Pharmaceutical Compounding Calculations, Part Two–Bulk Drugs

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Performing calculations for the formulation of pharmaceutical dosage forms and related preparations is a key activity in compounding. Calculations provide the amount of drug specified in the medication order needed for compounding; it is the objective of the medication order. Correct drug calculations for compounded preparations are essential; if drug calculations are incorrect, the resulting preparation form will be incorrect, potentially with significant therapeutic and technical consequences.

Discussion topics

Part two of this series (click here for part one) addresses numeric calculations for types of bulk drugs. It builds on drug calculations topics previously described (1), including guidance documents (2–5). Textbooks (6–8) have always provided the foundation for mathematical calculations; discussion herein reflects academic teaching and practice in multiple workplace settings and integrates basic principles and problem experiences. Concepts that are often omitted, confused, or otherwise misunderstood that affect the accuracy of calculations are addressed.

Part two discussion describes a simple medication order and demonstrates calculations and labeling for each bulk drug type. The medication order identifies the active moiety. Types of active moieties and their differences must be understood. Calculating the active moiety amount for compounding follows. The active moiety is provided in the medication order by a proprietary or generic name, but not necessarily a precise name. Active moiety calculations determine the drug amount needed to prepare the dosage form quantity. The importance of active moiety calculation must not be underestimated. Interpreting a confusing medication order and verifying its intent is a critical step prior to numeric calculations. After the active moiety amount is calculated, the drug molecule for compounding is selected. Each molecule type is different, has different dosing, and requires different calculations. Notations and drug types in this discussion are as follows.

Active moiety. The active moiety expressed in the medication order is identified as Drug Z. Drug Z represents a common or familiar drug name (e.g., diazepam, Plavix, codeine—proprietary or generic drug name) applicable to all of the drug types to be calculated.

Non-salts. These drugs comprise molecules with covalent bonds and other non-salt molecule bonds. The active moiety of a covalent drug is usually the entire drug molecule (i.e., active moiety is same as bulk drug). The non-salt drug noted in the following discussion is also identified as Drug Z.

Salts. These drugs comprise molecules with ionic bonds (e.g., sodium drug, potassium drug, drug hydrochloride, drug acetate, etc.). The active moiety is the drug-ion part of the salt molecule. The compounded product dosage strength reflects the amount of drug-ion and not the entire salt molecule amount. The salt drug noted in this discussion is identified as Drug ZA.

Policy-exception salts. These drugs are also salts that ionize. However, the drug moiety is dosed together—drug-ion with counterion. Policy-exception salts include simple salts (lithium carbonate, iron sulfate, potassium chloride, and other common intravenous additives); salts affecting absorption, distribution, metabolism, and excretion; drugs with clinically significant amounts of cations (sodium, potassium, magnesium, calcium); drugs affecting physiological acid-base balance; and drugs approved before 2013 with established dosages; these exceptions are specified in the United States Pharmacopeia (USP) salt policy. The policy-exception salt drug noted in this discussion is identified as Drug ZB.

Some active moieties may be available in multiple drug types (e.g., phenytoin and sodium phenytoin; codeine and codeine phosphate). Each drug type may have different pharmacologic effects on patients (9) and different physicochemical properties relevant to compounding (e.g., a sodium salt will be more water-soluble than an acid or base) (10). After the bulk drug is selected, calculations are executed. Values determined in calculations are used in compounding and are reported in labeling. Pharma industry and 503B outsourcing facilities are likely to use bulk drugs for large-scale compounding. Figure 1 illustrates the bulk drug compounding process; specific topics addressed in this discussion are highlighted in red.

Figure 1. Drug calculations process—bulk drug.

Calculations sequence

The following describes a structured sequence of expressions used in these calculations. Examples addressing calculations for three types of drugs (non-salts, salts, and policy-exception salts) are provided. The medication order is identical for each drug category in the following discussion. This enables direct comparison of calculated values and label statements. Drugs in mixtures are another form of drugs for compounding; calculations for drugs in mixtures will be addressed in part three of this series. The following describes four steps to accomplish required calculations.

1. Medication order. Drug calculations are based on the medication order.
2. Active moiety. The active moiety amount needed to prepare the required medication amount order is calculated.
3. Drug amount. The bulk drug amount needed to prepare the compounded dosage form is calculated. Molecule calculations and mole calculations are used if needed.
4. Labeling. Labeling is determined from the medication order and calculated drug amounts. Additional molecule calculations and mole calculations may be needed. Labeling for the primary and secondary labels are determined.

