Administration liquid dosage forms

If a liquid dosage form of a medication exists, it would seem rational to use this dosage form for administration through a feeding tube. Although such a decision may decrease the potential for tube clogging, it may in some instances decrease tolerability of the medication administration. Sorbitol is an excipient found in many liquid medications in amounts sufficient to cause diarrhea. If diarrhea secondary to sorbitol in a liquid medication is suspected in a patient on EN, contact with the manufacturer to ascertain sorbitol content may be necessary. 

Oral Administration. Oral administration is the preferred route of administration. There is a general consensus among pediatricians and parents that children younger that 5 years of age have great difficulty with, or are unable to swallow, a solid oral dosage form. Manufacturers, therefore, have developed liquid formulations for many of the commonly used pediatric products. The liquid dosage form, however, is not free of problems. Liquid products are often unstable and have short expiration dates accurate measurement and administration of the prescribed dose is also a problem, especially in infants. 

Adjustments in pH lo maintain water solubility cun sometimes lead lo chemical stability problems. An example is indomelhacin (HA acid pK ,4.S). which is unstable in alkaline media. Therefore. Ihc preferred oral liquid dosage form is a suspension buffered at pH 4 to 5. Because this is near the drug s pK . only. W f will be in the water-soluble form. There is a medical indication requiring intravenous administration of indomelhacin to premature infants. The intravenous dosage form is the lyophilized (freeze-dried) sodium salt, which is reconstituted just prior lo use. 

Despite the well known advantages of controlled release dosage forms, conventional dosage forms are still most widely used probably because they cost less to manufacture. More than three quarters of all drug formulations are made for oral administration. Oral dosage forms such as tablets, capsules, and liquids are still most popular. Since tablet is one of the most widely used dosage forms and its preparation requires incorporation of polymers, we will focus on polymers used in tableting process. 

For rectal administration an active substance can be formulated into a suppository (solid dosage form) or in an enema (liquid dosage form). The desired miset of action is important for the choice. For a rapid onset an enema is preferable, because a suppository base has to melt or to dissolve first. A suppository may be preferred because its use is easier and more patient-friendly. An enema is the best choice when a local effect over a large surface is desired, for instance in the treatment of ulcerative colitis. From a practical viewpoint an enema can be prepared faster, but is more sensitive to chemical degradation, due to the presence of water. 

Quick dissolving pharmaceutical oral films/wafers are an attractive route of administration because they dissolve or deaggregate spontaneously in the oral cavity, resulting in a solution or suspension without water. Effectively it is a solid-dosage form providing the convenience of a liquid-dosage form. The perception of using thin films... 

Oral administration of the peptide drug antide in a liquid dosage form showed no detectable concentration of the drug in plasma at all. When a thiolated chitosan was introduced into the formulation, however, an improved uptake of the drug was fotmd. The absolute and relative bioavailability of these formulations were calculated to be 1.1% and 3.2% increased, respectively [74]. 

The oral administration of liquid dosage forms of suitable consistency and with sustained release characteristics may provide a means of improving the compliance of geriatric patients who experience difficulties in swallowing conventional solid dosage forms. 

Liquids and Suspensions. Most liquid formulations are not packaged in unit-dosage form. Therefore, before administration, the proper amount of medication to be taken for each dose must be measured. This additional requirement may compound any difficulties a patient may have in following a prescribed schedule. Patients suffering from visual impairment, arthritis, or tremors associated with neurological disorders are particularly likely to become frustrated with this type of formulation. Visual impairments make it difficult, if not impossible, for many elderly patients to measure the prescribed amounts of medication accurately. Impaired dexterity, owing to tremors or arthritis, may have effects on a patient s ability to hold both a spoon and a bottle at the same time while pouring out the desired amount of liquid. 

Oral (PO = per os) By the mouth. Oral administration is the most common route employed for a variety of dosage forms tablets, capsules, liquids, suspensions. The major site of absorption is the small intestine. Alcohol is absorbed from the stomach. 

After the administration of a syrup and tablet dosage form of a drug, the following data was obtained. What is the AUC of the liquid relative to the solid dosage form ... 

A changing an adult oral dosage form to a liquid formulation for administration to a paediatric patient... 

Protein-based drugs have been formulated mainly as stable liquids or in cases where liquid stability is limiting as lyophilized dosage forms to be reconstituted with a suitable diluent prior to injection. This is because their delivery has been limited primarily to the parenteral routes of intravenous (IV), subcutaneous (SC), or intramuscular (IM) administration. There are a few drugs that have been developed for pulmonary delivery, such as rhDNase (Pulmozyme ) and an inhalable formulation of insulin (e.g., Exubra ). However, even such drugs have been formulated as either liquid or lyophilized or spray-dried powders. This chapter will focus only on excipients that are applicable to liquid and lyophilized protein formulations. 

For liquid (e.g., solution, suspension, elixir) and semisolid (e.g., creams, ointments) dosage forms, a change to or in polymeric materials (e.g., plastic, rubber) of primary packaging components, when the composition of the component as changed has never been used in a CDER-approved product of the same dosage form and same route of administration. For example, a polymeric material that has been used in a CDER-approved topical ointment would not be considered CDER-ap-proved for use with an ophthalmic oinhnent. 

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