General Prescribing Guidance

• Prescribe only where necessary, and consider benefits vs risks.
• Involve the patient in decisions about their care, and respect patient autonomy.
• Ensure patient is aware of differences between adverse effects of drug and effects of disease, and any delays in beneficial effects.

• Many prescriptions are now computer-produced, but if you're hand-writing one, write legibly in indelible ink, date the prescription, and state the full name and address of the patient. All prescriptions should be signed by the prescriber. It is a legal requirement in the case of prescription-only medicines to state the age for children under 12 years, but it's good practice to do so in all cases.
• Avoid unnecessary use of decimal points (e.g.3mg, not 3.0mg). For quantities less than 1 gram, write in milligrams (e.g. 500mg, not 0.5g). For quantities less than 1 milligram, write in micrograms (e.g. 100 micrograms, not 0.1 mg.)
• Don't abbreviate micrograms or nanograms.
• Use millilitres, (ml or mL) not cubic centimeters or c.c.
• For prn dosage, state minimum dose interval.
• The 'number of days treatment' box can be used on NHS forms.
• Avoid abbreviations of drug names and preparations as these can be misinterpreted - e.g. Mist.Expect. Don't invent compound generic names, especially for sustained-release preparations.
• Write generics unless there are bioavailability issues, as this will enable the pharmacist to dispense any suitable preparation, avoiding expense and delay.
• Specify the strength and quantity. In the absence of this information the pharmacist will attempt to contact you. If unable to do so they can use their discretion and professional judgement to dispense up to five days' worth of treatment or appropriate amounts of combination packs or oral contraceptives. If they have insufficient information to make a judgement, they will return the prescription to you.
• If you want anything other than the name, strength, and dosage of the tablets to appear on the label, write it on the prescription in inverted commas - e.g. 'Sedative Tablets.'

Recommendations of the Joint GP Information Technology Committee of the BMA as follows:

• Minimum data requirements - date, patient's surname, one forename, other initials, address title and date of birth. The age of children under 12 years and of adults over 60 years must be printed in the box available; the age of children under 5 years should be printed in years and months.
• Doctor's name must be printed at the bottom of the prescription form,surgery address, telephone number, reference number, and primary care organisation. Prescriptions issued by GP registrars, assistants, locums, or deputising doctors should bear the name of responsible principal.
• The prescription must be printed in English without abbreviation, the dose must be in numbers, the frequency in words, and the quantity in numbers in brackets (e.g. 40 mg four times daily ).
• Supplementary warnings or advice should be written in full.
• Handwritten alterations should only be made in exceptional circumstances and any alterations must be countersigned in the doctor's own handwriting.
• Clearly mark duplicates as such.

• Drugs are rarely implicated in congenital malformations. However, this should not be a cause for complacency.
• Bear in mind effects of drugs on any woman of childbearing age or any man trying to father a child.²
• Drugs should be avoided if at all possible in the first trimester of pregnancy, unless the benefit to the mother outweighs the risk to the fetus.
• Use older drugs first-line as these will have a more detailed safety history; use the lowest effective dose.
• The period of greatest risk for teratogenesis is the third to the eleventh week of pregnancy.³
• Drugs given during the second and third trimesters may effect the growth of the fetus or functional development, or have a toxic effect on fetal tissue.³
• Drugs given shortly before term can have an adverse effect on labour or on the baby after delivery.²
• A full list of drugs known to be harmful and not know to be harmful is available in Appendix 4 of the British National Formulary, but no drug is safe beyond all doubt in early pregnancy. Further information is available from the National Teratology Information Service.³

• Sugar-free formulations should be prescribed wherever possible.⁴
• To improve concordance, Involve children and parents in the type of formulation - i.e. liquid or tablets.⁴
• If the dosage is under 5ml, the chemist will provide a syringe.²
• Many licensed medicines are used for unlicensed conditions in paediatrics, but 'off-licence' use is allowed under current legislation if it is in the interests of the patient.⁴ Guidance is now available from the BNF for Children.⁵

Palliative care may be defined as the total active care of patients whose disease does not respond to curative treatments.
• Palliative care requires a holistic approach and includes control of pain and other symptoms, as well as psychological, social and spiritual problems. Symptom and needs assessment requires a multidisciplinary team, including day hospice care, home care teams (often known as Macmillan teams), in-patient hospice care, and hospital teams.
• Include families in the care of the patient if the patient and the family wish it.
• Home treatment can be supported by community nursing services, social services, voluntary agencies and hospices as well as GPs. Assure the family that admission to hospital or hospice is available if the family cannot cope.
• Keep the number of drugs as few as possible. Oral medication should be sufficient unless there is severe nausea, vomiting, dysphagia, weakness, or coma, in which case consider parenteral medication.

