POSOLOGY – PHARMACEUTICS II (Dispensing Pharmacy) D. Pharm 2nd year PDF Notes




Posology is a branch of medicine which deals with doses or quantity of drugs which can be administered to produce the required pharmacological actions.


       1. Paracetamol:

               Maximum daily dose upto 4grams.

                Route of administration – orally in divided doses.

                Use – Anti-pyretic

       2. Ampicillin:

                Maximum daily dose                      -1 to 6grams

                Route of administration      -Oral daily in divided doses.

                Use: Broad spectrum antibiotic

       3. BCG Vaccine:

               Single Dose                                      -0.1ml

               Route of administration                   -Prophylactic by intra muscular

               Category                                          -Active immunizing agent

Formulae to calculate children dose:

Response of drugs may vary from one patient to another patient. The dose for children can be calculated from the adult dose by using age, Body weight and surface area. Infants require lesser dose than the adult. 

I. Depending on age:

a) Young’s formula:

Child‘s dose          =   Age in years     X   adult dose

                                 Age in years +12          

This formula is suitable to calculate the dose for a child below 12 years.

b) Dilling’s formula:

        Child dose          =  Age in years           X     adult dose


This formula is suitable to calculate the dose for a child between 12 to 20 years.

c) Fried’s formula:

         Child dose         =   Age in months       X      adult dose


This formula is suitable to calculate the dose for infants.

II. Depending of body weight:

 Clark’s formula

     Childs’s dose   =    Weight in pounds  X adult dose


III. Based on surface area:

          Child dose   =   Body surface area of child       X       Adult dose

                                    Body surface area of an adult

 For PDF Notes Click Here

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