Topiramate, or Topamax, is a drug called an anticonvulsant that is used to prevent seizures. It is used alone in adults and children age 10 or older and may also be used in combination with other drugs. Topamax is also used in adults to prevent --- but not treat --- migraine headaches. The drug will not stop a migraine that has already begun. Like all drugs, Topamax has side effects, and two of those are related to kidney stones.
Kidney Stones
Kidney stones, according to the Mayo Clinic, form inside the kidneys when the urine becomes concentrated and allows minerals to stick together. The resulting crystals become a hard mass that must then be passed out of the kidney into the bladder. Kidney stones can cause severe pain and may be accompanied by chills, fever, nausea and vomiting. Although kidney stones do not usually cause permanent damage, they tend to recur.
Topamax Side Effects
Topamax side effects are varied. A few people on Topamax have developed an eye condition similar to glaucoma. Topamax can also cause inadequate sweating, causing the body temperature to rise dangerously high. Metabolic acidosis is another side effect that is a problem in its own right and may increase the risk of kidney stones. Acidosis is a condition in which the blood becomes too acidic. Up to two-thirds of children and one-third of adults will develop metabolic acidosis while taking Topamax.
Topamax and Kidney Stones
Kidney stones have occurred in in about 1 in 50 adults taking Topamax. Men and those who have previously had kidney stones are more likely to develop kidney stones while on Topamax. Some drugs, such as Diamox and Zonegran, increase the risk of having a kidney stone while taking Topamax. A diet called the ketogenic diet, which is sometimes used in children to help prevent seizures, can also increase the risk of kidney stones if the patient is taking Topamax while on the ketogenic diet.
Considerations and Warnings
Some strategies can help prevent kidney stones, especially calcium stones. The Mayo Clinic recommends you drink enough water to pass 2.6 quarts of urine each day if you have had a kidney stone and says you may also want to drink black or green tea with lemon. Eat fewer high-oxalate foods, as calcium oxalate stones are the most common type. Reduce salt and animal protein intake, and use caution with calcium supplements. Do not just stop taking your Topamax, as you may increase your risk of seizures. If you have questions or concerns, consult a health care professional.
References
- Epilepsy.com; What are the Most Serious Side Effects of Topamax?: Basic; Steven C. Schachter, M.D.; July 2008
- Drugs.com; Topamax; March 2011
- Janssen Pharmaceuticals, Inc.; Topamax Important Safety Information; August 2011
- The Mayo Clinic: Kidney Stones: Alternative Medicine
- The Mayo Clinic: Kidney Stones: Definition
