Hillary Clinton said she would give close scrutiny to health-insurance industry mergers like those proposed this year by Anthem Inc. and Aetna Inc., part of the Democratic presidential candidate’s latest policy plans.

Clinton’s campaign, which on Tuesday released a group of policies that would lower Americans’ prescription drug spending, said Wednesday that she would give families tax credits worth as much as $5,000 to help pay for all out-of-pocket health-care costs, while individuals would get as much as $2,500.

The credit would be available for those who spend in excess of 5 percent of their income on health care, and would be paid for by “demanding rebates from drug manufacturers and asking the most fortunate to pay their fair share,” her campaign said. Clinton’s drug cost proposal caused a slide in health-care stocks on Monday, sending the Nasdaq Biotechnology Index down 4.4 percent after she said on Twitter that she would release a plan.

She also called for health insurance reforms that build on what’s already in the Affordable Care Act, also known as Obamacare.

“When Americans get sick, high costs shouldn’t prevent them from getting better,” Clinton said in a statement. “With deductibles rising so much faster than incomes, we must act to reduce the out-of-pocket costs families face. My plan would take a number of steps to ease the burden of medical expenses and protect health-care consumers.”

The campaign cited a report released this week by the Kaiser Family Foundation that showed patient deductibles were rising faster than the cost of buying health coverage.

Clinton’s campaign also promised to “vigorously enforce antitrust laws to scrutinize mergers and ensure they do not harm consumers,” mentioning insurers as well as doctors and hospitals that sell them services.

Health Mergers

Deals announced this year will consolidate the health insurance industry’s top five companies into three. In July, Anthem agreed to buy Cigna Corp. for about $48 billion, and Aetna struck a $35 billion deal for Humana Inc. Anthem’s and Aetna’s chief executive officers told lawmakers Tuesday that the deals would benefit consumers and are necessary to succeed in a changing health-care landscape.

Clinton would also create a process for states that don’t have the authority to block or modify health insurance premium increases to stop what the campaign called “unreasonable” rises in rates.