@iamnana
There is no listed side effect that gabapentin causes osteoporosis however seizure medicines, which I have been on for about 60 years, especially on high doses can indeed cause osteoporosis which I have. Possibly because I used to take Five different seizure medications and 30 pills a day So I'm not surprised I have osteoporosis, especially since I did in fact, take high doses of all the seizure medicines I was on. Gabapentin is 30 years old. Some say it's an older drug some say it's a newer drug Even though it more than 17 years old. I would consider it to be a newer drug myself. Personally, I wouldn't worry about osteoporosis if you were taking gabapentin or Lyrica and not taking a high dose or taking other seizure medications along with it. However, I think the best thing to do would be to contact your doctor. Also, most antiseizure medications are definitely associated to a higher risk of fractures, regardless of whether or not you have osteoporosis. That may be associated with the fact that people with seizures fall so frequently or have other types of accidents.
Another concern with older seizure medications is how it affects Vitamin D need for bones.
Most Antiseizure medication's increase levels of chemicals in the liver that destroy vitamin D, which the body needs to absorb calcium.
You might also ask a dietitian or a pharmacist.
Good luck,
Jake