Equations

Active moiety amount calculations. Active moiety amount calculations determine the amount of active moiety required to fulfill the medication order; in turn, this value will be used to calculate the drug substance amount. Active moiety calculation values come from the medication order. Values may be expressed in grams, milligrams, micrograms, specific drug units (e.g., heparin units, nystatin units, insulin units, etc.), liters, milliliters, teaspoonfuls, ounces, ratio strength, parts, and numerous other measurement units (Figure 2). The number of dosage units may likewise be expressed in multiple ways (e.g., doses per day, doses at hourly intervals, at bedtime, number of capsules, ounces or liters of liquid dosage form, and many others). Units of measure will cancel if an equation is properly designed, leaving the equation amount objective. Expressing the unit of measure is a critical activity in the active moiety calculation; omitting units of measure in calculations (i.e., using a smartphone or other calculator without recording units of measure) is a common cause of calculation errors.

Figure 2. Active moiety calculations. Units of measure may include mL, mg/mL, mg/5 mL, mg/teaspoon, ounce, liter, milliliter, specific drug units, or other units of measure. Number of dosage units may be expressed in mL, 5 mL, teaspoons, ounces, capsules, doses per day, time interval, doses per day, and many others.

Molecule calculations. Molecule calculations may be needed to determine a drug-ion molecular mass (molecular weight [MW]) if not available in reference literature. Calculating the MW of a drug active moiety or bulk drug requires addition of the individual element atomic masses (AW)—not atomic numbers—of the drug-ion or bulk drug. The drug-ion MW may be significantly different from the drug MW (e.g., clopidogrel [Plavix] MW 321.9, and clopidogrel bisulfate MW 419.9). Some drug molecules contain multiple active moieties (e.g., one divalproex sodium molecule contains two valproic acid moieties). Waters of hydration, solvates, complexes, and other molecular components must be included in drug molecular weights (e.g., ampicillin is commercially available as either anhydrous or trihydrate). Figure 3 illustrates molecular weight calculations of clopidogrel molecules using the general summation equation ∑AW = MW, where AW = atomic weights and MW = molecular weight.

Figure 3. Molecule calculations.

Mole calculations. Mole calculations are needed to correlate salt-ion active moieties, salt drugs, and pharmaceutical alternatives. Calculations involving moles are critical for certain drugs. The mole equation includes drug gravimetric weight and molecular weight (Figure 4). Recall from general chemistry that chemical reactions are balanced based on moles of reactants and products; pharmacologic action has the same quantitative relationship. Pharmaceutical alternatives (e.g., codeine, codeine sulfate, and codeine phosphate) provide equivalent clinical activity based on equivalent molar amounts—not equivalent gravimetric weights. If pharmaceutical alternatives are used in compounding, mole calculations are utilized to provide equivalent dosages (e.g., metronidazole benzoate gravimetric dosage larger than metronidazole base dosage). Ephedrine, pseudoephedrine, and phenylpropanolamine consumer purchasing restrictions are determined by mole calculations (e.g., 3.6 grams of pseudoephedrine base [daily sale limit] is available in 146 pseudoephedrine hydrochloride 30 mg tablets) (11). The equation shown in Figure 4a demonstrates the general mole equation, while the equation shown in Figure 4b illustrates the active moiety-drug relationship for salt drugs; note n = number of drug ions per molecule.

Figure 4. Mole calculations.

Label. Compounded product labels must accurately reflect the content of a compounded dosage form. Labels are described as primary labels on the front of the compounded preparation container and secondary labels on the side panels. Accurate compounded product labeling requires attention to detail (i.e., labeling “codeine” is not the same as labeling “codeine phosphate”). The labeling of non-salt compounded preparations is straightforward; covalent active moieties are same as corresponding bulk drugs; the stated amount of drug must clearly identify the name and drug amount (e.g., Diazepam tablets, 10 mg). Salt dosage form labeling may require additional calculations for compliance with labeling requirements. Molecule and mole calculations as described above may be required for secondary label information. FDA guidance documents illustrate labeling salt drugs and associated active moieties.

Example labels below illustrate compounding labels involving salt drugs—labeling according to their active moiety or according to the bulk drug. Figure 5a illustrates a salt-ion drug label with active moiety as dosage form name; this label represents product in compliance with the drug salt policy. This labeling would likely have been approved for a salt-active moiety after USP’s salt policy was implemented in 2013. Note active moiety on primary label and both active moiety and bulk drug amount on secondary label.

