The present discovery pertains generally to the field of therapeutic compounds. More specifically the present discovery pertains to certain di-isopropyl-phosphinoyl-alkanes as described herein, DIPA-1-5, DIPA-1-6, DIPA-1-7, DIPA-1-8, and DIPA-1-9, collectively referred to herein as “DIPA compounds”, that are useful, for example, in the treatment of disorders (e.g., diseases) including: sensory discomfort (e.g., caused by irritation, itch, or pain); a skin dysesthesia; dermatitis; ocular pain and discomfort; heat discomfort; heat stress; flushing and / or night sweats (vasomotor symptoms); post-operative hypothermia; post-anaesthetic shivering; fatigue; tiredness; depression; cognitive dysfunction; and to enhance cognitive function. The applicant has found that localized delivery of DIPA compounds to the upper eyelid and / or facial skin has an alerting and enhancement effect on behavior and can be used to give a cosmetic refreshing look, to mental alertness, to reduce fatigue, and to improve work output. The present discovery also pertains to pharmaceutical compositions comprising such compounds, and the use of such compounds and compositions, for example, in therapy, in diagnosis of neuropathic pain, and in study of TRPM8 function.