| Mechanism of action |
The action of risedronate on bone tissue is based partly on its
affinity for hydroxyapatite, which is part of the mineral matrix of
bone. Risedronate also targets farnesyl pyrophosphate (FPP) synthase.
Nitrogen-containing bisphosphonates (such as pamidronate, alendronate,
risedronate, ibandronate and zoledronate) appear to act as analogues of
isoprenoid diphosphate lipids, thereby inhibiting FPP synthase, an
enzyme in the mevalonate pathway. Inhibition of this enzyme in
osteoclasts prevents the biosynthesis of isoprenoid lipids (FPP and
GGPP) that are essential for the post-translational farnesylation and
geranylgeranylation of small GTPase signalling proteins. This activity
inhibits osteoclast activity and reduces bone resorption and turnover.
In postmenopausal women, it reduces the elevated rate of bone turnover,
leading to, on average, a net gain in bone mass. |
| Toxicity |
Side effects include abdominal pain, anxiety, back pain, belching,
bladder irritation, bone disorders and pain, bronchitis, bursitis,
cataracts, chest pain, colitis, constipation, depression, diarrhea,
difficulty breathing, dizziness, dry eyes, eye infection, flu-like
symptoms, gas, headache, high blood pressure, infection, insomnia,
itching, joint disorders and pain, leg cramps, muscle pain, muscle
weakness, nausea, neck pain, nerve pain, pain, pneumonia, rash, ringing
in ears, sinus problems, sore throat, stomach bleeding, stuffy or runny
nose, swelling, tendon problems, tumor, ulcers, urinary tract infection,
vertigo, vision problems, and weakness. |
