Viagra is blue. Nexium is purple. Those color schemes have been integral to the drugs’ marketing, and thus their sales, and thus the billions of dollars they’ve made for their manufacturers. And those colors weren’t an accident.

“We typically select a brand’s colors palette and logo years before launch, based on deep customer insights," Eli Lilly told BioPharma Dive for this thorough exploration of the color-selection process.

Several factors affect drugmakers’ dye decisions, according to the report:

• Drugmakers don’t want their products to be the same color as competing products.
• The color of the pill itself integrates into the drug’s overall marketing scheme.
• Regulatory requirements limit certain ingredients, which limits color options.
• Different colors have different meanings in different parts of the world.
• As with any other design choice, colors like red and orange suggest stimulus, while shades of blue imply serenity. So the color depends on what the drug does.

"If you have a product for, let's just say a dermatology product for psoriasis, you're not going to make the color red because that reminds people of inflammation. You're not going to use the color yellow for something treating an infection because that reminds you of pus," Dave Traini, the creative director at a health care advertising agency, told BioPharma Dive.