Adverse effects
In October 2020, the U.S. Food and Drug Administration (FDA) required the drug label to be updated for all nonsteroidal anti-inflammatory medications to describe the risk of kidney problems in fetuses that result in low amniotic fluid. They recommend avoiding NSAIDs in pregnant women at 20 weeks or later in pregnancy. Mechanism
Ketoprofen undergoes metabolism in the liver via conjugation with glucuronic acid (glucuronidation) by UGT enzymes, hydroxylation of the benzoyl ring by the CYP3A4 and CYP2C9 enzymes, and reduction of its ketone moiety (a carbonyl functional group, i.e. with carbon-oxygen double bond) by carbonyl reducing enzymes (CREs). Ketoprofen is used for its antipyretic, analgesic, and anti-inflammatory properties by inhibiting cyclooxygenase-1 and -2 (COX-1 and COX-2) enzymes reversibly, which decreases production of proinflammatory prostaglandin precursors.The patches have been shown to provide rapid and sustained delivery to underlying tissues without significantly increasing levels of drug concentration in the blood when compared to the traditional oral administration. Chirality and biological activity
Ketoprofen has one stereogenic center in the side chain and hence exists as mirror-image twins. Majority of the profens are marketed as racemic mixtures. For most of the NSAIDs the pharmacological activity reside in the (S)-enantiomers with their  (R)-enantiomer of virtually inactive. An interesting observation about most profens including ketoprofen is that they undergo unidirectional metabolic inversion, chiral inversion, of the (R)- acid to its (S)-mirror-image version with no other change in the molecule.
Impact in the United States
M. cerebralis was first recorded in North America in 1956 in Pennsylvania, having been introduced via infected trout imported from Europe, and has spread steadily south and westwards. Until the 1990s, whirling disease was considered a manageable problem affecting rainbow trout in hatcheries. However, it has recently become established in natural waters of the Rocky Mountain states (Colorado, Wyoming, Utah, Montana, Idaho, New Mexico), where it is causing heavy mortalities in several sportfishing rivers. Some streams in the western United States have lost 90% of their trout. In addition, whirling disease threatens recreational fishing, which is important for the tourism industry, a key component of the economies of some U.S. western states. For example, "the Montana Whirling Disease Task Force estimated trout fishing generated US $300,000,000 in recreational expenditures in Montana alone". Making matters worse, some of the fish species that M. cerebralis infects (bull trout, cutthroat trout, and steelhead) are already threatened or endangered, and the parasite could worsen their already precarious situations. For reasons that are poorly understood, but probably have to do with environmental conditions, the impact on infected fish has been greatest in Colorado and Montana, and least in California, Michigan, and New York. Impact in Canada
Whirling disease was first detected in fish in Johnson Lake in Banff National Park in May, 2016. CFIA Labs confirmed in August and Parks Canada announced the outbreak August 23, 2016. Although it was first discovered in Banff, it is not necessarily where the disease originated and spread.