Question

Case #4 AP is a 34-year-old male that presented to the ambulatory care clinic. He had recently undergone a Roux-en-Y gastric bypass (5 weeks ago), but he is feeling well and has no complaints. His wife is with him today and claims that AP has been exhibiting seizure symptoms at home including staring off, "blanked face", and periods of fast blinking. The physician prescribed Depakote Delayed-Release: 3000mg/day (1500mg BID) and lisinopril 20mg/day When the prescription reached to pharmacist, he realized that he does not have the Lisinopril tablet on hand. Instead he has a stock solution of lisinopril 100 g/liter. He decided to take 10 mL of this stock solution made up to 120 mL with water and then took 5 mL of the second solution and made into a 100-mL elixir. Calculate the concentration of Lisinopril (%w/w) in the final elixir. The specific gravity of the elixir is 1.28.

Answer 1

Formula :Specific Gravity (SG) = Weight of substance / Weight of an equal volume of water

we need to find out weight of lisinopril in the final elixril. so weight of substance is (X),specific gravity is 1.28,volume of water is 100ml.

1.28=X / 100

X=1.28 /100

X=0.0128gm

so the concentration  of lisinopril is the solution is 0.0128gms.