Figure 5a. Salt drug dosage form label.

Figure 5b illustrates a policy-exception salt dosage form label with bulk drug name on the primary label, and bulk drug and active moiety calculation in the side panel—the opposite of Figure 5a. This label demonstrates labeling for a pre-2013 approved salt drug product—the entire salt drug weight (Olddrug palmitate) is dosed as the active moiety. This approach is applied to compounded dosage forms involving drugs identified as salt policy-exceptions to the USP salt policy. Note significant labeling differences between salt drug and salt-exception drug dosage forms.

Figure 5b. Policy-exception salt drug dosage form label.

Calculations—bulk drugs

The following describes a sequence of numeric operations for compounding calculations. Examples addressing three types of drugs (non-salts, salts, and policy-exception salts) are provided.

Non-salt dosage forms

Example drugs in this category include diazepam, digoxin, thyroid, and ospemifene (i.e., non-salt drugs). In this example, the drug amount (Drug Z) is identical to the calculated active moiety amount. No additional calculations are required beyond the active moiety amount calculation; molecule and mole calculations are not needed.

1. Medication order. Drug Z, 50 mg. 100 capsules. One capsule four times daily

The medication order is received and evaluated. Existing conditions in patients (e.g., cardiac, immunogenicity, hepatic, diabetes) affecting compounding and drug dosage must be known. The compounded dosage form amount must not exceed USP Beyond Use Date (BUD) limitations without supporting stability data.

2. Active moiety. The active moiety amount needed to provide the medication order is calculated.

Let X = active moiety amount

X = 100 capsules × Drug Z 50 mg/capsule

X = 5,000 milligrams Drug Z active moiety amount needed.

3. Drug amount. Drug Z active moiety will be provided by Drug Z bulk drug.

Active moiety amount needed: 5,000 mg. Bulk drug amount needed: 5,000 mg.

Drug Z 5,000 mg is combined with other formulation ingredients (i.e., excipients) to prepare 100 Drug Z Capsules, 50 mg.

No additional calculations are needed.

4. Labeling. Primary label and secondary label are essentially identical for non-salt drugs. No additional calculations are needed.

Primary label: Drug Z Capsules, 50 mg.

Secondary label: Each capsule contains Drug Z 50 mg.

Salt dosage forms

Dosage in salt dosage forms is defined as the drug-ion amount. Example drugs in this category include clopidogrel (bisulfate), and other salt drugs dosed according to their drug-ion active moiety. The salt drug (Drug ZA) contains the drug-ion active moiety in the molecule. Drug Z 50 mg dosage is drug-ion active moiety; the non-drug counterion is not part of the calculated active moiety dosage. The bulk drug amount providing 50 mg active moiety is calculated using mole calculations. If the drug-ion active moiety molecule mass is not available in references, it is calculated using molecule calculations described above. For this example, the Drug ZA-ion active moiety MW = 400 and Drug Z salt MW = 550.

1. Medication order. Drug Z, 50 mg. 100 capsules. One capsule four times daily

The medication order is received and evaluated as described above.

2. Active moiety. The active moiety amount needed to provide the medication order is calculated.

Let X = Drug Z-ion active moiety needed for compounding.

X = 100 capsules × Drug Z 50 mg /capsule = 5000 mg Drug Z-ion needed for compounding.

3. Drug amount. Active moiety amount needed = 5000 mg Drug Z-ion. Drug Z-ion active moiety will be provided by bulk drug ZA. The bulk Drug ZA amount as the salt form providing 5000 mg Drug Z-ion must be calculated. In other words, the drug-ion amount to be dosed is known; the bulk Drug ZA amount providing 5000 mg Drug Z-ion is not known and must be calculated. If not otherwise available, the drug-ion molecular mass is calculated as demonstrated above. The drug-ion MW should be available in the USP, drug product information, or other sources.

Let X = Drug ZA-salt bulk drug amount mg

Drug Z-ion 5000 mg / 400 MW = X milligrams Drug ZA-salt drug mg / 550 MW

5000 mg/400 MW = X mg / 550 MW

X = Drug ZA-salt drug amount = 6875 mg

Therefore, the amount of bulk Drug ZA-salt needed for compounding = 6875 mg. The 6875 mg of bulk ZA drug will provide 5000 mg Drug Z-ion active moiety. Note that the amount of Drug ZA-salt is larger (i.e., 6857 mg > 5000 mg) than the amount of Drug Z-ion. The extra bulk drug weight is counterion weight. The 6875 mg of Drug ZA-salt will be combined with other formulation ingredients to prepare 100 Drug Z 50 mg drug-ion capsules.

