Can Amazon-like reviews work for prescriptions?

When American consumers shop for clothes, cars and electronics, there's a simple process they often use to start their search: star ratings. But when it comes to prescription drugs, patients are typically in the dark, often guided by the advice of a single doctor.

A start-up called HealthTap is out to change that. Founded five years ago to provide consumers with better health information online through an expansive network of doctors, HealthTap on Wednesday introduced RateRx, which is designed to provide free ratings on prescription medications.

It works like this. A patient is prescribed Amoxicillin to treat an ear infection. Rather than simply calling the neighborhood Walgreens to order the medication, the patient can first launch the HealthTap app and type in the drug's name. Up will pop a five-star review system, with ratings and commentary from doctors on whether the drug is the best treatment for the ailment and what some alternatives may be.

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"We need to empower people to make better decisions," said Ron Gutman, founder and chief executive officer of HealthTap in Palo Alto, California. RateRx is "super useful and it's transparent."

HealthTap is able to solicit expert advice from a sufficient sample of doctors because it has 67,000 in its network. The app originally caught on with moms and pregnant women by letting them ask specific questions to obstetricians, gynecologists and pediatricians and get better answers than they could from sources like WebMD or just by searching Google.

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The service then opened up to all doctors and expanded from a question and answer service to one that allows one-to-one communication between patient and doctor on a protected site.

For RateRx, HealthTap invited more than 567,000 doctors to participate, including those in its network plus an additional 500,000. According to HealthTap, ratings have been compiled for thousands of medications for conditions like acne, arthritis, anxiety, diabetes, headaches and hypertension.

HealthTap has raised about $38 million in venture funding from investors including Mohr Davidow Ventures, Mayfield Fund, Khosla Ventures and Google Chairman Eric Schmidt.