Medication orally administered

Intravenous (i.v.) solutions are commonly administered to patients in hospitals, long-term care facilities, and ambulances. They are used primarily to replace body fluids and to serve as a vehicle for injecting drugs into the body. The advantages of this pharmaceutical dosage form include the rapid onset of action, the ability to treat patients unable to take medication orally and the ability to administer a medication unavailable in any other dosage form. 

Modern Delivery Strategies Physiological Considerations for Orally Administered Medications... 

Medical scientists mainly rely on the measurement of bioavailability of a drug as a positive indicator of therapeutic equivalence, because clinical efficacy for orally administered drugs depends on the degree of absorption and the presence of the active ingredient in the blood stream. 

Flavoring, sweetening, and coloring are important to enhance patient compliance when medications are orally administered. These can often be adjusted to meet the preferences of the patient. 

IV formulation - Administer 30 mg/day by IV infusion over 30 minutes for up to 7 days. Once the patient is able to take medications orally, therapy can be switched to an oral lansoprazole formulation for a total of 6 to 8 weeks. 

Oral bioavailability is one of principal pharmacokinetic properties in drug discovery. It represents the percentage of an oral dose that is available to produce pharmacological actions, in other words, the fraction of the oral dose that reaches the system circulation in an active form. By the definition, when a drug is administered intravenously, its bioavailability is 100%. However, when a medication is administered via other routes, especially orally, its bioavailability decreases due to incomplete absorption and first-pass metabolism. 

The primary indication for standard i.m. administration is when a patient is too disturbed to take oral medication. Because drugs are more rapidly absorbed when given parenterally and their effect occurs about 60 minutes faster than with oral administration (i.e., 30 vs. 90 minutes), violent or otherwise dangerously disturbed patients should initially receive i.m. injections. Further, because orally administered drugs are metabolized in the gut, as well as during their first pass through the liver, less than 50% may reach the systemic circulation for ultimate availability at the intended brain sites. 

Suppositories are pharmaceutical dosage forms intended for administration of medicine via the rectum, vagina, or urethra that melt, soften, or dissolve in the body cavity. Rectal and vaginal suppositories are most common but urethral suppositories are sometimes used. Suppositories are indicated for administering drugs to infants and small children, severely debilitated patients, those who cannot take medications orally, and those for whom the parenteral route might be unsuitable. Suppositories are used to administer drugs for either systemic or local application. Local applications include the... 

Sigal MV Jr, Buchanan DJ, Robinson CS. 1954. Studies on phosphorus intoxication. II. Fate of orally administered choline in dogs with damaged liver. American Medical Association Archives of Industrial Hygiene and Occupational Medicine 9 142-147. 

The intrinsic kinetic properties of the victim drug also influence the potential clinical consequences of an interaction. For orally administered medications that undergo significant presystemic extraction, impairment of clearance by a CYP inhibitor may produce increases in bioavailability (reduced presystemic extraction) as a consequence of reduced clearance. The effects may be particularly dramatic for CYP3A substrates (such as triazolam, midazolam, or buspirone) that undergo both hepatic and enteric presystemic extraction. As an example, coadministration of the CYP3A inhibitor ketoconazole with triazolam produced very large increases in area under the plasma concentration-time curve... 

The bioavailability of vaginally administered misoprostol is 3 times higher than that of orally administered misoprostol, which may explain why intravaginal misoprostol has been reported to be more effective than oral misoprostol for medical abortion. 

The biodrug concept involves the use of orally administered recombinant microorganisms as a new drug delivery route to prevent or treat various diseases. The potential medical applications are numerous and can be classified in terms of bioconversion or production of active compounds. Validation studies have yet been conducted in animals (and even sometimes in human being), as described below and summarized in Table 1. 

Clomiphene citrate (Clomid) is an orally administered nonsteroidal agent widely used for treatment of infertility. Visual side effects associated with clomiphene therapy include nonspecific blmring of vision and various entop-tic phenomena, including flashes of light, scintillations, heat waves, and prolonged afterimages. The symptoms can occur as early as several days after treatment is started and usually disappear within several days to several weeks after treatment is discontinued. Cases have been reported, however, in which patients remained symptomatic from 2 to 7 years after discontinuing the medication. 

After approx. 10 days, newborn jaundice subsides without any further consequences. Bilirubin also acts as an antioxidant and can thus provide protection from oxygen radicals, if necessary. Peripartal complications can, however, reinforce or prolong this state. This may occur in infantile hypothyroidism or when medication is administered directly to the infant as well as via breast milk (particularly when bilirubin is displaced from its albumin binding by drugs). In more pronounced jaundice, phototherapy and an increase in the oral intake of fluids may be advisable. (44, 45, 48,53,58, 64)... 

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