Louis Théodore Frederic Colladon (25 August 1792 in Geneva – 25 April 1862) was a Swiss physician and botanist known for his investigations of the plant genus Cassia.
He was the son of pharmacist and amateur botanist Jean-Antoine Colladon (1755–1830).
He studied medicine at the University of Montpellier, where one of his instructors was botanist Augustin Pyramus de Candolle.
After graduation, he started a medical practice in Paris.
As a physician, he distinguished himself in the treatment of cholera patients during the epidemic of 1832.Among his written works was a monograph on Cassia titled "Histoire naturelle et médicale des casses, et particulièrement de la casse et des sénés employés en médecine" (1816) and a tale involving descent in a diving bell that was published in English as "Narrative of a descent in the diving-bell, &c.
&c." (Edinburgh : Printed for A.
Constable, 1821).
In 1830 the plant genus Colladonia was named in his honor by Augustin Pyramus de Candolle.