The invention relates to a 
content determination method for 
coleus forskohlii capsules. The method adopts 
high performance liquid chromatography, and includes the steps of: 1. weighing an isoforskolin reference substance, adding 
methanol to prepare a solution with a content of 0.1-0.3mg / ml; 2. taking 
coleus forskohlii capsules, pouring out the contents, mixing the contents evenly, taking 1 part of the mixture, adding 30-100 parts of 
ethanol, conducting ultrasonic treatment (or 
backflow, soxhlet extraction), performing 
filtration, taking subsequent filtrate, carrying out 
evaporation to 
dryness, or not using the aforementioned extraction method, adding 2-4 parts of 
silica gel and 5-7 parts of 
ethanol, blending the substances evenly, carrying out 
evaporation to 
dryness, 
grinding the substances evenly, then transferring the substances to a 
silica gel column, employing 120-180 parts of a 
petroleum ether-
ethyl acetate mixed solution in a volume ratio of 3:1 to perform 
elution, collecting the eluent, transferring the eluent to a 
silica gel column containing 3-8 parts of 2-4% AgNO3, discarding the 
effluent, using a 
mixed solution of 
petroleum ether and 
ethyl acetate in a volume ratio of 2:1 to perform 
elution, discarding the eluent, then using 90-180 parts of a 
mixed solution of 
petroleum ether and 
ethyl acetate in a volume ratio of 3:1 to perform 
elution, collecting the eluent, conducting 
evaporation to 
dryness, performing 
dissolution with 
methanol, and transferring the product into a 2-5 times measuring flask, adding 
methanol to scale, and performing 
filtration; and 3. sucking 5-20microl of the reference substance solution and the 
test solution respectively, injecting the solutions into a liquid chromatograph to obtain a chromatogram, and calculating the content of the effective component isoforskolin in the 
test solution according to the chromatogram.