Don’t know if this would work… But, how about mixing 1ml (20mg) of tadalafil suspension with enough powdered sugar to form a thick paste, then add into a 00 empty gelatin capsule? You can add enough confectioner’s sugar to approximate the volume of the empty 00 empty gelatin capsule. I imagine you can get the empty capsules online, if not, then find a cheap multi-vitamin or such that comes in a big capsule… empty the contents and replace it with the powdered sugar-tadalafil mix.
I’d try this myself, but the suspension I made is 20mg/5ml which would be too big of a volume for capsules.
I wouldn’t recommend this method, if the base of the suspension is water, rather than alcohol. Mixing water with sugar and putting into a capsule without preservatives would increase the risk of bacterial or mold growth.