Fosamax (Alendronate) Dosages: Your GoodRx Guide
Key takeaways:
Fosamax (alendronate) is a bisphosphonate medication. It treats osteoporosis and other bone-related conditions. It comes in multiple oral forms, including tablets and an oral solution.
The best Fosamax dosage for you depends on the condition you’re treating and your personal preferences. For osteoporosis prevention and treatment, you can take Fosamax once a week or once a day. Taking weekly Fosamax doses is considered as safe and effective as taking daily doses.
Knowing how to take Fosamax is important for getting the most out of your medication. This includes taking Fosamax 30 minutes before you eat or drink anything (or take other medications) in the morning. You should also take it with water, and remain upright for at least 30 minutes after a dose and until you eat.
Fosamax is available as both a brand-name medication and lower-cost generic. You may be able to find generic Fosamax for as low as $13.77 at certain pharmacies with a free GoodRx coupon.
Table of contents
Fosamax (alendronate) is a medication that’s prescribed to prevent and treat osteoporosis, along with other bone-related health conditions. Fosamax is classified as a bisphosphonate medication. Bisphosphate medications work by limiting the breakdown of bones.
Fosamax comes as tablets with vitamin D (Fosamax Plus D) and without, and as an oral solution. The oral solution comes in single-use bottles that contain 1 dose. Alendronate also comes as effervescent tablets (Binosto), which are dissolvable tablets that you mix with water.
Fosamax tablets without vitamin D and the oral solution are available as generic medications. The other forms are only available as brand-name medications.
Taking Fosamax correctly is key to getting the most out of the medication. This means taking it at the right time and at the right dose.
What’s the typical Fosamax (alendronate) dosage for adults?
How often you’ll take Fosamax largely depends on what condition you’re treating. Below, we’ll cover typical dosages for each of Fosamax’s FDA-approved uses, which include:
Osteoporosis treatment in men and postmenopausal women
Osteoporosis prevention in postmenopausal women
Treatment of osteoporosis caused by steroid use
Treatment of Paget’s disease (a disease of abnormal bone growth)
Osteoporosis treatment in men and postmenopausal women
Fosamax is most commonly used for treating osteoporosis in men and postmenopausal women. Typically, Fosamax is taken as a once-weekly dose of 70 mg. This is true for the tablets with vitamin D and without, the effervescent tablets, and the oral solution. Additionally, the tablets without vitamin D can be taken once daily. The recommended daily dose is 10 mg.
Fosamax tablets with vitamin D contain either 2,800 international units (IU) or 5,600 IU of vitamin D3 (cholecalciferol). Your prescriber can determine which of these options is best for you based on how much vitamin D you need weekly.
Good to know: Studies show that once-weekly alendronate doses are just as effective, and as well tolerated, as daily doses. This means that the number of people who experience fractures after alendronate treatment, and the number of people who experience side effects, are similar whether the medication is taken daily or weekly.
Osteoporosis prevention in postmenopausal women
For osteoporosis prevention in postmenopausal women, the typical Fosamax dosage is 35 mg once weekly or 5 mg once daily. Only Fosamax tablets without vitamin D are FDA approved for this use. But other alendronate-containing products may be used off-label for osteoporosis prevention, too.
Treatment of steroid-induced osteoporosis
The typical Fosamax dosage for steroid-induced osteoporosis is 5 mg once daily. However, if you’re postmenopause and you’re not receiving estrogen, the dosage is typically 10 mg daily. Only Fosamax tablets without vitamin D are FDA approved for this use. But other alendronate-containing products may be used off-label for this purpose.
Fosamax side effects: Like all medications, Fosamax can cause side effects. The most common ones are nausea and heartburn.
Comparing osteoporosis treatments: There are many osteoporosis medications available, but one may be a better option for you than the others.
Tips for increasing bone strength: You can do several things, such as strength training and eating foods high in calcium and vitamin D, to improve your bone strength as you age.
Although steroids are known to weaken bones, taking steroids doesn’t always lead to osteoporosis, especially if you use them for a short amount of time. Steroid-induced osteoporosis is more likely in older adults who take steroids for a long time. Taking high steroid doses also increases your risk.
Treatment of Paget's disease
The typical Fosamax dosage for Paget’s disease is 40 mg once daily for at least 6 months. A second treatment period with Fosamax may be considered after 6 months of not taking the medication if necessary.
What’s the typical Fosamax (alendronate) dosage for children?
Fosamax is not FDA approved for use in children. So there are no universally accepted dosage recommendations for them.
Some studies have looked at whether the medication can be used off-label to help treat pediatric osteogenesis imperfecta. This is a genetic disorder of abnormal bone formation, including weaker bones that may fracture more easily. Studies have also looked at whether Fosamax can be used to prevent steroid-induced osteoporosis in children or reduce bone pain related to some childhood cancers. But these studies have involved various dosages, so one specific dosage can’t be recommended.
How to take Fosamax (alendronate)
If you’ve been prescribed Fosamax, knowing how to take it is important. Whether you take Fosamax weekly or daily, taking it correctly will help it be as effective as possible and help you avoid side effects.
Below, we’ll cover a few instructions for how to take Fosamax:
Know when to take your alendronate medication. Take your alendronate medication 30 minutes before your first piece of food or beverage of the day. If you eat or drink anything sooner than this, your body won’t absorb the medication as well. It should also be taken 30 minutes before any other medications for the same reason.
