Alendronate sodium 70 mg is a once-weekly tablet taken first thing in the morning on an empty stomach, swallowed with a full glass of plain water, followed by at least 30 minutes of staying upright before eating or drinking anything else. Getting these steps right matters more than with most medications, because improper dosing can irritate your esophagus and reduce how well the drug works.
Step-by-Step Dosing Instructions
Take your alendronate immediately after getting out of bed, before eating, drinking, or taking any other medications. This includes coffee, juice, vitamins, and even calcium supplements. Swallow the tablet with a full glass of plain water (6 to 8 ounces). Do not use mineral water, sparkling water, or any other beverage, as minerals can bind to the medication and prevent your body from absorbing it.
Do not chew, crush, or suck on the tablet. Swallow it whole. If you take the liquid formulation instead of tablets, follow it with at least 2 ounces (about a quarter cup) of plain water.
After swallowing the tablet, wait at least 30 minutes before eating your first food, drinking anything other than plain water, or taking any other pills. This 30-minute window lets the drug reach your stomach and get absorbed properly. Many people find it easiest to take their dose the moment they wake up, then go about their morning routine (showering, getting dressed) before sitting down to breakfast.
Why You Need to Stay Upright
After taking alendronate, remain sitting upright or standing for at least 30 minutes, and until after you’ve eaten your first meal. Do not lie back down in bed. This isn’t optional. The medication can cause serious irritation or ulceration of the esophagus (the tube connecting your throat to your stomach), and staying upright helps gravity move the tablet down quickly. If you can’t reliably sit or stand for 30 minutes after taking it, this medication may not be appropriate for you.
What to Do If You Miss a Dose
Since alendronate 70 mg is a once-weekly medication, pick one day of the week and take it on that same day every week. If you forget your dose, take it the next morning you remember, then return to your regular schedule on your usual day. Don’t double up by taking two tablets in the same day or on consecutive days.
Timing With Other Medications and Supplements
Calcium supplements, antacids, iron, and even multivitamins can all interfere with alendronate absorption. The key rule: nothing but plain water for at least 30 minutes after your dose. In practice, spacing calcium and other supplements to later in the day (lunchtime or evening) is the simplest approach. This separation ensures the alendronate has time to be absorbed without competing minerals blocking it.
Common Side Effects
Most side effects are digestive. In clinical trials of the 70 mg weekly dose, the most frequently reported problems were abdominal pain (3.7% of patients), indigestion (2.7%), acid reflux (1.9%), and nausea (1.9%). Bone, muscle, or joint pain affected about 2.9% of patients. Constipation, bloating, and gas occurred at lower rates. These side effects are generally mild, and following the dosing instructions carefully, especially the water and upright positioning, reduces the chance of esophageal and stomach irritation significantly.
Rare but Serious Complications
Two rare complications get the most attention. Osteonecrosis of the jaw is a condition where bone tissue in the jaw breaks down, typically after a tooth extraction or dental infection. It has been reported rarely in people taking alendronate. If you have upcoming dental surgery, let your dentist know you’re on this medication.
Atypical femur fractures, unusual breaks in the thigh bone that can happen with minimal force, have also been reported. These tend to occur in people who have been on bisphosphonate therapy for many years. Thigh or groin pain that develops while you’re on long-term treatment is worth mentioning to your doctor, as it can be an early warning sign.
How Long You’ll Take It
Alendronate isn’t typically a lifelong medication. The FDA suggests reassessing whether you still need it after 3 to 5 years. Because the drug accumulates in bone and continues to provide some protection even after you stop, many patients take what’s called a “drug holiday,” a planned break from the medication.
How long you stay on treatment depends on your fracture risk. For people at mild risk, 3 to 5 years of treatment followed by a break is often sufficient. For those at moderate risk, 5 to 10 years of treatment may be recommended, followed by a holiday of 3 to 5 years. People at high risk for fractures may benefit from continuing treatment for up to 10 years. Your doctor will typically monitor your bone density over time to decide when a break makes sense and when to restart if needed.
What Alendronate Does in Your Body
Alendronate belongs to a class of drugs called bisphosphonates. Your bones are constantly being broken down and rebuilt. In osteoporosis, the breakdown outpaces the rebuilding. Alendronate works by slowing down the cells responsible for breaking bone down, which shifts the balance back toward bone preservation and gradual strengthening. Over a course of treatment, bone mineral density at the spine and hip typically increases, with studies showing gains of several percent over the first few years.