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Overview of Generic Drugs and Drug Naming


Daphne E. Smith Marsh

, PharmD, BC-ADM, CDCES, University of Illinois at Chicago College of Pharmacy

Reviewed/Revised Apr 2023
Topic Resources

Medications are drugs used therapeutically (that is, to treat medical conditions). Drugs often have several names. When a drug is first discovered, it is given a chemical name, which describes the atomic or molecular structure of the drug. The chemical name is usually too complex and cumbersome for general use. Next, a shorthand version of the chemical name or a code name (such as RU 486) is developed for easy reference among researchers.

When a drug is approved by the Food and Drug Administration (FDA—the U.S. government agency responsible for ensuring that drugs marketed in the United States are safe and effective), it is given a

  • Generic (official) name

  • Brand (proprietary, trademark, or trade) name

For example, phenytoin is the generic name and Dilantin is a brand name for the same drug, which is a commonly used antiseizure drug.

The generic name is assigned, in the United States, by an official body—the United States Adopted Names (USAN) Council.

The brand name is developed by the company requesting approval for the drug and identifies it as the exclusive property of that company.

When a drug is under patent protection, the company markets it under its brand name. When the drug is off patent (no longer protected by patent), the company may market its product under either the generic name or brand name. Other companies that file for approval to market the off-patent drug must use the same generic name but can create their own brand name. As a result, the same generic drug may be sold under either the generic name (for example, ibuprofen) or one of many brand names (such as Advil or Motrin).

Generic and brand names must be unique to prevent one drug from being mistaken for another when drugs are prescribed and prescriptions are dispensed. To prevent this possible confusion, the FDA must agree to every proposed brand name.

Government officials, doctors, researchers, and others who write about the new compound use the drug’s generic name because it refers to the drug itself, not to a particular company’s brand of the drug or a specific product. However, doctors often use the brand name on prescriptions, because it is easier to remember and doctors usually learn about new drugs by the brand name.

Generic names are usually more complicated and harder to remember than brand names. Many generic names are a shorthand version of the drug’s chemical name, structure, or formula. In contrast, brand names are usually catchy, often related to the drug’s intended use, and relatively easy to remember, so that doctors will prescribe the drug and consumers will look for it by name. Brand names often suggest a characteristic of the drug. For example, Lopressor lowers blood pressure, Glucotrol controls high blood sugar (glucose) levels, and Skelaxin relaxes skeletal muscles. Sometimes, the brand name is simply a shortened version of the drug’s generic name—for example, Minocin for minocycline.

The term generic, when applied to such items as foods and household products, is used to describe a less expensive, sometimes less effective or lower-quality copycat version of a brand-name product. However, generic drugs, although less expensive than the comparable brand-name drug, are generally as effective and of the same quality as the brand-name drug (see Bioequivalence and Interchangeability of Generic Drugs Bioequivalence and Interchangeability of Generic Drugs Medications are drugs used therapeutically (that is, to treat medical conditions). When one company develops a generic version of another company's brand-name drug, the new company’s experts... read more ). In fact, generic drug makers manufacture many brand-name products for companies that control the brand names. Sometimes, more than one generic version of a drug is available. For example, many manufacturers sell versions of acetaminophen, a nonprescription drug commonly used to relieve pain and fever.


Patent Protection for Drugs

In the United States, a company that develops a new drug can be granted a patent for the drug itself, for the way the drug is made, for the way the drug is to be used, and even for the method of delivering and releasing the drug into the bloodstream. Thus, a company often owns more than one patent for a drug. Patents grant the company exclusive rights to a drug for 20 years. Additional patents can sometimes be filed to extend the patent life. Usually, about 10 years elapse between the time a drug is discovered (when the patent is obtained) and the time the drug is approved for human use, leaving the company only about half of the patent time to exclusively market a new drug. The Food and Drug Administration (FDA) may choose to accelerate the approval process for drugs to treat acquired immunodeficiency syndrome (AIDS), cancer, and other life-threatening disorders when no current effective treatment exists.

After a patent has expired, other companies may produce and sell a generic version of the drug that is approved by the FDA. They typically sell their product at a lower price than the original brand-name drug because the generic manufacturer does not have to recover the original costs of drug development and usually spends much less on marketing. A generic drug may be sold under its generic name or under a brand name (a branded generic drug) but not under the brand name used by the original patent holder.

Not all off-patent drugs have generic versions. Sometimes a drug is too hard to duplicate, or adequate tests are not available to prove that the generic drug acts the same as the brand-name drug. Sometimes the market for the drug is so small that producing another version does not make good business sense.

Nonprescription Generic Drugs

Generic versions of some nonprescription (over-the-counter) drugs Overview of Over-the-Counter Drugs Over-the-counter (OTC) drugs are those available without a prescription. OTC drugs enable people to relieve many annoying symptoms and to cure some diseases simply and without the cost of seeing... read more are often sold as house brands by drug chains or cooperatives, usually at a lower cost. These drugs are evaluated in the same way that generic prescription drugs are evaluated and must meet the same requirements.

Pharmacists can advise which generic over-the-counter drug products should be as effective as the original. However, a consumer may prefer one product to another because of appearance, taste, consistency, or other characteristics.

More Information

The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

  • U.S. Food and Drug Administration: This governmental agency ensures the safety and efficacy of all human and veterinary medications, biological o, and medical devices. It also ensures the safety of the nation's food supply, cosmetics, and radiological products.

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