Medicines Information

Enquiry answering guidelines

These guidelines draw together current UKMi guidance and resources (e.g. quick question guide, workbook, specialist centres, Medicines Q&As) and provide a guide to answering enquiries categorised by type. They can be easily adapted to include local resources.

The document can be used for training or as a helpful reminder for more experienced medicines information staff looking for inspiration.

For all enquiries you need to know:

The enquirer.
Contact details.
Urgency of enquiry.
Purpose of enquiry e.g. patient specific, project.
What sources already been used (NB. Try to assess enquirers experience of searching more complicated resources as you may feel you need to do extra research).

Each monograph is divided into the following sections:

Background information specific to the enquiry type.
Resources.
First-line resources.
In-house past enquiries. Always be aware of currency of information.
UKMi Medicines Q&As – its like past enquiries - you will be annoyed if you a find a relevant one later!
Other easily accessible resources.
Additional resources.
Local resources e.g. contact details of experts, relevant departments, policies, in-house filing systems.
Answering the enquiry – useful pointers to factors that should be considered.
Keyword suggestions for future enquiry retrieval.

Key to resources: F = free access to NHS, P = purchase or subscription required. Where there is an electronic version this has been listed as the preferred choice.

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Adverse Drug Reactions

Breast Feeding

Compatibility Of Intravenous Drugs

Compatibility Of Subcutaneous Drugs

Complementary Medicine

Contraception (hormonal)

Dental

HepaticImpairment

Identification

Immunisation

Interactions

New Products

Paediatrics

Palliative Care

Poisoning or Overdose

Pregnancy

Psychiatry

Renal Impairment

Sport

Substance Misuse

Travel Medicine

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Publication date: Jan 07, Revision date: Jan 09

Adverse Drug Reactions

Background information

Retrospective enquiries (i.e. suspected ADR has already occurred)

Establish patient details, including age, sex etc.
What is the indication for the drug and any relevant medical history (e.g. renal function)?
What is the current and previous medical history if relevant, including risk factors for the ADR?
Is there a history of adverse drug reactions or allergies?
List current drug therapy, including OTC, alternative therapies and drugs of abuse whenever possible, plus any medication taken within the last 3 months.
What is the timing of the reaction in relation to start or dose increase of the suspected drug?
Obtain a full description of the signs and symptoms of the reaction, clarify reactions such as 'rash', 'abnormal LFTs', 'aching all over'.
Has the suspected drug been stopped?
How has the patient been managed so far?
Has rechallenge, deliberate or inadvertent, been undertaken?
Did the suspected ADR resolve when the suspect drug was stopped?
What are the results of any relevant biochemical tests e.g. renal function tests, liver function tests, full blood count, biopsies, relevant ultrasound or screening tests.
Does the enquirer want to know which drug, A or B, is more likely to have caused side effect X?
Is the enquirer involved in a legal case? Always be aware that this may be the scenario (often enquirers do not mention this).
Has the manufacturer been informed or a yellow card completed?

Prospective enquiries

Does the enquirer think that the patient may be at particular risk of an ADR e.g. a patient with a history of an ADR to the same class of drugs? If so, what were the signs and symptoms of the suspected previous reaction? N.B. caution may be required when using other drugs with similar ADR profiles.
Does the enquirer just want some general information e.g. for informing a patient of possible side effects?
Does the enquirer want to know more information about a specific side effect e.g. because patient has asked?
Does the enquirer want to assess the risk/benefit comparison between two drugs e.g. which is safer, drug A or drug B (often in relation to a specific side-effect)?
Some enquiries will involve a mixture of the two e.g. if a patient has a reaction which is subsequently thought to be an ADR then it could be anticipated that the enquirer will want suggestions for alternatives.

