by Fabiana Banov, RPh, MS, PCCA Senior Formulation Pharmacist

Our formulation development lab is dedicated to creating new formulas for our members. We deal with daily challenges, just like a regular compounding pharmacy does. Some formulas are very difficult to work with, need researching, chemical knowledge and diligence to create a quality preparation. The work is done when we decide which is the best version to offer to our members. It doesn’t matter the time or the number of versions we need to complete the task.

We recently received a request to develop compounded oral suspensions using two very difficult-to-mask, bitter active pharmaceutical ingredients (APIs). We decided that it was necessary to use all the flavor and sweetening techniques to adjust the final taste in a way that the patient would find acceptable.

The two formulas are

1. PCCA Formula #14374 – Acetaminophen* 325 mg/5 mL Oral Suspension (SuspendIt®)

2. PCCA Formula #14385 – Acebutolol 100 mg/mL Oral Suspension (SuspendIt)

These formulas utilize PCCA SuspendIt (PCCA #30-4825), an oral suspension base that is naturally sweetened with monk fruit, which aids in the ability to help mask the undesirable taste of some active ingredients.

*Note: The concentration of over-the-counter liquid acetaminophen products is 160 mg/5 mL so use caution in dosing.

The first step that we always need to follow when masking bitter APIs is to create a solid foundation using a combination of sweeteners. This will help create a “barrier” for the taste buds, where the bitterness will be masked and the flavor enhanced. The number of sweeteners is evaluated based on the level of bitterness of the formulation.

PCCA FORMULA #14374 – ACETAMINOPHEN 325 MG/5 ML ORAL SUSPENSION (SUSPENDIT)

In this case, the combination of Steviol Glycosides 95% (PCCA #30-4539) and Acesulfame Potassium FCC (PCCA #30-4398) at 0.4% each was enough to mask the bitterness of the API. Then, we need to finally think about the flavors that would be used. For bitter APIs, one flavor option is usually not enough. A combination of two or more flavors will create a better composition of notes and the final taste of the medication will be more palatable. Here we used Banana Creme, Artificial (PCCA #30-2169) at 1% and Caramel, Artificial (PCCA #30-2163) at 2%. Together, they make the preparation sweet and deliver a nice final taste in the mouth.

PCCA FORMULA #14385 – ACEBUTOLOL 100 MG/ML ORAL SUSPENSION (SUSPENDIT)

This was a different story, since acebutolol is an extremely bitter API and very hard to mask. In this case, a combination of three sweeteners was necessary to mask the bitterness. The formula uses Steviol Glycosides 95% and Acesulfame Potassium FCC at 0.6% each, along with Magnasweet 110® (Liquid) (PCCA #30-2628) at 0.5%. After many flavor trials, the combination of Grape Colorless Artificial (PCCA #30-4908) and Marshmallow, Artificial (PCCA #30-2699), each at 2%, created a palatable preparation.

Another combination of flavors that is an acceptable option for this API is:

Raspberry Powder, Artificial (PCCA #30-3272) at 3% and Marshmallow, Artificial at 2% along with Crème deMenthe (PCCA #30-2327) at 0.5%. This combination can be used for patients who prefer a more minty taste in their preparation.

A FLAVOR TIP

Caramel or marshmallow are a great addition for masking bitter APIs. Their mild creamy tastes promote and complement other flavors used in the formulations.

Flavoring is an art and the more you know, the better your formulation will taste. PCCA members with clinical services may contact the Clinical Services team for help with flavoring and other compounding concerns.

A version of this article originally appeared entirely in PCCA’s members-only magazine, the Apothagram.