Fosamax Hair and Skin Changes: What Alendronate Actually Does to Integument

Does alendronate cause hair loss?

Whether alendronate can cause hair loss is not established, and how often it might happen is unknown.

Diffuse shedding has other possible causes. Telogen effluvium, the abrupt shedding of normal club hairs, is the most common cause of diffuse hair loss in adult women [3]. This is general background on hair loss and has not been tied to alendronate. It may begin 2 to 3 months after a trigger such as childbirth, high fever or major surgery, and usually resolves within 3 to 6 months if the trigger is removed or treated [3]. When diffuse hair loss has no clear cause, checking ferritin and thyroid function may help identify iron deficiency or a thyroid disorder, which often show no other obvious features [3]. Gradual thinning with a widening central part fits female pattern hair loss [3].

What the label says about skin reactions

The adverse reactions section states that rash and erythema have occurred [1]. Hypersensitivity to any component of Fosamax is a contraindication, and reported reactions include urticaria and angioedema [1]. No frequency is given for any of these.

If you notice a rash or shedding

Hives or angioedema (swelling) need urgent medical care, because the label says Fosamax should not be used by anyone with hypersensitivity to any of its components [1]. Tell your prescriber about any new rash or shedding. For shedding, timing is the useful clue: loss that begins 2 to 3 months after a new medication or illness and then settles fits telogen effluvium, while gradual thinning with a widening central part fits female pattern hair loss [3].