Capsules liquid dosage forms preparation

Because it is bitter, this antibiotic is administered orally cither in capsules or as the palmitatc e.ster. Chloramphenicol palmitate is insoluble in water and may be suspended in aqueous vehicles for liquid dosage forms. The ester forms by reaction with the hydroxyl group on C-3. In the alimentary tract, it is hydrolyzed slowly to the active antibiotic. Chloramphenicol is administered parenterally as an aqueous suspensiuti of very fine cry.stals or as a solution of the sodium salt of the succinate ester of chloramphenicol. Sterile chloramphenicol sodium succinate has been used to prepare aqueous. solutions for intravenous injection. 

The label should indicate if a tablet or capsule contains one, two or three adult standard dosage forms of the drug. Liquid preparations should indicate similarly if there is one, two or three adult standard dosage forms per teaspoon of the preparation. Buffered salicylate products must have at lezist 1.9 milliequiveilent of acid neutralising capacity per adult dosage unit. 

In the United States, Echinacea is marketed primarily in oral dosage forms (tablet, capsule, and liquid) as an immune stimulant used to help with the symptoms of upper respiratory infections (URIs). It has also been promoted as a general immune stimulant to help fight various other infections. Topical preparations are also available for treatment of wounds and inflammatory skin conditions. 

A less frequent but nonetheless interesting problem arises in the chemical modification of liquid, or low-melting, active principles in solid prodrugs, suitable for tablet or capsule preparation. Indeed solid dosage forms are still the most widely used for the administration of medicines, as well for patient acceptability and convenience for product stability and ease of manufacture. Their preparation implies that the active principle can itself be handled as a stable solid, an objective that is usually attained by one of the following strategies formation of a salt or a molecular complex, formation of a crystalline covalent derivative, introduction of symmetry. 

Cascara sagrada is available in tablets, capsules, liquids (fluid extracts), and syrups. Fluid extracts are more reliable than the solid dosage forms. Aromatic cascara fluid extract is less bitter and less active than cascara sagrada fluid extract because of the use of magnesium oxide in its preparation (Curry, 1986). Cascara tea is available, but has an extremely bitter taste (Tyler, 1994). 

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. 

Stability is one of the main advantages of solid dosage forms compared to liquid ones. There is no need for preservatives or other excipients (e.g. antioxidants) to enhance stability. Capsules, cachets and powders can be prepared with few and safe excipients. Tablets, capsules... 

Normally hard capsules are swallowed whole, but when they need to be administered to infants, pharmacy-prepared capsules may be opened before administration and the contents mixed with a small amount of suitable liquid or soft food. However, solid dosage forms that provide flexible dosing, such as fast dissolving granules (sprinkles) and uncoated mini-tablets may be preferable for paediatric patients because taste and smell can be masked and therefore compliance may improve [3]. 

Most industrially manufactured herbal medicinal products are oral dosage forms. Liquid preparations (fluid extracts, tinctures) have advantages as to dose flexibility but an unacceptable taste can be a problem in clinical practice. The latter can be circumvented by using solid oral dosage forms containing a dry extract of the herbal medicine. Tablets and capsules with pulverized herbal active substances are also available commercially. Some herbal medicines have to be taken as loose powders. A tea can be prepared from pulverized herbal medicines, either l(X)se or in teabags, or from an instant herbal tea [4, 5]. 

However, these modification strategies may not be possible to apply to modified-release preparations. Questions such as the following should be answered is it possible to spht the dosage form without destroying its function Is it possible to mix the content of a capsule without grinding Can the dosage form be modified into a liquid preparation And if so, should the dose or dose frequency be adjusted ... 

The British Pharmacopoeia [2] gives requirements for the dissolution rate of oral suspensions in the general monograph for Unlicensed Medicines . These quality requirements are similar to the advice of the Ph. Eur. for capsules and tablets. The dissolution rate of an oral suspension, being prepared in pharmacies for instance for patients with swallowing problems or for children, and how it compares to the comparable licensed oral dosage form, is an important consideration when designing such liquid medicines. 

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