Pharmaceutical Regulations: Durham-Humphrey Amendment

Durham-Humphrey Amendment

• Establishes distinct labeling requirements for prescription drugs and over-the-counter (OTC) drugs within Section 502 of the FDCA.
• Prior to the amendment, manufacturers could label the same drug as OTC or prescription, leading to inconsistencies.

Classification of Prescription Drugs

• A drug is categorized as prescription if:
  • It is unsafe without practitioner supervision due to potential harm or necessary collateral measures.
  • The new drug application explicitly indicates it is prescription only.

FDA's Role in Drug Status Change

• The FDA must prove the following to reclassify a drug from OTC to prescription:
  • The drug demonstrates harmful pharmacological or toxic effects without physician oversight.
  • Evidence that unsupervised use has caused harm.
  • Collateral measures are needed to ensure safe drug usage.

Collateral Measures

• If a drug cannot cure a condition, a delay in seeing a doctor could result in further harm.

Prescription Forms

• Allows for written or oral prescriptions, with electronic prescriptions recognized after 2000.

Labeling Requirements for Pharmacists

• Prescription refills must be specified in the original prescription.

Pharmacists' Labeling Obligations

• Pharmacists must include on labels:
  • Name and address of the dispenser.
  • Serial number and date of prescription filling.
  • Name of the prescriber and patient.
  • Directions for use and cautionary statements.

Drug Expiration Guidelines

• Most dispensed drugs expire no later than the manufacturer’s expiration date or one year post-dispensing, whichever comes first.
• Insulin products have an expiration of 24 months from the date of manufacture.

OTC Products and Expiration

• OTC products exempt from expiration dating are stable for at least three years, without dosing limitations, suitable for regular use, e.g., toothpaste.

Kefauver-Harris Amendment

• Required all marketed drugs, both OTC and prescription, to undergo efficacy evaluations.

Evaluating OTC Products

• The FDA assesses OTC products based on therapeutic categories instead of individual review.

Manufacturer Actions for Non-compliance

• Products lacking approved ingredients must either be reformulated, relabeled, or withdrawn.

OTC Drug Categories

• Category I: Recognized as safe and effective.
• Category II: Not recognized as safe or effective.
• Category III: Insufficient data for classification.

Prescription to OTC Transition

• Mechanisms include:
  • Manufacturer's request via supplemental application.
  • Petitioning the FDA.
  • Transition during the OTC review process.

Brand vs. Generic Drug Decisions

• The same drug may have different statuses (OTC or prescription) depending on the manufacturer; pharmacists must adhere to the label.

Behind-the-Counter Drugs

• Certain drugs, such as insulin and pseudoephedrine, are classified as behind-the-counter, available only in pharmacies with required counseling.

Prescription Refills Authorization

• Only the prescriber can authorize prescription refills, and pharmacists must verify authorization.

Prescriptive Authority

• Varies by state law, granting different health care practitioners the ability to prescribe.

Collaborative Practice Agreement

• Legislation in many states permits pharmacists to initiate or adjust therapies collaboratively with physicians.

Authority to Dispense Prescription Drugs

• Physicians follow the same standards (DHA) as pharmacists when dispensing drugs.

Patient Package Inserts

• Required for specific drugs, including oral contraceptives and IUDs, to ensure patients receive vital information.

Timing for Patient Package Inserts

• Must be provided before the first dose and within 30 days after.

Medication Guides

• Labeling for drugs posing significant risks, ensuring patients understand potential adverse effects and proper adherence.

Examples of Drugs Requiring Medication Guides

• Includes medications like Accutane, Lotronex, and Ambien.

Unlabeled Indications in Medicine

• Common due to practitioners’ quick adaptation to new uses and manufacturers’ limited NDA approvals.

Pharmacists' Duty Regarding Unlabeled Indications

• Must contact prescribers if risk appears unreasonable concerning unlabeled drug uses.

Brand vs. Generic Decision Authority

• The prescriber ultimately decides whether to use a brand or generic drug in Massachusetts.

Definitions and Equivalence

• Bioequivalence: Similar bioavailability under identical conditions.
• Pharmaceutical equivalence: Same active ingredients, identical strength and form.
• Therapeutic equivalence: Expected to have the same clinical effects and safety profile.

Exceptions from Orange Book

• Drugs marketed before 1938 and certain generics may be therapeutically equivalent but not listed.

Narrow Therapeutic Index Drugs

• Examples include carbamazepine, lithium, and warfarin, requiring careful monitoring.

FDA Bioequivalence Standards

• Allow a 80-125% range in bioavailability.

Steps for Drug Interchangeability in MA

• Identify drug product and verify its equivalence in the Orange Book based on dosage and strength.

Tax-Free Alcohol Uses

• Utilized for medicinal and research purposes.

Alcohol Used in Retail Pharmacies

• Typically involves tax-paid ethyl alcohol from authorized outlets.

Storage and Handling of Tax-Free Alcohol

• Must be securely locked and properly labeled, with requirements for obliterating labels before discarding containers.

Definition of Hazards under PPPA

• Substances that are customarily used in households and defined under several federal acts.

Child-Resistant Container Standards

• Containers must be designed to be opened by 80% of adults and not by 90% of children under five.

Reuse of Bottles

• Glass containers can be reused; plastic containers can be reused if caps are replaced.

Exemptions from Child-Resistant Container Rule

• Include requests by prescribers, certain OTC products, dispensed items to institutionalized patients, and immediate use prescription drugs.

Prescription Drugs Exempt from Child-Resistant Containers

• Includes SL nitroglycerin and sodium fluoride among others.