Surge in Cipro prescriptions worries physicians who say drug can have serious side effects.(Chicago Tribune)

Although Cipro has emerged as the treatment of choice for suspected cases of anthrax, a nationwide surge in prescriptions for the drug worries physicians who say the antibiotic can have serious side effects, particularly among young people and pregnant women.

Outbreaks of anthrax, borne by spores in envelopes mailed to government offices and media outlets in south Florida, New York and Washington D.C., have triggered a predictable spike in Cipro sales in the affected regions. But physicians in areas untouched by anthrax also are reaching for the prescription pad.

"There's been a 20 to 25 percent increase in utilization since the first of October," said Raulo S. Frear, vice president of clinical services for Express Scripts of St. Louis, one of the nation's largest pharmacy …