Topical is not a route of drug administration, but rather a method of applying a drug to the skin or mucous membranes.

Pharmacology is the study of the effects of drugs on living organisms, including their absorption, distribution, metabolism, and excretion.

Enzyme-linked receptors are not a type of drug receptor, but rather a type of enzyme that is activated by a drug.

Bioactivation is the process by which a drug is converted into a more active form, typically by enzymes in the liver.

Metabolism is not a type of drug interaction, but rather a process by which drugs are converted into more or less active forms.

Pharmacodynamics is the study of the relationship between drug concentration and its effects.

Teratogenic reactions are not a type of adverse drug reaction, but rather a type of birth defect caused by exposure to a drug during pregnancy.

Clinical trials are studies conducted in humans to evaluate the safety and efficacy of drugs.

Phase IV is not a type of clinical trial, but rather a phase of drug development that occurs after a drug has been approved for marketing.

Drug development is the process of developing a new drug, from the initial discovery of a lead compound to the final approval of the drug for marketing.

Injection is not a type of drug dosage form, but rather a route of drug administration.

Pharmacokinetics is the study of the fate of drugs in the body, including their absorption, distribution, metabolism, and excretion.

Acetyltransferases are not a type of drug metabolism enzyme, but rather a type of enzyme that catalyzes the transfer of an acetyl group from one molecule to another.

Ecotoxicology is the study of the effects of drugs on the environment, including their effects on plants, animals, and ecosystems.

The Centers for Disease Control and Prevention (CDC) is not a drug regulatory agency, but rather a public health agency that works to prevent and control disease.