The trade deal reached between the United States and the European Union on Sunday will impose a 15 percent tariff on imported medicines from Europe. Drugmakers manufacture some of their biggest and best-known blockbusters there, including Botox, the cancer medication Keytruda and popular weight-loss drugs like Ozempic.

The tariff rate is much lower than the levies of up to 200 percent that President Trump had threatened. Still, the new import costs stand to add billions of dollars in expenses for the drug industry and could lead to price increases for some medicines. That could translate into higher out-of-pocket costs and higher health insurance premiums for Americans.

The 15 percent rate is final and will not be affected by the national-security-related tariffs that Mr. Trump is expected to impose on pharmaceuticals made elsewhere in the world, according to a White House official and senior European Commission officials. This outcome is something of a win for the pharmaceutical industry, which had feared that drugs from Europe would be hit with high levies related to national security. Both sets of pharma tariffs are expected to take effect simultaneously sometime next month, officials said.

The pharmaceutical industry depends on a complex global supply chain: Production of most medications happens in multiple countries, with plants around the world handling different stages of the process. Europe is perhaps the most important piece of the global network that produces brand-name drugs — those with patent protection and typically high prices and fat profit margins.

Pharmaceutical products are Europe’s No. 1 export to the United States. European officials have expressed worries in recent months that pharma tariffs could prompt drugmakers to pull back on investments, at the expense of jobs, factories and tax revenue.

Ireland in particular has become a pharma manufacturing hub, in part because doing business there helps drug companies lower their overall tax bills. Nearly all of the largest drugmakers have factories there. Last year, Ireland sent the United States $50 billion worth of pharma products, most of which were made by multinational drug companies.