4. Labeling. The primary label will specify the activity moiety (Drug Z-ion) and 50 mg strength consistent with the medication order. The secondary label will specify the Drug ZA-ion amount per capsule and the equivalent Drug Z-salt amount consistent with FDA labeling guidance. Mole calculations are used to calculate Drug ZA salt amount per capsule for the secondary label.

Let X = Drug ZA mg / capsule

Drug Z-ion 50 mg active moiety / 400 MW = X mg Drug ZA drug / 550 MW

50 mg / 400 MW = X mg / 550 MW

X = Drug ZA-mg bulk drug = 69 mg that provides drug Z-ion 50 mg.

The amount of Drug ZA salt must be larger than the amount of Drug Z drug-ion stated on the label.

Primary label: Drug Z, 50 mg Capsules

Secondary label: Each capsule contains Drug Z 50 mg equivalent to Drug ZA, 69 mg.

Policy-exception salt dosage forms

Salt-exception drugs (Drug ZB) utilize the entire drug molecule for dosage (i.e., 50 mg dose is Drug ZB salt). Example drugs in this category include morphine sulfate, lithium carbonate, potassium chloride, and other drugs dosed as drug-ion with counterion. Even though the salt drug active moiety is the drug-ion part of the drug molecule, dosage and labeling are based on the entire drug molecule per USP salt policy. The 50 mg dosage represents drug-ion with counterion per USP salt policy (e.g., drug dosage is codeine phosphate, morphine sulfate, dexamethasone phosphate, or other drug-ion with counterion). Additional mole calculations are needed only for drug-name labeling per FDA guidance (Figure 5b above). Drug ZB MW and drug Z-ion MW calculations are needed for secondary labeling. Active moiety and bulk drug molecular weight assumptions: Drug Z-ion active moiety MW = 400 and Drug ZB salt MW = 550.

1. Medication order. Drug Z, 50 mg. 100 capsules. One capsule four times daily

The medication order is received and evaluated as above.

2. Active moiety amount calculations. The active moiety amount needed to provide the medication order is calculated.

Let X = Drug Z active moiety needed for compounding.

X = 100 capsules × Drug ZB 50 mg /capsule = Drug ZB 5000 mg

3. Drug amounts for compounding calculations. Drug amount needed: 5000 mg = drug dosed as salt (active moiety with counterion).

Let X = Drug ZB needed for compounding

X = 5000 mg of Drug ZB is combined with excipients to prepare 100 capsules containing Drug ZB, 50 mg.

4. Labeling calculations. The primary label will specify the bulk drug name (Drug ZB) and dosage strength. The secondary label will specify the salt molecule and the active moiety equivalent as specified in the FDA guidance (Figure 5b above). Drug Z active moiety is provided by Drug ZB policy-exception salt bulk drug. Calculate the drug-ion molecular weight as demonstrated above. The drug MW should be available in the USP, drug product information, or other sources. This calculation is needed for secondary labeling per FDA guidance.

Let X = Drug Z-ion active moiety

50 mg Drug ZB salt dosage / 550 MW = X mg Drug Z ion active moiety / 400 MW

50 mg/550 MW = X mg/400 MW

Drug Z-ion active moiety = 36 mg.

The amount of Drug Z must be smaller than the amount of Drug ZB drug stated on the label.

Primary label: Drug ZB Capsules, 50 mg

Secondary label: Each capsule contains Drug ZB, 50 mg, equivalent to Drug Z, 36 mg.

Bulk drug calculations hazards

There are numerous hazards with potential to cause errors in drug calculations and labeling. The following are most relevant to calculations topics discussed above. Additional problems such as substandard documentation, insufficient or delayed verification, and lack of personal accountability have been previously discussed (1). Prospectively addressing potential problems as part of quality risk management (i.e., what might go wrong) (12) and continuous improvement programs are essential in compounding organizations.

Objective of calculations. Personnel must clearly identify objectives in compounding calculations—exactly what is to be calculated? Identifying the calculations objective forces prospective thinking about future numeric operations. Correct equations are not possible when the values to be calculated are not clearly understood. Information required for compounding must be complete, correct, and verified if necessary. First determine what is known, and then ascertain what information is needed and unknown. After all relevant information has been compiled but before starting actual calculations, values to be calculated should be estimated; this also forces prospective thinking about calculations. Estimating a value to be calculated requires both self-discipline and time. Both Ansel (6) and Teixeira and Zatz (7) describe estimation as part of the calculations process. Each calculation should be a new effort. Do not copy from previous completed calculations; if mistakes were previously made, mistakes will be continued.

