Oral administration liquid dosage forms

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. 

Absorption after oral administration is rapid, consistent, and nearly complete when given in solution or as immediate-release dosage form. Theophylline can be detected in blood within 10 to 15 min after ingestion of a liquid formulation, and food does not have any major influence when administered with these dosage forms. Thus, oral bioavailability can be assumed as 100% in these cases. For oral immediate-release dosage forms, peak serum concentrations are reached 1 to 2 h after administration. ... 

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. 

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. 

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

Powders for oral administration that are reconstituted in their market container, however, have an additional possibility of interaction between the packaging components and the reconstituting fluid. Although the contact time will be relatively short when compared to the component/dosage form contact time for liquid-based oral dosage forms, it should still be taken into consideration when the compatibility and safety of the container closure system are being evaluated. 

Several types of containers are available for discussing oral administration. Most of these have been discussed in some sections above. These containers include the polyethylenes (e.g., HDPE and LDPE) and the PPs used for solid oral dosage forms as multiple-unit containers. Others include PVC, PVdC, and Aclar intended for solid oral dosage forms as a single-unit container. The oral liquids are contained in PET- and PETG-type containers. 

A medication available only as a solid dosage form, may be prepared as an extemporaneous liquid (e.g., suspension) or it may be modified for oral use, for example, by crushing. As mentioned previously, a sustained-release product should not be crushed or chewed. For a solid, non-sustained-release medication, the product can be crushed and mixed with a small amount of food just prior to administration. Examples of foods that may be used for mixing include applesauce, yogurt, or instant pudding, but the medication should not be added to an entire dish of food or to infant formula, because the infant or child may not eat/drink the entire portion and thus not receive the total amount of medication. 

Oral dosage forms available for administration to animals include oral solutions, liquids, suspensions, gels, pastes, capsules, tablets, ruminal boluses, powders and granules for addition to feed, soluble powders for... 

Advantages. Phenobarbital has linear and predictable pharmacokinetics. If the dose is doubled, the resulting serum concentrations double. Multiple dosage forms (e.g., oral solid, oral liquid, intramuscular, and intravenous) are available, so the route of administration can be tailored to patient needs, including emergent conditions. It is the most inexpensive AED. 

Table 7.5 Bioavailability parameters for theophylline after oral administration of 300 mg dose through liquid or capsule dosage forms to 14 subjects ...

---