What are Bulk Ingredients and Why are they Necessary for Compounding?

When a medical practitioner determines that a medication needs to be compounded to meet the needs of patients ... 

... it is because there is no commercially available, FDA- approved medication to fit that patient’s medical need. While there may be commercially available FDA-approved medications containing the active ingredient being prescribed, the dosage form, strength or flavor of the medication may be one that the patient physically cannot tolerate. In other cases, excipients such as fillers and preservatives found within the commercially available medication may prohibit the patient from being able to take the medication due to sensitivities or allergies to these substances.  

When a drug is customized, or compounded, to meet the identified needs of patients or groups of patients, it is common practice to use only ingredients necessary to achieve the prescribed compounded medication. This means starting with the active pharmaceutical ingredients (API) in its purist form, and then adding only the excipients necessary to achieve the prescribed dosage-form, strength, and where specified, flavor. These are the essential ingredients that make the medicine what it is, and are commonly referred to as bulk ingredients. Using bulk ingredients in a compounded medication is the surest, safest way of satisfying the prescriber’s request for medication to meet the special, customized needs of the patient.

Replacing bulk ingredients used in compounds, particularly a bulk API, with an API from an existing commercially available medication, such as a tablet or capsule, has the potential for serious health problems for those patients using that medication, for two main reasons. First, because the active ingredient makes up only a small portion of the overall ingredients used in commercial tablets or capsules, it is impossible to separate the active ingredient from the other excipients (fillers, binders, dyes, flavorings, preservatives and other materials). Without being able to separate these excipients means that they would then become incorporated into the finished compounded medication.

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