Drug selection. Some active moieties may be available in different molecular structures (e.g., phenobarbital and sodium phenobarbital) (Table I). Compounding personnel must select the appropriate drug for calculations and eventual use in compounding. While alternate drugs have the same active moiety, they may have different pharmacologic effects affecting patients or different physicochemical properties affecting the dosage form preparation. Selecting of the appropriate pharmaceutical alternative requires technical judgment. Respective alternatives may have different pharmacologic effects on patients. From the Dilantin package insert:

Table I. Active moieties and pharmaceutical alternatives.

Pharmaceutical alternates may also have different physicochemical effects on the compounded dosage form (e.g., valproic acid is a water-insoluble oil and divalproex sodium is a water-soluble salt). Personnel must evaluate drug options for use in compounding before initiating calculations. Drug alternatives used in commercial product formulations may be helpful to provide rationale for drug selection (e.g., commercial clindamycin topical preparations are formulated with clindamycin phosphate). The same bulk drug for compounding as used in approved commercial products should be the preferred alternative.

Units of measure. Units of measure must be included with all terms in equations. Writing numeric values without units of measure is the most frequent cause of calculations errors. Without the unit of measure, number identity is lost. Some calculations require a series of numeric operations; units of measure are critical when multiple terms are involved. Smartphones and calculators do not enable unit of measure notation. Numerators and denominators may be transposed when units of measure are not written. Calculations are best executed on paper with units of measure without use of calculators. Calculations should not be done in your head no matter how simple the calculations. Calculators with printouts to verify numeric entries are recommended. Auto-correct or default functions in computer systems may contribute to unit of measure errors.

Calculations evaluation. When calculations are completed, they should be critically evaluated—do the calculated values make sense? Critical thinking and common sense are key when executing calculations. Evaluation may indicate that calculated values are incorrect or unreasonable. Depending on the scale of preparation, very large or very small calculated values are probably incorrect. Incorrect calculated values may be impossible or illogical (e.g., 7000 mL IV additive, 0.0005 mL drug solution, or 30 × 30 mL vials to be added to an IV). Comparison of the calculated value to the initial estimated value should be done; if the calculated value is significantly different from the estimate, then something is wrong.

Summary

This discussion demonstrated numeric calculations for compounded dosage forms using bulk drugs as sources of active moieties. Calculations are described for non-salt, salt, or policy-exception salt drugs. Despite an identical medication order for all examples, the actual drug dosage and drug amount is different for each drug type. The key to understanding these calculations lies with understanding respective active moiety dosages. Non-salt drugs are dosed with the entire molecule; salt drugs are dosed per the drug-ion; policy-exception salts are dosed with the entire salt molecule (drug-ion with counterion). Subsequent calculations reflect respective dosages. Salts will thus require larger bulk drug amounts to compensate for the bulk drug counterion. Policy-exception salts provide smaller drug active moiety amounts for the same labeled drug dosage.

A standardized calculations process is utilized throughout. The calculations process begins with the medication order; the amount of active moiety needed for dosage form preparation is then determined. The applicable type of bulk drug is identified. General equations (active moiety amount, molecule, and mole calculations) are described. After calculations, drug naming on dosage form labels must be consistent with the drug type and active moiety amounts.

Differences between calculations and labeling for non-salt, salt, and salt exception drugs are presented in Table II. Calculations for compounded dosage forms with non-salt drugs are straightforward. Non-salt active moieties and drugs are the same molecule; the entire drug molecule is the active moiety. Non-salt drugs are named using their drug name. Primary and secondary labels for non-salt dosage forms are identical.

Table II. Non-salt, salt, and policy-exception salt bulk drug calculations comparison. (Medication order: Drug Z, 50 mg, 100 capsules.)

Calculations for salt and salt-exception drugs are much different. Salt drugs identify the drug-ion as the active moiety and amount dosed in the dosage form. Policy-exception salt drugs are dosed using the entire salt molecule including the counterion. Policy-exception salt drugs thus provide less actual drug-ion active moiety than the labeled amount of drug. Regarding labeling, the compounded salt dosage form is named/labeled as the drug ion; the policy-exception salt dosage form is named/labeled as the drug name with counterion. This approach to salt drugs was adopted by USP and FDA in 2013. Specific policy-exception salt drugs are identified in regulatory references (2–5).

