Pharmacy and therapeutic committee
Organization, functions, Policies of the pharmacy and therapeutic committee in
including drugs into formulary, inpatient and outpatient prescription, automatic stop order, and emergency drug list preparation.
b) Drug information services
Drug and Poison information centre, Sources of drug information, Computerised services, and storage and retrieval of information
Drug Information Services Division
1. Provide drug information on drugs and drug therapy to doctors, nurses, medical and nursing students and the house staff.
2. Maintain the drug information center.
3. Prepare the hospital’s pharmacy newsletter.
4. Maintain literature files.
Departmental Services Division
1. Control and dispense intravenous fluids.
2. Control and dispense controlled substances.
3. Coordinate and control all drug delivery and distribution systems.
DRUG HISTORY AND THERAPEUTIC PLAN
In the twenty-first century, a reliable drug history involves questioning the patient (and sometimes family, neighbours, other physicians, etc.). What prescription tablets, medicines, drops, contraceptives, creams, suppositories or pessaries are being taken? What over-the-counter remedies are being used including herbal or ‘alternative’ therapies? Does the patient use drugs socially or for ‘life-style’ purposes? Have they suffered from drug-induced allergies or other serious reactions? Have they been treated for anything similar in the past, and if so with what, and did it do the job or were there any problems? Has the patient experienced any problems with anaesthesia? Have there been any serious drug reactions among family members?
The prescriber must be both meticulous and humble, especially when dealing with an unfamiliar drug. Checking contraindications, special precautions and doses in a formulary such as the British National Formulary (BNF) (British Medical Association and Royal Pharmaceutical Society of Great Britain 2007) is the minimum requirement. The proposed plan is discussed with the patient, including alternatives, goals, possible adverse effects, their likelihood and measures to be taken if these arise. The patient must understand what is intended and be happy with the means proposed to achieve these ends. (This will not, of course, be possible in demented or delirious patients, where discussion will be with any available family members.) The risks of causing harm must be minimized. Much of the ‘art’ of medicine lies in the ability of the prescriber to agree to compromises that are acceptable to an individual patient, and underlies concordance (i.e. agreement between patient and prescriber) with a therapeutic plan. Prescriptions must be written clearly and legibly, conforming to legal requirements. Electronic prescribing is currentlynbeing introduced in the UK, so these are changing. Generic names should generally be used (exceptions are mentioned later in the book), together with dose, frequency and duration of treatment, and paper prescriptions signed. It is prudent to print the prescriber’s name, address and telephone number to facilitate communication from the pharmacist should a query arise. Appropriate follow up must be arranged.
FORMULARIES AND RESTRICTED LISTS
Historically, formularies listed the components of mixtures prescribed until around 1950. The perceived need for hospital formularies disappeared transiently when such mixtures were replaced by proprietary products prepared by the pharmaceutical industry. The BNF summarizes products licensed in the UK. Because of the bewildering array, including many alternatives, many hospital and primary care trusts have reintroduced formularies that are essentially restricted lists of the drugs stocked by the institution’s pharmacy, from which local doctors are encouraged to prescribe. The objectives are to encourage rational prescribing, to simplify pur chasing and storage of drugs, and to obtain the ‘best buy’ among alternative preparations. Such formularies have the.advantage of encouraging consistency, and once a decision
has been made with input from local consultant prescribers they are usually well accepted.
SCIENTIFIC BASIS OF USE OF DRUGS IN
The scientific basis of drug action is provided by the discipline of pharmacology. Clinical pharmacology deals with the effects of drugs in humans. It entails the study of the interaction of drugs with their receptors, the transduction (second messenger) systems to which these are linked and the changes that.they bring about in cells, organs and the whole organism..These processes (what the drug does to the body) are called ‘pharmacodynamics’. The use of drugs in society is encom passed by pharmacoepidemiology and pharmacoeconomics both highly politicized disciplines!
Man is a mammal and animal studies are essential, but their predictive value is limited. Modern methods of molecular and cell biology permit expression of human genes, including those that code for receptors and key signal transduction elements, in cells and in transgenic animals, and are revolutionizing these areas and hopefully improving the relevance
of preclinical pharmacology and toxicology. Important adverse effects sometimes but not always occur in other species. Consequently, when new drugs are used to treat human diseases, considerable uncertainties remain. Early-phase human studies are usually conducted in healthy volunteers, except when toxicity is inevitable (e.g. cytotoxic drugs used for cancer treatment, see Chapter 48).
Basic pharmacologists often use isolated preparations, where the concentration of drug in the organ bath is controlled precisely. Such preparations may be stable for minutes to hours. In therapeutics, drugs are administered to the whole organism by a route that is as convenient and safe as possible (usually by mouth), for days if not years. Consequently, the drug concentration in the vicinity of the receptors is usually unknown, and long-term effects involving alterations in receptor density or function, or the activation or modulation of homeostatic control mechanisms may be of overriding importance. The processes of absorption, distribution, metabolism and elimination (what the body does to the drug) determine the drug concentration–time relationships in plasma and at the recep-
tors. These processes comprise ‘pharmacokinetics’. There is considerable inter-individual variation due to both inherited