LIQUID DOSAGE FORMS PART I

 All liquid dosage forms are dispersed systems in which medical substance (the internal phase) is dispersed uniformly though-out the external phase. Medical substances in liquid dosage form can be in the different aggregate states: solid, liquid and gas.

Physical and chemical systems:  real solutions  colloid solutions  suspensions  emulsions  infusions, decoctions, extracts and other.

Solution is a homogeneous mixture composed of two or more substances. In mixture, solute is dissolved in another substance, known as a solvent. homogeneous mixturesolutesolventhomogeneous mixturesolutesolvent

Liquid dosage forms can be classified by medical aplication:  for internal use - ad usum іnternum  for external use - ad usum externum  for injection - pro іnjectіonіbus.

Liquid dosage forms for internal use name usually mixtures (from the Latin word of mіxturae - to mix up), the disperse phase - water only. They are measured out to the patients independently by spoons (table (soup)-spoon - 15 ml, dessert-spoon - 10 ml, tea-spoon – 5ml.).

By composition  Simple- solutions which include only one substance.  Multiple- solutions which include a few ingredients. By nature of solvent.  Hydrogen's  non-aqueous (alcoholic, glycerin, oily).

BASIC TECHNOLOGICAL OPERATIONS FOR PREPARATION LIQUID DOSAGE FORMS

Preparation of liquid dosage forms consists of the followings stages:  1.Selection of small bottles and corks.  2.Weighting of medical substances.  3.Measurement of solvent.  4.Dissolution.  5. Percolation or filtration.  6.Packing.

Nomenclature of the concentrated solutions which more frequent use for preparation of mixtures  5 % solution (1:20) sol. Natrii hydrocarbonatis  10 % solutions (1:10) are sol. Natrii benzoates, sol. Coffein natrii-benzoatis.  20 % solutions (1:5) are sol. Natrii bromidi, sol. Kalii bromidi, sol. Natrii iodidi, sol. Kalii iodidi, sol. Natrii chloridi, sol. Kalii chloridi, sol. Calcii chloride, sol. Hexamethylentetramini, sol. Cloralii hydrati, sol. Natrii salicylati.  25 % solution (1:4) sol. Magnii sulfati.

For example, it is necessary to prepare 1 L 20% solution of Kalii bromidi. All calculations can be conducted by two methods: account the density of this solution account the coefficient of increase of volume

Account the coefficient of increase of volume : Quantity of water for preparation of the concentrated solutions, can be expect using the coefficient of increase of volume. The coefficient of increase of volume (CIV) is coefficient, which shows an increase of the volume of solution at dissolution of a 1,0 gram of solid substance. For Kalii bromidi CIV evened 0,27. Then 200,0 gr of Kalii bromidi at dissolution will occupy a volume 54 ml. V= 0,27*200,0 = 54 Consequently, for a receipt to a 1 litre of a 20% solution it is necessary to take 946 мл of the cleared water =946ml