Table 1.

Traditional drug delivery methods

Drug delivery methods	Advantages	Disadvantages	References
Oral administration	Contains both solid and liquid dosage forms Noninvasive administration Simple and convenient	The absorption of the drug is strongly influenced by the first-pass effect in the liver and the destruction of digestive enzymes in the gastrointestinal tract Drugs cannot be orally administered to unconscious persons	[23, 24]
Sublingual administration	Includes sublingual and buccal routes, avoids the first-pass effect, easy to administer	Irritating to the oral mucosa Taste not preferred by patients	[25, 26]
Injection administration	Includes intravenous, intramuscular and subcutaneous routes Avoids the first-pass effect Precise control of blood concentration Can be given to unconscious patients	There is a risk of phlebitis, drug extravasation, and allergies The effect is related to changes in blood flow Taking stimulating drugs can cause pain	[27– 29]
Rectal administration	Can be used for patients who cannot swallow, vomit, or are unconscious Avoids the first-pass effect	Not convenient to use Drug absorption is slow or erratic Not accepted by the patient	[29–31, 65, 72, 75]