ADVERSE DRUG REACTIONS KEY POINTS

Adverse drug reactions (ADRs) may be augmented (Type A) or bizarre ( Type B); Type A reactions may be due to excessive or unwanted pharmacological effects, withdrawal reactions, delayed effects or failure to individualize dosage;

Many Type B reactions have an immunological or genetic basis and are normally unrelated to dosage.At the time of marketing a new drug, not all ADRs may be known;Factors Influencing ADRs include multiple drug regimens, multiple disease states, type of drug, route, formulation and dosage, age, gender, race and extent of compliance with medicines;

Causality of ADR can be categorized using set criteria;

The Yellow Card scheme is used by the CSM as one type of postmarketing surveillance;

Pharmacists can play an important role in identifying, documenting, monitoring and preventing ADRs in their routine practice;

Pharmacists should report suspected ADRs to the CSM or to regional monitoring centres on Yellow Cards;

Hospital pharmacists should report particularly ADRs to drug initiated and monitored within hospital specialist units;

Community pharmacists should report particularly ADRs to non-prescription medicines and herbal product.

MEDICINES INFORMATIONKEY POINTS

All pharmacists have a responsibility to provide information and advice about any medicine supplied by them or under their authority. It is vital that this information should be reliable, accurate and up to date;

Pharmacists need to be familiar with the key reference sources that are useful for common types of questions ( e.g. drug interactions, side-effects, drug use in pregnancy) and to be able to critically appraise and evaluate the information found. A systematic search strategy should be adopted when dealing with enquiries or clinical problems;

Remember, the worst question is the one that is not asked. Continue to question drug therapy issues as this can only enhance your experience, expand your knowledge and, most importantly, benefit your patients, Never settle for poor or inadequate answers.

The Evaluation of MedicinesKey PointsPharmacists are involved extensively in evaluating medicines, their use and information about medicines;The Committee on safety of Medicines (CSM) requires granting a product licence for a new drug;Clinical trials take place in three phases : Phase I- determines the basic toxicity and tolerability,

Phase II establishes efficacy and confirms the dosage,Phase III determines safety and efficacy on a larger sample;

Postmarketing studies enable comparisons to standard therapies, establishment of new indications and are required to establish many adverse reactions to drugs;

Evidenced-based medicine seeks to identify the available evidence to answer specific clinical questions, critically appraise if and apply it to individual patients or to populations;There are several organizations in the UK providing evaluated evidence of the efficacy, safety and economy of medicines;Drug utilization review (DUR) assesses the patients of drug use un particular clinical situations;

Drug Use Evaluation ( DUE) relates drug use to patient outcome;Methods for studying DUR and DUE include the use of drug purchase records, drug issue records; prescription records, medical records and specifically designed recording systems;Patient questionnaire methods can provide useful information about the use of non- prescription drugs.

PHARMACOECONOMICSKey Points

Pharmacoeconomics applies the principles of economic evaluation to pharmacy;Some of the basic economic concepts are scarcity, choice and opportunity cost which can be applied to the medical field;There are recognized steps in carrying out any economic evaluation;

Applications of the principles of costing may be straightforward but can be difficult, especially when applying discount;Cost-minimization analysis (CMA) is applied when outcomes are the same and relative cost is the variation;Cost-effectiveness analysis ( CEA) is applied when both outcomes and cost can vary and is frequently applied in pharmacy and medicine;

Cost-utility analysis ( CUA) involves the concept of quality of life to assist in informing resource allocation;

Cost-benefit analysis (CBA) is complex, but should allow informed resource allocation within the whole economy, not just in health;

CBA may use implied values, human capital or willingness-to-pay-methods;

To accommodate decision-taking in health care, modelling and sensitivity analysis methods can be used;

Any published pharmacoeconomics analysis requires careful appraisal to ensure the internal and external; validity.

Formularies and GuidelinesKey Points

A formulary is a list of drugs which are recommended and available for prescribing;

A formulary may contain prescribing policies or treatment protocols, which detail the use of drugs in specific medical conditions;

A clinical guidelines is a series of systematically developed statements to assist practitioner and patient decision about appropriate health care for specific clinical circumstances;

Formularies, clinical guidelines and prescribing policies are tools used to promote rational and cost-effective prescribing;

Compiling a formulary or guideline is a valuable educational exercise;

Pharmacists should work with others to compile formularies and guidelines;

Drugs are selected for inclusion in a formulary on the basis of efficacy, toxicity, patient acceptability and cost;

Use of a formulary containing a restricted number of drugs may reduce the incidence of adverse drug reactions, interactions, and lack of efficacy;

For a formulary to be accepted, there should be widespread consultation on its content;

A formulary should be easy to se and professionally presented and revised at least every 2 years;

A formulary management system is required to provide systems for considering the inclusion of new drugs, deleting drugs and supplying non-formulary drugs;

Information should be provided to prescribers on their adherence to a formulary to encourage its use;

Prescribing data can be useful both in developing a formulary and feeding back on performance;

Recommendations in clinical guidelines are often graded according to the strength of the evidence on which they are based;

Ideally a mixture of methods should be used to encourage the use of formularies and guidelines.

Responding to SymptomsKey Points

Pharmacists are recognized and used as sources of advice on patients symptoms and medicine;Medicines are increasingly being re-regulated to allow pharmacy sale, thus encouraging self-medication;

A wide mix of skills is required by the pharmacist to respond competently to symptoms presented by patients;

Open questions are best in the early stages of finding out about symptoms, using closed questions to seek clarification of specific aspects;

A process of structured questioning should be used to ensure adequate collection of available information and determine whether a patients symptoms represent a self-limiting condition or the possibility of a more serious illness which requires a medical opinion and referral to a doctor;

Various mnemonics are useful to assist the questioning process;

Patients may require professional assistance in the choice of OTC medicines;

Non-drug treatment should be offered where appropriate, including lifestyle advice;

A quiet area where privacy and confidentiality can be provided should be available;

Particular care is required when dealing with symptoms in young children, pregnant women, the elderly and patients with some chronic diseases;

Duplication of OTC and prescribed medicines can sometimes have serious consequences;There are a number of clinically significant drug interaction involving OTC medicines;Pharmacists must be alert to the possibility of misuse of OTC medicines.

CounsellingKey Points

Counseling is an important part of the role of the pharmacist and there are many opportunities for counseling;Counseling is for the benefit of patients and purchasers of medicines;The importance of counseling is recognized in many official documents;

The prescription is a useful guide to possible counseling needs;

The extent to which patients should be told about side-effects will vary from one patient to another;

Counseling should be used to reinforce the label and compliances and warn against the potential for interactions;

Some groups can be identified as requiring special counseling- the elderly, where there have been previous problems, parents of ill children;

It may be necessary to limit the amount of information given during counseling to avoid confusion and meet patients need;

Checking is important in ensuring the effectiveness of counseling;A busy setting is a barrier to effective communication;

Patients are becoming more aware that pharmacists can give valuable advice;Counseling is not a lecture patients must be given the opportunity to ask questions.