Question

a pharmacy technician is preparing a 0.2% hydrocortisone ointment, but the pharmacy only has 2.5% hydrocortisone ointment available. which of the following should the technician use to dilute the ointment?
○ 3% hydrocortisone ointment
○ petroleum jelly
○ water
○ 1% hydrocortisone ointment

question 29
1 point
a pharmacy technician is preparing a prescription for a mouthwash that contains a 1:2:1 ratio of diphenhydramine, lidocaine, and aluminum hydroxide. if the solution contains 60 ml of lidocaine, how many ml of diphenhydramine should the technician compound?

Explanation:

First Question (Dilution of Ointment)

To dilute a 2.5% hydrocortisone ointment to 0.2%, we need a diluent with no hydrocortisone (or a lower concentration, but a non - active diluent is standard for ointments). 3% and 1% hydrocortisone ointments would increase or not sufficiently dilute the concentration. Water is not suitable for diluting ointments (ointments are oil - based or semi - solid, water is aqueous). Petroleum jelly is an inert ointment base, so it can be used to dilute the hydrocortisone ointment.

Step1: Understand the ratio

The ratio of diphenhydramine:lidocaine:aluminum hydroxide is \(1:2:1\). Let the volume of diphenhydramine be \(x\), lidocaine be \(2x\) (since the ratio of diphenhydramine to lidocaine is \(1:2\)) and aluminum hydroxide be \(x\).

Step2: Solve for \(x\)

We know that the volume of lidocaine is 60 mL, and from the ratio, the volume of lidocaine is \(2x\). So we set up the equation \(2x = 60\).
To find \(x\), we divide both sides of the equation by 2: \(x=\frac{60}{2}=30\).

Answer:

B. Petroleum jelly

Second Question (Ratio Calculation)