Dosage parenteral

The USP recognizes three forms of water for parenteral dosage forms. Water for injection is prepared by reverse osmosis or distillation, which... 

It is generally assumed that adequate vitamin levels in humans can be obtained through a balanced diet. However, ongoing studies continue to indicate that the majority of the U.S. population is not receiving even the RDA through diet. Supplementary vitamins are thus provided for fortification of foods (20) and as oral or parenteral dosage forms. 

In the human market, oral and parenteral dosage forms are prepared from the crystal. However, because of the extremely high potency, more dilute (0.1—10%) forms are avabable. These include dilutions with mannitol, triturations on dicalcium phosphate or resins, and spray-dried forms. Prices for these forms are driven by that of the crystal, which in early 1996 was ca 9.50/gram (95). Prices for the vitamin have risen during the first half of the 1990s. However, Htde growth in price beyond inflation is anticipated. 

Oral or Parenteral Drug Dosages Based on Weight... 

The dosage of an oral or parenteral drug may be based on the patient s weight. In many instances, references give Hie dosage based on Hie weight in kilograms (kg) raHier than pounds (lb). There are 2.2 lb in 1 kg. 

When electrolytes are administered parenterally, the dosage is expressed in milliequivalents (mEq), for example, calcium gluconate 7 mEq IV When administered orally, sodium bicarbonate, calcium, and magnesium dosages are expressed in milligrams (mg). Potassium liquids and effervescent tablet dosses are expressed in milliequivalents capsule or tablet dosses may be expressed as milliequivalents or milligrams. 

P2-Agonists cause airway smooth muscle relaxation by stimulating adenyl cyclase to increase the formation of cyclic adenosine monophosphate (cAMP). Other non-bronchodilator effects have been observed, such as improvement in mucociliary transport, but their significance is uncertain.11 P2-Agonists are available in inhalation, oral, and parenteral dosage forms the inhalation route is preferred because of fewer adverse effects. 

If the areas under the curves are denoted by A, then (based on equal dose) All/Al is the fraction absorbed by oral route. Alll/All is the fraction efficiency of the solid dosage form. The reason for this latter is, of course, that the solid dosage form has to dissolve before the drug contained in it is available for absorption. It is the latter ratio that is important to the investigating pharmaceuticist, and therefore the outcome of the parenteral form is actually not a consideration from a formulation point of view. It is critical overall and if it is low, it may, at the point of parenteral data acquisition, be advisable to stop the program and evaluate the possibility of derivatives that would give better availability. 

In contrast, parenteral suspensions have relatively low solids contents, usually between 0.5 and 5%, with the exception of insoluble forms of penicillin in which concentrations of the antibiotic may exceed 30%. These sterile preparations are designed for intramuscular, intradermal, intralesional, intraarticular, or subcutaneous injection. Syringeability is an important factor to be taken into consideration with injectable dosage forms. The viscosity of a parenteral suspension should be sufficiently low to facilitate injection. Common suspending vehicles include preserved isotonic saline solution or a parenterally acceptable vegetable oil. Ophthalmic and optic suspensions that are instilled into the eye/ear must also be prepared in a sterile manner. The vehicles are essentially isotonic and aqueous in composition. The reader should refer to Chapter 12 for further discussion on parenteral products. 

The pharmaceutical industry directs considerable effort toward maximizing the usefulness and reliability of oral dosage forms in an effort to minimize the need for parenteral administration. Factors that... 

In recent years, parenteral dosage forms, especially IV forms, have enjoyed increased use. The reasons for this growth are many and varied, but they can be summed up as (a) new and better parenteral administration techniques, (b) an increasing number of drugs that can be administered only by a parenteral route, (c) the need for simultaneous administration of multiple drugs in hospitalized patients receiving IV therapy, (d) new forms of nutritional therapy, such as intravenous lipids, amino acids, and trace metals, and (e) the extension of parenteral therapy into the home. 

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