Resources

Source / Notes
First-line resources
In-house past enquiries. / F
Relevant Medicines Q&Asvia / F
Electronic Medicines Compendium / F / For new drugs, adverse reaction information in the SPC comes from clinical trials, data are limited and uncommon idiosyncratic reactions are unlikely to be included. The SPCs for more established drugs include adverse reactions identified by postmarketing surveillance studies and spontaneous reporting schemes.
BNF / F / Clinically relevant adverse effects are listed, generally in order of frequency and arranged broadly by body systems.
AHFS Drug Information via / P / Monographs often contain extensive information on ADRs.
Martindale via / P
Meyler's Side Effects of Drugs, Dukes and Aronson. / P / Presented as individual drug monographs in alphabetical order with general class monographs complemented by specific drug monographs. Also contains information on non-drugs e.g. toxins, catheters.
Additional resources (tailor to local use/availability)
Adverse Drug Reactions, Lee A. / P / Describes ADRs by organ class, lists commonly implicated drugs and gives tips on management of suspected ADRs.
Davies's Textbook of Adverse Drug Reactions, Davies et al. / P / Chapters are arranged by system and adverse effect. NB. Now relatively out of date (1998).
CHM Drug Analysis Prints (DAP) via MHRA
CSM Drug Analysis Prints / F / Complete listings of the suspected ADRs reported to the MHRA through the Yellow Card Scheme by healthcare professionals and patients are provided in Drug Analysis Prints (DAPs). When sending DAP data to an enquirer it is important to enclose a sheet explaining how to interpret this (download from the MHRA website).
Micromedex / P / Drugdex Drug Evaluations - Reports are normally referenced.
Reactions weekly / P / Paper journal or via Adisonline.
Bibliographic databases e.g. Medline, Embase, Pharmline / F/P / Suggested terms: the reaction with the subheading ‘chemically induced’ (Medline) or ‘side effect’ (Embase) and/or the drug name with the subheading ‘adverse effects’ (Medline) or ‘adverse drug reaction’ (Embase).
Current Problems in Pharmacovigilance via MHRA website at Current Problems / F / Current awareness bulletin.
Manufacturers’ Medical Information departments. / F / Companies are legally obliged to follow up telephone enquiries about ADRS (by sending an adverse event reporting form).
Local resources

Answering the enquiry

For retrospective enquiries use the information you have obtained from the 'background information' questions and try to assess causality using the following criteria:
The nature of the reaction - certain disorders are commonly drug-induced e.g rashes, constipation, gastrointestinal haemorrhage.
Previous SPC or literature reports describing the reaction.
The timing of the reaction can vary but most ADRs appear shortly after a drug is started or the dose is increased.
Outcome on drug withdrawal, if resolution occurs this is a positive dechallenge.
Rechallenge outcome, although positive rechallenge strongly suggests drug cause deliberate rechallenge is rarely justifiable and should not be suggested.
Risk factors, some patients have an increased susceptibility to ADRs (e.g. children, elderly, multiple disease states, atopic patients).
Laboratory and diagnostic tests should indicate if there is a non-drug cause, ADRs are often a diagnosis of exclusion.
When interpreting ADR data for the enquirer, be clear about the limitations of the Yellow Card data. Warn that although there may be X number of reports we do not know the Y number of people who have received the drug, therefore you cannot extrapolate ADR incidence.
If there is a strong suspicion that an ADR has been identified encourage completion of a Yellow Card.

Keywords: The drug name, disease term for the adverse effect.

Drugs in breast feeding

Background information

Identify drug, indication, dose, frequency, route of administration and duration of treatment.
Has the baby already been exposed to the drug in pregnancy or by breastfeeding? If so, have any problems been identified?
How old is the infant, and is he/she premature or full-term?
Is the baby well? Is there anything to suggest that the infant may be at increased risk of drug harm – such as impaired kidney or liver function?
What would happen if the drug is stopped, or not used?
Has any alternative been considered or tried?

