RATIONAL DRUG THERAPY

Drug selection while treatment must be based on the following.

1. Relevance to disease - Indicated in the treatment of prevalent diseases.

2. Efficacy and safety - Based on the objective results from adequate pharmacological studies including atleast expanded phase (II). clinical trials and / or additional phase (III). studies.

3. Quality.

4. Cost-of treatment regime (not just the unit cost).

5. Appropriateness to the capability of medical personnel at different levels of health care-The level of expertise required to prescribe, administer and monitor safety and adverse effects of single drug or group of drugs in the therapeutic category must be considered. Consideration should be given to the to the competence of local personnel in making the correct diagnosis.

6. Local health problems-The influence of concomitant, locally prevalent diseases or conditions on pharmacokinetic and pharmacodynamic parameters modifying therapeutic response have to be considered in making the selection eg. malnutrition, liver disease.

7. Benefits / Risk ratio - when several comparable drugs are available for the same therapeutic indication it is necessary to select the one which provides the most favorable benefit/risk ratio.

8. Preferential factors for evaluating therapeutically equivalent drugs - when two or more drugs are therapeutically equivalent preference should be given to :-

(A) The drug most thoroughly investigated and therefore the best understood with respect to its beneficial properties and limitations.

(B) The drug which is clinically appropriate for more than one disease.

(C) The drug with the most favorable pharmacokinetic properties eg., to improve the compliance to minimize risk.

(D) The drug that are in a dosage form that is easy for the health staff to dispense easily and safely administer to the patient.

(E) The drugs that are easy for the patient to take or with the broadest acceptability.

(F) The drugs, pharmaceutical products and dosage forms with favorable stability under anticipated local conditions for which storage facilities exist.

(G) The drugs for which reliable local manufacturing facilities exist.

9. In the majority of cases the drugs should be formulated as single compounds. Fixed-ratio combination are only acceptable when-

(A) The clinical value of simultaneous use of more than one dose is documented.

(B) The therapeutic benefit of the combination is greater than the sum of each of the individual components.

(C) The combination is safer than the use of an individual drug.

(D) The cost of the combination product is less than or equal to the total cost of the individual products.

(E) The compliance is improved.

(F) The combination must be such that sufficient quantities to meet the needs of the majority of the population can be maintained.

10. Periodic review of druglist - Yearly or whenever necessary to incorporate significant new therapeutic advances and selected drugs.

(A) Generally new drugs should be introduced only if they offer distinct advantages over previously selected drugs.

(B) If on the basis of new information, drug already on the list are found to no longer posses a favorable benefit / risk ratio, they should be replaced by drugs with the higher benefit/risk ratio.

11. International Non-proprietary names (INN ; generic names) should be used for drugs.