Could I be taking any medications that affect bone health?
There are several types of medications that can put you at greater risk for developing osteopenia and osteoporosis. These types of medications are believed to decrease bone mass either by accelerating bone breakdown or by interfering with new bone formation. Some drugs may also interfere with the body's use of vitamin D and parathyroid hormone. However, certain medications cause bone loss and we just don't know why.
Glucocorticosteroids (prednisone, prednisolone, cortisone, glucocorticoids, steroids, adrenocorticotropic hormone [ACTH], Orapred®, Pediapred®, Prelone®) are the main group of medications associated with secondary osteoporosis. They cause more osteoporosis than any other medication. The glucocorticosteroids, also called corticosteroids or more commonly just steroids, can be taken orally, inhaled, injected, or used topically (through the skin) or intravenously. The oral, intravenous, and injected forms of steroids are the most damaging to bones. The long-term effects of inhaled or topical steroids on bone have not been well studied, so are not as well understood. Steroids are most often used in the treatment of asthma and other chronic lung diseases such as cystic fibrosis, emphysema, and sarcoidosis; rheumatologic disorders such as rheumatoid arthritis and lupus; skin diseases such as psoriasis and eczema; and inflammatory bowel diseases such as Crohn's and ulcerative colitis. Steroid (glucocorticoid) medications can cause osteoporosis for several reasons. First, they interfere with calcium absorption from food. Second, they may increase the amount of calcium lost through the kidneys. Third, they interfere directly with bone formation and with the production of testosterone and estrogen, which are hormones necessary for bone formation. And last, steroids can interfere with the ability to perform bone-strengthening exercises and increase fracture risk by causing muscle weakness and exercise intolerance.
Glucocorticoid-induced osteoporosis (GIO) can occur with as little as 3 months of treatment. If you are treated for longer than 6 months, you have a 50% chance of developing osteoporosis. And if you are treated long-term, you also have a 50% chance of sustaining a fracture related to osteoporosis. Doses at or above 5 mg per day are believed to stop new bone formation, causing rapid bone loss (see Question 88). Several medications used to treat osteoporosis and osteopenia carry an indication for use in patients taking long-term steroids at doses at or above 7.5 mg per day. Many clinicians will start therapy even if the steroid dose is 5 mg per day to slow or prevent additional bone loss (see Question 55).
The long-term use of the following medications also puts you at greater risk for osteoporosis:
• Levothyroxine (such as Synthroid®, Levathroid®, Unithyroid®, Levoxyl®, Eltroxin®) is used in the treatment of hypothyroidism (underactive thyroid gland).
• Anticonvulsants (such as Dilantin® [phenytoin]; phenobarbitol; Tegretol®, Carbatrol® [carbamazepine]; Depakote® [divalproex]; Depacon® [valproate]) are used in the treatment of seizure disorders.
• Methotrexate is used in the treatment of certain cancers and some chronic conditions such as rheumatoid arthritis and psoriasis.
• Heparin® and Coumadin® (warfarin) are used to prevent or dissolve blood clots resulting from immobility, pulmonary embolism, venous thrombosis, or atrial fibrillation.
• Lithium (Lithobid®, Eskalith®) is used in the treatment of manic depression (bipolar disorder), mania, and schizoaffective disorders.
• Gonadotropin-releasing hormone agonists (GnRHa) (such as Lupron or its generic equivalent, leuprolide acetate) are used to reduce estrogen levels in premenopausal women with endometriosis and fibroids; they are also used to reduce testosterone levels in men with prostate cancer. Because GnRHa reduces both estrogen and testosterone levels, it has a damaging effect on bone and is usually prescribed for only 3 to 6 months at a time. Bone density is closely monitored if it is used for longer periods.
• Antacids containing aluminum (such as Amphogel®, Maalox®, Mylanta®) are used in the treatment of indigestion. Some clinicians advise switching to a nonaluminum-containing antacid, such as Tums®, Di-Gel®, or Rolaids®, if you need to use antacids long-term. A list of antacids and their contents can be accessed through a Web site provided in Appendix B.
• Medroxyprogesterone acetate injection (Depo-Provera® contraceptive injection) is usually used as birth control in women. Recently, the FDA announced that it was mandating a label change to highlight the risk of bone loss with prolonged use (i.e., > 2 years) of Depo-Provera. It is not clear if the loss is reversible when the every-3-months injections are stopped, but prior research with postmenopausal women indicated that previous use of Depo-Provera did not have an effect on bone density after menopause, and more recent research with adolescent girls showed that bone density was preserved if they also took estrogen supplements while on the Depo-Provera.
• Proton pump inhibitors (Aciphex®, Nexium®, Prevacid®, Prilosec®, Prilosec OTC®, Protonix®, Zegerid®) are used to treat acid reflux and ulcers.
• Selective seratonin reuptake inhibitors (SSRIs) (such as Paxil®, Prozac®, Zoloft®, and others) are used to treat depression.
• Thiazolidinedione (TZD) (Actos®, Avandia®) is used to treat diabetes.
If you are taking or using any of these medications, you should have a discussion with your clinician about possible substitutes that would be equally as effective for treating your condition but would not jeopardize your bone health. You might also discuss having your bone health monitored and taking medications intended to treat and prevent further bone loss (see Questions 23-25, and 55).
You may also be taking medications that can actually improve your bone health. If you are taking estrogen either alone or in combination with a progestin for the treatment of menopausal symptoms, your bones will benefit and you can expect to have less bone loss (see Question 64).
If you are one of more than 8 million people taking statins (e.g., Mevacor®, Zocor®, Lipitor®) to lower your cholesterol, you may have the added benefit of improving your bone density and reducing your risk of fractures. Through an unknown mechanism, statins increase the levels of a bone-forming protein. Some studies have shown that statins can reduce the risk of hip fractures by as much as 30%. Other studies do not link statin use with a decreased risk of fracture and suggest that further study of the relationship between statins and bone health is needed. Although they may increase bone density, statins are not used to treat or prevent osteoporosis.
If you are taking a thiazide diuretic, such as Diuril®, Aquazide®, hydrochlorothiazide (HCTZ), and Esidrix®, to lower your blood pressure, you may be preventing bone loss, at least while you're taking it. Thiazide diuretics decrease the amount of calcium you lose through your kidneys and therefore increase the amount of calcium your body has available for bone formation. Although not prescribed for osteoporosis treatment or prevention, this class of medications also substantially cuts the risk of osteoporosis-related fractures. Once the medication is stopped, however, the benefits to bone health stop as well.