Take it with water. All alendronate products should be swallowed with plain water (not mineral or flavored). The exact amount of water that’s recommended varies by product. For example, swallowing Fosamax tablets with at least 6-8 oz of plain water is recommended. But it’s recommended to take the effervescent tablets with at least 4 oz of plain, room temperature water. With Binosto, wait 5 minutes after the solution stops fizzing and mix it for 10 seconds, then drink it immediately. You can find more information in the Fosamax package insert for your specific product.
Stay upright. Don’t lie down or recline for at least 30 minutes after taking Fosamax, and until after you’ve eaten something. This will help Fosamax make its way to your stomach and not get stuck in your esophagus, where it can be irritating. This can help avoid serious Fosamax side effects like stomach and esophageal ulcers.
Consider taking calcium and vitamin D supplements. Fosamax can lower levels of calcium, which is important for bone health. If you don’t get enough calcium from your diet, you may need a supplement to compensate for this. People at risk of low levels of vitamin D, which includes people who are over 70 years old or who are in a nursing home, may need vitamin D supplements, too. But remember, Fosamax should be taken 30 minutes before any supplements or other medications, including calcium and vitamin D supplements.
Are there any dosage adjustments for medical conditions?
If you have kidney problems or you’re someone who needs to limit your sodium (salt) intake, there are a few things to consider if you’re prescribed Fosamax.
People with kidney problems
When you take Fosamax, it enters your bloodstream and is quickly absorbed by the bones. Any medication that doesn’t enter the bones leaves your body through the kidneys. Because your kidneys are needed to help get rid of Fosamax, it’s not recommended if you have moderate-to-severe kidney problems. This is because you may have a harder time getting rid of the medication, which can lead to increased side effects, like nausea, heartburn, and constipation.
Fosamax hasn’t been well studied in people receiving dialysis, so it’s not universally recommended in this situation. Before starting Fosamax treatment, discuss your medical history, including any past kidney problems, with your prescriber. They can help you decide if Fosamax is a safe treatment option for you.
People who need to limit sodium intake
The effervescent tablets contain a significantly larger amount of sodium than other forms of alendronate. So if you’ve been instructed by a healthcare professional to limit your sodium intake, Binosto may not be the best option for you. Your prescriber might decide that another form of alendronate is a better option in this case. People that may need to limit their sodium intake include those with heart failure or high blood pressure.
How long should you take Fosamax (alendronate)?
If you’re prescribed Fosamax for osteoporosis, treatment typically lasts between 3 to 5 years. Taking Fosamax for longer than this may increase the risk of certain negative outcomes, such as osteonecrosis of the jaw and certain types of fractures.
Taking a break from alendronate after 3 to 5 years of treatment (known as a “drug holiday”) is generally supported by experts. However, some people may benefit from returning to alendronate treatment after this break. For example, if you have a very high risk of fractures, the benefits of resuming alendronate treatment may outweigh the risks.
What happens if you miss a week of Fosamax treatment?
If you forget to take your weekly (or daily) dose of Fosamax, take a dose the morning after you remember. You should wait until the following morning because Fosamax shouldn’t be taken after you’ve already eaten or taken other medications. This means the only time you should take Fosamax is first thing in the morning.
If you take a once-weekly dose of Fosamax, this may mean that you take two doses that are less than 1 week apart. If you take the medication once daily, you will end up skipping a dose entirely, since you have to wait until the morning.
Never double up on doses to make up for a missed dose. This means you shouldn’t take more than 1 dose of Fosamax at a time, no matter what.
What should you do if you take too much Fosamax?
Taking too much Fosamax can lead to serious problems. High doses of Fosamax can cause hypocalcemia (low calcium levels), hypophosphatemia (low phosphate levels), and stomach or esophageal ulcers.
In the case of a Fosamax overdose, call 911 or go to the nearest emergency room. Your healthcare team may recommend milk or antacids to help bind alendronate.
How to save on Fosamax
Alendronate medications are available in both brand-name and lower-cost generic versions. Whichever version you choose, GoodRx may be able to help you save on your prescription.
For example, the price for a 3-month supply of once-weekly generic Fosamax 70 mg tablets may be as low as $13.77 with a GoodRx coupon at some pharmacies.
The bottom line
Fosamax (alendronate) is a medication that can help treat and prevent osteoporosis. It’s also used to treat other bone-related conditions. The best Fosamax dosage for you depends on what condition you're treating and whether you prefer a weekly or daily medication regimen. For example, if you’re treating osteoporosis, you may have the option of taking Fosamax once daily or once weekly.
Taking a weekly dose of Fosamax has been shown to be as effective, and as safe, as taking a once-daily dose for osteoporosis treatment and prevention. But no matter which option you choose, knowing how to take Fosamax is important. This includes taking Fosamax 30 minutes before your first piece of food or drink of the day and any other medications. You should also take Fosamax with water, and remain upright for at least 30 minutes after a dose and until you eat.
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References
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The Alendronate Once-Weekly Study Group, et al. (2009). Two-year results of once-weekly administration of alendronate 70 mg for the treatment of postmenopausal osteoporosis. Journal of Bone and Mineral Research.
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