How do I prepare a 5 mg/ml prednisolone mixture?

Which ointment base should be used for this ointment with such high concentrations of revulsives, containing 10 g menthol, 4 g camphor, and 30 g methyl salicylate with ointment base up to 100 g?

Can propylene glycol be used as a solvent for nipa esters in aqua conservans for use in syrups?

Can HPMC and HEC be used interchangeably in a neutral lubricating gel, and if so, in what ratio; does one offer specific advantages over the other, and what is the stability or shelf life of such a gel?

With which product can tragacanth be replaced in a prescription consisting of 25 mg prednisolone disodium sulfate, 12 drops of opium tincture, 0.8 g tragacanth, 12 g sulfaguanidine, 15 g 5-aminosalicylic acid, and water up to 300 cc, with instructions for a 40 ml enema in the evening?

What is the ideal preparation method for a solution containing 17.5 g salicylic acid, 5 g acetone, and ricinated collodion up to 50 ml, given that the salicylic acid is very difficult to dissolve and forms a thick paste after cooling if heat is used?

What are the stability problems of a solution containing 3 grams of Phenobarbital sodium and purified water up to 300 cc?