RK-851 is a highly selective and orally active δ-opioid receptor antagonist, with a negative logarithm of the antagonist concentration (pA2) of 8.84. TRK-851 exhibits the selectivity for the δ receptor of more than 100 times higher than that for the μ or κ receptors. TRK-851 exhibits a potent antitussive effect in a rat model of capsaicin-induced cough. TRK-851 can be used for research on antitussive effects.

Providing storage is as stated on the product vial and the vial is kept tightly sealed, the product can be stored for up to 24 months.
Wherever possible, you should prepare and use solutions on the same day. However, if you need to make up stock solutions in advance, we recommend that you store the solution as aliquots in tightly sealed vials at -20°C. Generally, these will be useable for up to one month. Before use, and prior to opening the vial we recommend that you allow your product to equilibrate to room temperature for at least 1 hour.