An Over-the-Counter Drug (OTC) is a medication that can be purchased without a prescription from a healthcare provider. These drugs are typically used to treat common ailments such as headaches, colds, and allergies. They are considered safe and effective for public use when taken as directed. OTC drugs are regulated by the Food and Drug Administration (FDA) in the United States. They must meet specific safety and efficacy standards before being sold to consumers. Common examples include ibuprofen, acetaminophen, and antihistamines. Always read the label for dosage instructions and potential side effects.