What factors determine the route of administration for a drug?

The reason for choice of routes of drug administration are governing by various factors:

• Physical and chemical properties of the drug.
• Site of desired action: the action may be localised and approachable or generalised and not approachable.
• Rate of extent of absorption of the drug from different routes.

Why some drug doses are different when given IV rather than orally?

Some drugs that are particularly well absorbed by the gastrointestinal mucosa may have bioavailability comparable to that of an IV dose – for example the antibiotic ciprofloxacin. Most drugs do not have this availability by the oral route so the dose given orally is usually higher than that given parenterally.

Why are oral doses higher than IV?

If bioavailability is low then the oral dose needed has to be increased so that a given dose achieves the appropriate serum concentration. Since the absorption of an oral drug is slower than an IV drug and the drug takes longer to enter the circulation, clearing the drug will also most likely take a longer time.

How will the intravenous administration be converted to oral administration?

Intravenous-to-oral (IV-to-PO [per oral]) switch therapy is a treatment procedure to convert the administration of medication from intravenous to oral. The procedure involves starting hospitalized patients on an initial intravenous therapy and stepping it down to oral therapy as early as possible.

What are the selection criteria for route of administration?

Routes of administration of a drug are determined by its physical and chemical properties, patient characteristics and the rapidity of response desired. Major routes are oral, parenteral and topical.

Why is the oral route of administration safer?

Oral route Many drugs can be administered orally as liquids, capsules, tablets, or chewable tablets. Because the oral route is the most convenient and usually the safest and least expensive, it is the one most often used. However, it has limitations because of the way a drug typically moves through the digestive tract.

What factors determine oral bioavailability?

Drug bioavailability after oral administration is affected by anumber of different factors, including physicochemical properties of the drug, physiological aspects, the type of dosage form, food intake, biorhythms, and intra- and interindividual variability of the human population.

What happens to a drug when administered orally?

Oral route For drugs administered orally, absorption may begin in the mouth and stomach. However, most drugs are usually absorbed from the small intestine. The drug passes through the intestinal wall and travels to the liver before being transported via the bloodstream to its target site.

Can IV medications be given orally?

If an IV/IM preparation is deemed to be safe and efficacious when administered orally, it is imperative to draw up the required amount in an oral syringe that has an auxiliary label stating “For Oral Use Only.” In the hospital setting, several cases of serious (and sometimes fatal) medical errors have occurred in …

What factors determine which patients continue on intravenous antibiotic or are changed to oral antibiotic therapy?

The 5 items were the: 1) need to be afebrile for 24 hours prior to conversion to oral antibiotics; 2) need for a standard duration of intravenous antibiotics to treat pneumonia; 3) appropriate temperature threshold for conversion to oral antibiotic therapy; 4) importance of a normalized white blood cell count for …

Why are drugs typically administered by injection and not orally in emergency situations?

It may be used instead of oral delivery because some drugs are destroyed by the digestive system when a drug is swallowed. Intramuscular injections are absorbed faster than subcutaneous injections. This is because muscle tissue has a greater blood supply than the tissue just under the skin.

Can we use oral route for drug administration in unconscious patient?

The oral route of drug administration is not preferred in: Unconscious patients. Patients with restrictions to oral intake. Patients who are vomiting.