• Avoid polypharmacy, excessive dosage, underdosage or inappropriate prescribing.
• Regularly review medication and stop medication if harm outweighs benefit.
• Consider non-drug measures - e.g. headache, insomnia may be helped by addressing social factors than by prescribing medication.
• A balance needs to be struck between preventing disease - e.g. such as anticoagulants or antiplatelet drugs for atrial fibrillation - and side effects from prophylactic drugs in patients with poor prognosis or poor overall health.
• Consider formulation. Encourage frail elderly patients to take tablets or capsules with enough fluid whilst in an upright position to avoid the possibility of oesophageal ulceration. Offer liquid preparations or dispersible tablets if available.
• Prescribing for age-related symptoms - e.g. age-related muscle weakness and difficulty in maintaining balance - are unlikely to be helped by drugs.
• Ask the patient or carers about self-medication.
• Opioid analgesics, benzodiazepines, antipsychotics, and antiparkinsonian drugs may all have unexpected effects on the ageing nervous system. Likewise use NSAIDs and antihypertensives with caution.
• Renal clearance is of paramount importance, and nephrotoxic drugs should be used with caution. Bear in mind also that intercurrent illness (e.g. lower respiratory tract infection) may reduce renal clearance and increase the risk of adverse effects for drugs with a narrow therapeutic window - e.g. digoxin.
• Adverse reactions may present in the elderly in unexpected ways - e.g. confusion (particularly hypnotics), constipation, (antimuscarinics and many tranquilisers) and postural hypotension and falls (diuretics and many psychotropics).
• Diuretics - overprescribed in old age. Do not use long-term basis for simple gravitational oedema which will usually respond to non-drug methods.
• NSAIDs - bleeding associated with aspirin and other NSAIDs more common in the elderly. Caution in patients with cardiac disease or renal impairment. For osteoarthritis, soft-tissue lesions and back pain, try non-drug methods, simple analgesia and/or low-dose NSAIDs.
• Common causes of adverse reactions - antiparkinsonian drugs, antihypertensives, psychotropics, and digoxin.

A recent change in the Misuse of Drugs Act came into force on 14th November 2005 which will enable prescriptions for all previously hand written controlled drugs to be printed. This change is gradually being rolled out to practices by computer suppliers. The legal requirements for content has not changed, and the computer will print out all the details, including total quantity in words and figures and the date. Phenobarbitone prescriptions, which previously required the date to be handwritten, are included in the change, so the date will be printed by the computer.

• About 50% of people do not take their medicines as intended. The trend is to move away from compliance to concordance (i.e. obtaining the patient's collaboration by involving them in decisions about prescribing, taking due account of their personal, cultural and religious beliefs). This is one of the cornerstones of the Medicines Management initiative, which is attempting to foster a closer partnership between the patients, clinicians and pharmacists concerning prescribing issues.
• It is good practice to have a system to check for prescriptions not collected or dispensed.
• Issues associated with poor compliance include lack of information about the purpose of a drug, how effective it is, the risk and severity of side effects, and how to take it.
• Other issues included complicated methods of administration, unpleasant taste, and physical problems such as swallowing difficulties and difficulties in opening the container.
• Discussing options will encourage the patient to seek alternatives rather than abandon the treatment altogether.
• Simplify drug regimes as much as possible (e.g o.d rather than b.d).
• Weigh up the benefits of combination preparations vs the problems of titrating individual drugs.

• Manufacturers' recommended doses are based on population studies and assumes 'one dose fits all'. However, there are genetic differences.¹¹
• New drugs are often marketed at the highest therapeutic level to demonstrate effectiveness in large numbers of patients, but companies are not required to provide data on lowest effective dose.
• Renal and hepatic function, age and adverse effects vs benefits should all be taken into account when considering dosage.²

GMC guidelines advise GPs to involve patients in decisions about their care and respect their beliefs. Even though a medicine is unlicensed and is lacking a body of evidence to support its use, it may be appropriate to prescribe it to meet a patient's needs. The legislation giving GPs the right to prescribe unlicensed medicines to patients after a face-to-face consultation is enshrined in paragraph 12.2 of the Medicines Act. This paragraph recently came up for review by the Government but has not been changed. The regulations governing the production of unlicensed medicines have however been tightened. GPs should be aware that if they prescribe unlicensed medicines they take full clinical responsibility for any adverse events that occur.

This is becoming an important issue, as evidenced by its increasing prominence in the undergraduate medical syllabus. Issues which need to be considered include:

• Evidence-based prescribing
• Interaction with other drugs
• Concordance, tolerability and formulation
• Adverse effects
• Checking dosages
• Using prescribing formularies