Drug Information Q&A Q9. Why are there different types of medicines, such as oral and injectable medicines?

Answer

Different diseases and symptoms have different needs for different types of medicines. Therefore, in order to expand treatment options, various types of medicines have been developed to meet various needs.

Explanation

(1) Medicines to be taken by mouth

Orodrugs are available in tablet, capsule, powder, and syrup formulations.

Tablets, capsules, and granules are commonly used because they are easy to swallow, portable, and easily stored.

(2) Injections

Injectable drugs are fast-acting. For example, intravenous injections reach the affected area within 1 to 3 minutes after entering the bloodstream, making them much faster-acting than oral medications (15 to 30 minutes).

(3) Suppositories

Suppositories are drugs that are inserted through the anus. Since the ingredients are absorbed through the rectum, they are less susceptible to stomach acid, unlike oral medications, and are effective more quickly.

(4) Adhesives and ointments

Paste and ointment drugs are absorbed through the skin. They are often found in poultices and ointments used to treat bruises, sprains, and skin diseases.

(5) Inhalants

Inhalants are drugs that are inhaled through the mouth and act on the lungs and bronchial tubes, and are used to treat respiratory illnesses such as asthma and pathogens that multiply in the respiratory system, such as influenza. They are characterized by their quicker onset of action at smaller doses than oral medications.

(6) Eye drops

Eye drops are administered directly into the eye. To minimize irritation to the eye, most eye drops are adjusted to have a pH (acidity/alkalinity) and osmolarity similar to that of tears.

In this way, various forms of drugs have been developed to be effective once they are in the body.

In addition, in some cases, new forms have been developed to meet the required needs. A typical example is nitroglycerin used for angina attacks (see Q10).

There are also enteric solvents, which are drugs that are easily decomposed by stomach acid, that are coated on the surface so that they are not decomposed in the stomach and reach the intestines, where they are dissolved and absorbed for the first time.

Drugs that need to be administered quickly or that are degraded in the gastrointestinal tract can be injected subcutaneously or intramuscularly or intravascularly.

In this way, each form and type of drug has its own purpose and meaning.

Chart/Column

9｜Types of drugs

The physician assesses the patient's symptoms and prescribes the drug appropriately according to the symptoms, the area of use, and the patient's physical condition.

MINI Column Nitroglycerin and Nobel

It was known from early on that nitroglycerin has the property of exploding when heated or when subjected to vibration or pressure, in addition to its vasodilating action.

Alfred Nobel, the founder of the Nobel Prize, invented dynamite, which was made by soaking diatomaceous earth in nitroglycerin, after conducting extensive research on the use of this property to create explosives. Although he amassed an enormous fortune from the production of dynamite, he suffered from rheumatic heart disease in his later years. The drug he used to cure his heart disease was nitroglycerin. Perhaps no one was more indebted to nitroglycerin than Nobel.

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