Oral And Drug Delivery System

*Rectal administration – Medicines administered into the body by this route are absorbed very quickly. Suppositories are available for this route of administration and are inserted high into the rectum.

Absorption – “How the drugs enter the circulation process through the body, and how they resist general breakdown by the stomach, liver, and the intestines”. Some of the factors that affect the absorption of drugs in the body is as follows, “acidity of the stomach, Physiochemical properties, Presence of food in the stomach or intestine, and Routes of administration”,

Based on ¨Principles of Pharmacokinetics¨, ¨pharmacokinetics is the study of absorption, distribution, metabolism, and excretion¨ (Ratain 2003). In other words, the drug's pharmacokinetics determines the duration and the intensity of the effect on the body. Absorption rate can be affected by the drug itself, such as: rate of dissolution, lipid solubility, and route (VandeWaa 2016). The absorption process starts by the route of admission, in this case oral. The oral, or by mouth, route of administration for drugs is the most common. When a pill is taken by mouth, it travels down to the stomach, were most pills dissolve. While in the stomach, some kinds of pills are absorbed into the stomach lining, but some move on to the small intestine. Every pill eventually ends up in the bloodstream and circulate through the body to tissues and organs (Howell 2017). Once passive diffusion occurs, the cells absorb the molecules of the medicine. Then, the molecules of the medicine will exit the cells and travel in the bloodstream for the distribution process.

The ability to become reflective in practice has become a necessary skill for health professionals. This is to ensure that health professionals are continuing with their daily learning and improving their practice. Reflective practice plays a big part in healthcare today and is becoming increasingly noticed.

Pharmacokinetics (PK): Well absorbed in the gastrointestinal tract, metabolised in the liver and excreted in the urine. 1-2,4 The average PK parameters of DVS with once-daily dosing are1,4:

The nasal route has been extensively used for topical treatments in the past, for example, in the treatment of rhinitis with antihistamines. However, due to the appealing drug absorption potential of the nasal mucosa, intranasal administration for the systemic delivery of drugs has grown in popularity, allowing it to be considered as an alternative parenteral route of administration 11. The nasal mucosa consists of pseudostratified columnar epithelium that lies on top of a highly vascularised basement membrane. The columnar cell surface possesses microvilli which extensively aid systemic absorption through a greatly increased surface area 5. The highly vascularised mucosa plays a significant role in systemic absorption as blood flow, and subsequently the concentration gradient across the membrane, has a major influence in the absorption of drugs into the systemic circulation 1. These anatomical aspects, coupled with the nasal cavity’s thin and porous endothelial membrane provide an attractive option for a range of therapeutic applications 5. An example of such an application is the administration of fentanyl. Nasal delivery of fentanyl exhibits a rapid onset of action due to the advantageous nasal anatomy and provides a Tmax of approximately 7 minutes, a

Enteral Route- The purpose is direct absorption into the bloodstream and directly into the GI Tract. Some advantages are that it is Safe, Administered, and convenient. Some disadvantages are slow onset, No oral nasogastric, or gastrostomy tube.

After oral administration, APAP is rapidly absorbed by the GI tract; its volume of distribution is

The PPIs are inactive pro drugs that are carried in the bloodstream to the parietal cells in the gastric mucosa. The pro drugs readily cross the parietal cell membrane in the cytosol. These drugs are weak bases and therefore have a high affinity for acidic environments. They diffuse across the secretory membrane on the parietal cell into the extracellular secretory canaliculus, the site of active proton pump. Under this acidic conditions the prodrugs are converted to their active form, which irreversibily binds the proton pump, inhibiting acid secretions. Since the’ active principles ‘ forms at a low pH it concentrates selectively in the acidic enviorment of the proton pump and results in extremely effective inhibition of acid secretion.The different PPIs(Omeprazole,Esomeprazole,Lanzoprazole, Pantoprazole and Rabeprazole ) bind to different sites on the proton pump, which may explain their differences in potency on a milligram per milligram basis.

Pharmacokinetics consists of three components, absorption, distribution, and clearance. Absorption, especially from the oral route is the least influenced by the aging process and slows down, but remains complete (Adams et al., 2011). As the number of drugs ingested increases, the risk that absorption is interrupted increases (Adams et al., 2011). Distribution is significantly impacted with age. Older people have more body fat and less water than younger people. As a result, a drug that is fat soluble will remain in older bodies

Pharmacology is the study of the effects drugs have and how they exert them. Drugs can be administered enteral or parenteral. [1] Enteral refers to any form of administration that involves the alimentary tract. The four enteral routes of administration include the mouth, sublingual, buccal and rectal. Parenteral refers to routes of administration outside of or beside of the alimentary tract. The parenteral route includes intravascular (IV), Intramuscular (IM) and subcutaneous (SC) routes of administration. The parenteral routes are used for drugs that are poorly absorbed or that are unstable in the GI tract. The parenteral routes are used in unconscious patients or when a fast response is needed as it provides the

Oral forms of cephalosporins are well absorbed from the gastrointestinal (GI) tract. Absorption is delayed by food, except for in oral ester prodrugs where absorption is

Following the ingestion of the barium sulfate a high KUB radiograph was taken using 100 kV and 80 mAs with 50 inch SID. The central ray was 3 inches above the level of her iliac crest and the exposure was taken at the end of expiration. The time was annotated on each and every radiograph taken throughout the study. The patient was then rolled onto their right side to allow the stomach to drain. The patient remained lying on her right side for 15 minutes and then turned back to the supine position for another high KUB radiograph of the stomach. The same technical factors were used of 100 kV and 80 mAs and a SID of 50 inches with the central ray 3 inches above her iliac crest. On the 15 minute radiograph the barium had moved to the second part of the small intestine the jejunum. The patient requested that she stay lying in the supine position instead of lying on her right side because it was more comfortable for her. The technologist said that was fine because the barium did move. However, if the barium had not moved, she would have been returned into the right lateral position. If the patient is able to get up and walk around at this time it is ideal to allow the barium to start moving through the small

In the past years, drug delivery via the nasal route has established itself as a competitor and an alternative route over other routes of administration. It provides a higher degree of patient compliance and drugs can be painlessly self-administered by the patient (Illum, 2003). Drugs administered through nasal route are absorbed rapidly and can reach therapeutically effective plasma levels quickly due to highly permeable membranes and rich vasculature of the nasal cavity (Majithiya et al., 2006). In addition, the nasal route offers further advantages over the oral route, especially for those drugs that have poor oral bioavailability due to high hepatic first-pass metabolism, pH instability and enzyme degradation in GIT (Ugwoke et al., 2001).

Limited permeability across the cornea, drainage of the administered dose into the lachrymal duct, leads to systemic side effects and short term therapeutic effect due to eye blinking results in frequent dosage regimen.