Question

1. Children’s Tylenol is available as a 160 mg/5mL suspension. However, a parent with a 6- year-old diabetic child with a dye allergy has brought in a prescription for compounding a similar suspension.

Acetaminophen 160 mg/5 mL Sugar-free syrup qs ad 120 mL M.ft. susp. Would you recommend the parent to purchase the OTC product rather than the compounded preparation?

Explain your answer.

2. While preparing the suspension, you notice that the sedimentation rate was too high, what could be done to slow down the rate?

3. Why should the powders be levigated with a small amount of the suspending vehicle prior to bringing the suspension to the desired volume?

4. What can happen to the compounded preparation if the drug powder is not thoroughly "wet" prior to vehicle incorporation?

5. Can the "suspending" agent be used as the wetting agent? Explain your answer.

Answer 1

Ans.1) Yes, in certain situation, i recommend the parent to purchase the OTC product rather than the compounded preparation. The mentioned patient i.e., a 6- year-old diabetic child. Acetaminophen 160 mg/5 mL is a sugar-free syrup qs ad 120 mL M.ft. susp, hence i recommend it in this situation.

2.) Stability of a suspension is solely dependent on the sedimentation rate of dispersed phase, which is dependent on the viscosity of the dispersion medium. Reduce the viscosity , it eventually slow down the sedimentation rate.

3.) The powders be levigated with a small amount of the suspending vehicle prior to bringing the suspension to the desired volume to make the resulting suspension homogenous,

4.) If the drug powder is not thoroughly wet prior to vehicle incorporation the suspension will not be homogeneous dispersion and uniform. The powder must be wet before it is added into the vehicle. Following wetting of the powder, the liquid vehicle should be added in portions with trituration until a smooth, uniform preparation is formed. To ensure the complete transfer of the suspended ingredient, the compounder should use some of the remaining vehicle to rinse the material from the mortar into the dispensing container. Finally, sufficient vehicle is added to make the preparation of the desired volume.

5.) In a pharmaceutical suspension, a suspending agent helps the drug stay in the body of your suspension thereby preventing caking at the bottom. Whereas, wetting agent is a chemical agent which is capable of reducing the surface tension of a liquid in which it is dissolved.