Essential medicines

DefinitionEssential medicines are those that satisfy the priority health care needs of the populationCriteria for Selection of Essential MedicinesEssential medicines are selected with due regard to disease prevalence, evidence on efficacy and safety, and comparative cost-effectiveness

Essential Medicines Essential medicines are intended to be available within the context of functioning health systems at all times in adequate amounts, in the appropriate dosage forms, with assured quality, and at a price the individual and the community can afford.

A global concept

The concept of essential medicines is forward-looking. It incorporates the need to regularly update medicines selections to reflect new therapeutic options and changing therapeutic needs; the need to ensure drug quality; and the need for continued development of better medicines, medicines for emerging diseases, and medicines to meet changing resistance patterns.

Rational Therapeutics “Poisons in small doses are the best medicines and useful medicines in too large doses are poison’s”

William Withering.

a. Whether medication is at all required by the patient?

b. What alteration in the condition of the patient is expected to be achieved?

c. Can that particular drug be administered in a manner that right concentration can be attained in the right place at the right time for the right duration?

d. What side effects does the drug have and how harmful they can be?

e. Do the likelihood of benefit ad its quantum appear to out-weigh the possible damage and its extent?

Communication skills / reassurance

Compliance; Obedience to take the treatment

Cost effectiveness

a. Economic aspects of therapeutics should be included in all medical training programmes.

b. Economic aspects should be included in all discussion in the literature concerning recent therapeutics.

c. Journals should require drug advertisements to contain the prices of the drugs advertised.

d. Publications advertising proprietary advertisement should be encouraged to include the prices of the drugs in the information they supply.

e. Information on drug costs & on the virtues of basic cheap drugs vis-à-vis their new competitors, should de widely disseminated to practicing doctors by appropriate committees in the Ministry of Health.

PLACEBOS

Placebo means “I will please”. It is used to benefit or please a patient, not by any pharmacological means but by psychological means. A placebo is a vehicle for cure by suggestions, and surprisingly often successful.

BIO-AVAILABILITY

Definition Bioavailability is defined as the

fraction of un changed drug, reaching the systemic circulation following administration by any route.

Medical/ Treatment History

1. Past/Concurrent illnesses

2. Drug History

Drug Interactions

Reduced plasma concentration of cimetidine

RifampicinCimetidine

EffectDrug interactingDrug affected

PotentiationAspirin,Heparin

Hypotension, heart failureBeta-blockersVerapamil

Severe hypertension especially with non selective ones

AdrenalineBeta-blockers

HyperkalaemiaACE inhibitors (captopril etc) NSAIDS, K.+ supplements

Potassium-sparing diuretics

Large I.V dose can precipitate arrhythmias

FurosemideDigoxin

Patient Education/Informational needs of the Patient

Dosage Schedule

Method of Administration

Precautions to be taken

Side Effects of drugs used

Storage instructions

Summary of Rational Prescribing Rules

The doctor must take the following considerations into account before prescribing drugs to the patients;

• Is the drug therapy really necessary?• Is the drug dose appropriate?• Is the drug formulation (tablet, injection, syrup or

suppository) appropriate?• Is the fixed combination of drugs logical?• Is the patient’s compliance to the drug adequate?• Is the drug cost-effective?• Whether the drug interacts with substances that the

patient may be taking?• When is the drug to be withdrawn?

THERAPEUTIC FAILURE

Failure to achieve or maintain desired therapeutic effect of a drug is known as therapeutic failure.

CAUSES OF THERAPEUTIC FAILURE

a. Poor Compliance b. Factors affecting Biotransformationc. Factors affecting Bioavailabilityd. Drug Interactionse. Drug Tolerancef. Quality of Drugsg. Inappropriate Indicationh. Untoward effects