Disclosed is a pharmaceutical dosage form for administration twice daily, once daily or less frequently, which contains 6-fluoro-(N-methyl- or N,N-dimethyl)-4-phenyl-4,9-dihydro-3H-spiro[cyclohexane-1,1-pyrano[3,4,b]indol]-4-amine represented by formula (I) or a physiologically acceptable salt thereof, and a surfactant. The pharmaceutical dosage form is intended for treating pain selected from acute, visceral, neuropathic or chronic pain. Also disclosed is the use of the dosage form for the manufacture of a medicament for the treatment of pain.
