Eli Lilly is the powerhouse behind today’s blockbuster drugs Mounjaro (tirzepatide), prescribed for weight loss; erectile-dysfunction treatment Cialis (tadalafil); Humalog, a rapid-acting insulin; and diabetes treatment Trulicity. Founded in 1876 by Civil War veteran Eli Lilly, it was the first to mass-produce insulin in the 1920s, one of the first to mass-produce penicillin during World War II, and an early producer of the polio vaccine. The company has also developed several major mental-health drugs, including Prozac (fluoxetine), one of the most widely prescribed selective serotonin reuptake inhibitors in the world. Eli Lilly operates in over 100 countries.

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