Key points for calculations of respective drug types and comparative values are presented in Table II. Medication orders, dosages, and molecular weights are identical in all calculations.

• Line 3. Drug amount per capsule. The amount of bulk drug per capsule needed for compounding is largest for a salt drug (69 mg vs. 50 mg for other molecules). The additional required mass compensates for the inactive counterion content in the salt molecule.
• Line 5. Drug needed for compounding. In turn, the bulk drug amount to prepare 100 capsules is likewise largest for the salt dosage form (6875 mg vs. 5000 mg).
• Line 6. Actual active moiety dose. The actual active moiety dose is smallest for the salt-exception dosage form (36 mg vs. 50 mg. for other dosage forms).
• Line 7. Primary label. The policy-exception salt dosage form label includes the counterion in the drug salt name (Drug ZB) reflecting the policy-exception salt dosage.
• Line 8. Secondary label. The actual active moiety amounts in the salt drugs reflect their respective amounts in salt and policy-exception salt dosage forms. The active moiety in the salt dosage form is 50 mg; the active moiety in the policy-exception salt dosage form is 36 mg.

Potential calculations and associated problems are identified. These included not clearly identifying the objective of calculations, drug selection problems, omitting units of measure when writing equations, and not critically evaluating calculated values.

References

1. Pluta, P. L.; Mancini, A. M.; Thakar, N. B.; and Chaiyaperm, V. Pharmaceutical Compounding Calculations in a Workplace Environment. Pharmaceutical Technology Trends in Manufacturing eBook May 2024.
2. USP, Guidance for Implementation and Exceptions: The Monograph Naming Policy for Salt Drugs Substances in Drug Products and Compounded Preparations in General Chapter <1121> Nomenclature (September 2019).
3. USP, USP General Chapter <1121>, “Nomenclature,” USP35–NF30 (Rockville, MD, 2011).
4. FDA, Guidance for Industry, Naming of Drug Products Containing Salt Drug Substances (CDER, June 2015).
5. FDA, USP Salt Policy (December 2014). YouTube.com, Dec. 1, 2014 (accessed April 29, 2025).
6. Ansel, H. C. Pharmaceutical Calculations, 14th edition; Wolters Kluwer/Lippincott, Williams, & Wilkins, Philadelphia, PA, 2013.
7. Teixeira, M. G. and Zatz, J. L. Pharmaceutical Calculations, 5th edition; John Wiley & Sons, Hoboken, NJ, 2017.
8. Allen, L. V., Jr. Pharmaceutical Compounding Calculations. In The Art, Science, and Technology of Pharmaceutical Compounding, 6th edition; American Pharmacists Association, Washington, D.C., 2020.
9. Drugs.com. Phenytoin Dosage. Drugs.com, last updated March 21, 2025 (accessed April 29, 2025).
10. Gupta, D; Bhatia, D.; Dave, V.; Sutariya, V.; and Gupta, S. V. Salts of Therapeutic Agents: Chemical, Physicochemical, and Biological Considerations. Molecules 2018, 23 (7) 1719. DOI: 10.3390/molecules23071719
11. Drug Enforcement Administration. General Information Regarding the Combat Methamphetamine Epidemic Act of 2005 (Title VII of Public Law 109-177). USDOJ.gov, May 2006 (accessed April 29, 2025).
12. FDA. Guidance for Industry, Q9(R1) Quality Risk Management (CDER/CBER, May 2023).

Acknowledgments

Comments from Alan M. Mancini, RPh, pharmaceutical educator; Richard Poska, RPh, managing director, Flexo CMC Consulting; Jan M. Keresztes, RPh, PharmD, pharmaceutical educator; and William R. Porter, PhD, principal scientist, Peak Process Performance Partners, are greatly appreciated.

About the authors

Paul L. Pluta, RPh, PhD, is a pharmaceutical scientist with pharma industry, academic teaching, journal editorship, community pharmacy, and hospital pharmacy experience.

Nishant B. Thakar, RPh, PharmD, is associate professor of Clinical Sciences, Roosevelt University College of Science, Health, and Pharmacy, Schaumburg, IL, USA.

Varanya Chaiyaperm, RPh, PharmD is clinical assistant professor, University of Illinois at Chicago Retzky College of Pharmacy, Chicago, IL, USA.