Encompassed are pharmaceutically acceptable compositions formulated for the topical or transdermal delivery of probes specific for cyclooxygenase-2 (COX-2) of human and non-human subjects. In particular, an activatable probe comprises a fluorescent moiety comprising a fluorophore attached to a compound having selective affinity for COX-2, and a removable fluorescence quencher linked to the fluorescent moiety by a cleavable linker. Upon delivery to a recipient subject, the activatable probe is localized and concentrated in tissues and cells with elevated levels of COX-2. The linker is cleaved to release the fluorescence quencher. Irradiation by an activating incident illumination results in a detectable fluorescent emission signal