Resources

Source / Notes
First-line resources
In-house past enquiries. / F
Relevant Medicines Q&Asvia / F
BNF for Children BNFC.org / F / Notes on breast feeding in each monograph under ‘Cautions’.
Electronic Medicines Compendium / F / SPCs have variable content and often make statements based on legal concerns rather than evidence. However, manufacturer’s medical information departments can be helpful.
Therapeutics in Pregnancy & Lactation. Lee A et al. / P / Useful for management of common conditions in pregnancy and suggestions for suitable choices.
Drugs in Pregnancy and Lactation. Briggs GG et al. / P / Very detailed monographs. Use for enquiries that require in-depth research on individual drugs. Little practical advice.
UKMi Drugs in Lactation / P / General guidance on drug administration during in breast feeding and a quick reference guide giving advice on individual drugs. There are monographs on a number of therapeutic groups.
Additional resources (tailor to local use/availability)
Medications and Mothers’ Milk. Hale, T. / P / A handy quick reference guide with easy to access information.
Drugs during Pregnancy and Lactation. Schaefer et al. / P / Has less detail on drugs in breast feeding than other resources.
Micromedex / P / Use for drugs with very little UK information.
UKMi Drugs in Lactation specialist centres. / F / W Midlands (0121) 311 1974 or Trent (0116) 255 5779 provide a support directly to local MI centres for complex enquiries, for interpretation of evidence and for advice in high risk situations (e.g. prematurity). Contact one of these centres ensuring you have full background details.
Neonatal Formulary (Northern Neonatal Network) Hall & Richmond. / P
Toxbase / F / Limited information on drugs in lactation (look under Poisoning in Pregnancy section).
The AmericanAcademy of Pediatrics / F / Transfer of Drugs and Other Chemicals into Human Milk - tables and general guidance dated September 2001. Contains information that may not be found elsewhere e.g. food and environmental agents, radioactive compounds, effects of smoking, etc.
Prescribing Update, Ministry of Health, New Zealand / F / Gives a safety assessment of commonly used drugs (e.g. analgesics, antibiotics) and tabulates information on milk/plasma ratios and the % of maternal dose delivered via breast milk for individual drugs. Last updated May 2001.
Bibliographic databases e.g. Medline, Embase, Pharmline / F/P / Suggested terms: MILK-HUMAN, BREAST FEEDING, INFANT, NEWBORN, BREAST MILK
Local resources

Answering the enquiry

The following principles should be followed when prescribing for breastfeeding mothers:

Avoid unnecessary drug use and limit use of over-the-counter (OTC) products.
Assess the benefit/risk ratio for both mother and infant. If the drug is not essential it should be avoided or a non-drug approach used. There may be alternative drugs that are safer to use.
Avoid use of drugs known to cause serious toxicity in adults or children.
Drugs licensed for use in infants do not generally pose a hazard when used in a breast feeding mother.
Neonates (and particularly premature infants) are at greater risk from exposure to drugs via breast milk, because of immature excretory functions and consequent risk of drug accumulation.
Choose a regimen and route of administration that presents the minimum amount of drug to the infant. If the drug can be given once daily at bedtime, this may reduce neonatal exposure if less breast-feeding occurs overnight. Breast-feeding immediately before a dose will avoid exposure to peak plasma levels.
For a very short course of treatment (less than 48 hours) breast-feeding could be interrupted temporarily, but longer interruption can make resumption difficult. Not all mothers can cope with bottle-feeding, in which case breast-feeding with limited infant exposure to a drug may be the least worst option.
It is best to avoid long-acting preparations, especially those of drugs likely to cause serious side effects (e.g. antipsychotic agents), as it is difficult to time feeds to avoid significant amounts of drug in breast milk.
Multiple drug regimens may pose an increased risk especially when adverse effects such as drowsiness are additive.
Infants exposed to drugs via breast milk should be monitored for unusual signs or symptoms.
Avoid new drugs if a therapeutically equivalent alternative that has been more widely used is available. A robust assessment of the balance of benefit to risk requires data both on the drug's passage into breast milk and its effects in infants: there is rarely enough information available for new drugs to allow such an assessment to be made. If a drug with limited data is deemed to be clinically necessary or for any further information, contact the UKMi Drugs in Lactation specialist centres for advice.

Keywords: BREAST FEEDING, drug name and disease name (if appropriate)

Compatibility of intravenous drugs

Background information

How many intravenous lines are available, what type of lines are they (central or peripheral), how many lumens does each line have. Can other lines be inserted if necessary?
What is the patient receiving through the lines at the moment? Ask about blood products, TPN etc as well as drugs. For current drugs:
Check dose and administration schedule- are they being given continuously, or by short infusion or as a bolus? If continuous infusion, can they be given intermittently?
What diluents and concentrations are being used?
Can any drugs be discontinued?
Which drugs are to be added and why?
How will the drugs be mixed e.g. in the same bag, the same intravenous line (Y site), same syringe or the same venflon?
Is there a choice of drugs that could be used?
Are there any limitations on choice e.g. fluid and electrolyte restrictions, renal or hepatic dysfunction?
Can the patient tolerate administration by another route e.g. nasogastric tube, oral, rectal, intramuscular, subcutaneous, topical?

N.B. If the enquiry concerns the compatibility of drugs in a syringe driver for subcutaneous administration please refer to the ‘Compatibility of subcutaneous drugs’ monograph.

