From The Trademark Blog:
Plainitff Shire manufactures and sells ADDERALL which is prescribed for ADHD. It moved to enjoin defendant Barr Lab's generic alternative on the grounds that it infringed Shire's trade dress in the shape and color of the pill. The Third Circuit affirmed the refsual of the motion for preliminary injunction because Shire did not establish that its trade dress was non-functional. The case has a thorough discussion of the functionality of color in medication.