juice block absorption if taken too close.
  • NSAIDs may add to stomach irritation.

Tell your provider and pharmacist about every medicine, vitamin, and supplement you take.

Pregnancy and breastfeeding

Not used in pregnancy.

Missed doses, overdose, and storage

If you miss a dose

Weekly dose: take it the next morning (following the usual rules), then go back to your usual day. Don't take two on the same day.

If someone takes too much

Call Poison Control at 1-800-222-1222 or get help online at poison.org. Call 911 if the person collapses, has a seizure, has trouble breathing, or can't be woken.

Storing it

Store at room temperature, away from heat and moisture (not in the bathroom), and out of reach of children and pets.

Conditions it's used for

Sources

Last updated 2026-11-13.