Oral administration is a

route of administration A route of administration in pharmacology and toxicology is the way by which a medication, drug, fluid, poison, or other substance is taken into the body. Routes of administration are generally classified by the location at which the substance i ...

where a substance is taken through the mouth. Per os abbreviated to P.O. is sometimes used as a direction for

medication A medication (also called medicament, medicine, pharmaceutical drug, medicinal drug or simply drug) is a drug used to diagnose, cure, treat, or prevent disease. Drug therapy (pharmacotherapy) is an important part of the medical field and re ...

to be taken orally. Many medications are taken orally because they are intended to have a systemic effect, reaching different parts of the body via the

bloodstream The blood circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the entire body of a human or other vertebrate. It includes the cardiovascular system, or vascular system, tha ...

, for example. Oral administration can be easier and less painful than other routes, such as injection. However, the onset of action is relatively low, and the effectiveness is reduced if it is not absorbed properly in the digestive system, or if it is broken down by digestive enzymes before it can reach the bloodstream. Some medications may cause gastrointestinal side effects, such as nausea or vomiting, when taken orally. Oral administration can also only be applied to conscious patients, and patients willing and able to swallow.

Terminology

''Per os'' (; ''P.O.'') is an adverbial phrase meaning literally from Latin "through the mouth" or "by mouth". The expression is used in medicine to describe a treatment that is taken orally (but not used ''in'' the mouth such as, for example,

caries Tooth decay, also known as cavities or caries, is the breakdown of teeth due to acids produced by bacteria. The cavities may be a number of different colors from yellow to black. Symptoms may include pain and difficulty with eating. Complicatio ...

prophylaxis). The abbreviation ''P.O.'' is often used on

medical prescription A prescription, often abbreviated or Rx, is a formal communication from a physician or other registered health-care professional to a pharmacist, authorizing them to dispense a specific prescription drug for a specific patient. Historica ...

Scope

Oral administration includes: * Buccal, dissolved inside the cheek * Sublabial, dissolved under the lip *

Sublingual administration Sublingual (abbreviated SL), from the Latin for "under the tongue", refers to the pharmacological route of administration by which substances diffuse into the blood through tissues under the tongue. The sublingual glands receive their primar ...

(SL), dissolved under the tongue, but due to rapid absorption many consider SL a parenteral route Enteral medications come in various forms, including oral solid dosage (OSD) forms: * Tablets to swallow, chew or dissolve in water or under the tongue * Capsules and chewable capsules (with a coating that dissolves in the stomach or bowel to release the medication there) * Time-release or sustained-release tablets and capsules (which release the medication gradually) * Powders or granules and oral liquid dosage forms: * Teas * Drops * Liquid medications or syrups

Facilitating methods

Concomitant ingestion of

water Water (chemical formula ) is an inorganic, transparent, tasteless, odorless, and nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living organisms (in which it acts as a ...

facilitates in swallowing tablets and capsules.TheFreeDictionary > oral administration of medication
Citing: Mosby's Medical Dictionary, 8th edition. 2009 If the substance has disagreeable

taste The gustatory system or sense of taste is the sensory system that is partially responsible for the perception of taste (flavor). Taste is the perception produced or stimulated when a substance in the mouth reacts chemically with taste receptor ...

, addition of a

flavor Flavor or flavour is either the sensory perception of taste or smell, or a flavoring in food that produces such perception. Flavor or flavour may also refer to: Science *Flavors (programming language), an early object-oriented extension to Lis ...

may facilitate

ingestion Ingestion is the consumption of a substance by an organism. In animals, it normally is accomplished by taking in a substance through the mouth into the gastrointestinal tract, such as through eating or drinking. In single-celled organisms ingest ...

. Substances that are harmful to the

teeth A tooth ( : teeth) is a hard, calcified structure found in the jaws (or mouths) of many vertebrates and used to break down food. Some animals, particularly carnivores and omnivores, also use teeth to help with capturing or wounding prey, tear ...

are preferably given through a

straw Straw is an agricultural byproduct consisting of the dry stalks of cereal plants after the grain and chaff have been removed. It makes up about half of the yield of cereal crops such as barley, oats, rice, rye and wheat. It has a number ...

References

{{Dosage forms Medical terminology Routes of administration

Terminology

Scope

Facilitating methods

See also

References