WASHINGTON — The sick, poor and elderly who need prescriptions would suffer from a bill that would extend patents on seven drugs, a former senator who represents consumer groups said Wednesday.

Howard Metzenbaum of the Consumer Federation of America said the legislation would block manufacturers of generic drugs from making cheaper versions of brand-name medicines. “The bill is essentially a tax on the uninsured, the poor, the sick and the elderly,” Metzenbaum, a former Democratic senator from Ohio, told the Senate Judiciary Committee. “I strongly urge you to reject it.”