Resources

Source / Notes
First-line resources
In-house past enquiries. / F
Relevant Medicines Q&Asvia / F
BNF / F / Contains information about compatible/incompatible diluents.
Electronic Medicines Compendium / F / SPCs may contain information about compatibility of commonly used admixtures.
Handbook on Injectable Drugs. Lawrence A Trissel. / P / N.B. This is a US textbook, but there are UK drug monographs in a section at the back.
Additional resources (tailor to local use/availability)
Pharmaceutical manufacturer. / F / They may have unpublished data, although many generics manufacturers have little or no information.
Micromedex / P / Contains information about compatibility of intravenous admixtures if known.
The Hammersmith IV Guide / F* / *Only free to contributing Trusts, all Trusts in Wales & N.Ireland. Paper version also available.
UCL Hospitals Injectable Drug Administration Guide. / P
AHFS Drug Information via / P / Information in the stability section of individual monographs.
Bibliographic databases e.g. Medline, Embase, Pharmline / F/P / Suggested terms: ADMINISTRATION-INTRAVENOUS and DRUG INCOMPATIBILITIES
Local resources

Answering the enquiry

When checking compatibilities consider alternative ways of solving the problem e.g. by using other routes of drug administration. You must consider the problems associated with other routes and whether they would be appropriate for that particular patient.

When answering this type of enquiry consider:

Are all the drugs essential?
What are the possible mechanisms of interactions – chemistry i.e. pH, adsorption?
Is it possible to administer drugs by an alternative route?
Could another line be inserted?
Is there more than one option available, i.e. could a different drug be used to avoid a compatibility problem?
Could the timing of administration be altered to avoid the need for mixing?

Keywords: drug names, ADMINISTRATION-INTRAVENOUS, DRUG INCOMPATIBILITIES

Compatibility of subcutaneous drugs

Background information

What other medication is the patient receiving and by what routes?
Which drugs need to be mixed and at what dose?
What is the diluent to be used and the concentration required or the preferred total volume?
Over what time period is the infusion to be given?
What other routes of administration are available e.g. i.v. lines?
Establish how the patient is fed – an enteral feed tube offers a potential alternative administration route.

N.B. If the enquiry concerns the compatibility of drugs for intravenous administration please refer to the ‘Compatibility of intravenous drugs’ monograph. See also ‘Palliative Care’ monograph.

Resources

Source / Notes
First-line resources
In-house past enquiries. / F
Relevant Medicines Q&Asvia / F
BNF / F / Section on prescribing in palliative care includes information about drug administration via syringe drivers.
The Syringe Driver, Dickman, Scheider and Varga / P / Contains comprehensive information about two or more admixtures of commonly used combinations.
Palliative Care Formulary (PCF2). Twycross et al. / F / Once registered, click on ‘Enter formulary’ then ‘syringe driver’.
Handbook on Injectable Drugs. Trissel LA. / P / N.B. This is a US textbook, but there are UK drug monographs in a section at the back.
Additional resources (tailor to local use/availability)
Electronic Medicines Compendium / F / However, very few injectable drugs are licensed for subcutaneous injection or infusion.
Palliative Medicine Handbook. Ian Back. / F
/ F / Website run by Dr Ian Back. Click on ‘syringe drivers’ to enter drug compatability database.
A Guide to Symptom Relief in Palliative Care. Regnard and Hockley. / P
Bibliographic databases e.g. Medline, Embase, Pharmline / F/P / Suggested terms: SUBCUTANEOUS-DRUG-ADMINISTRATION, INJECTIONS-SUBCUTANEOUS, ADMINISTRATION-SUBCUTANEOUS
Local resources

Answering the enquiry

For enquiries originating from primary care there is a Macmillan nurse attached to every PCT. For enquiries about the management of a specific patient (other than straightforward medicines information queries), advise the enquirer to contact this nurse.
Some drugs are too irritant to be given by the subcutaneous route, e.g. prochlorperazine, diazepam and chlorpromazine.
Some drugs should never be mixed e.g. phenobarbitone. Many palliative care units will always give dexamethasone in a separate syringe driver.
Use of more than one syringe driver may be an option if there are compatibility problems and alternative routes are unsuitable.
Use of a larger total volume will improve the stability of many drug combinations and may be an option for some patients.

Keywords: Drug names, ADMINISTRATION-SUBCUTANEOUS, DRUG INCOMPATIBILITIES