Assessing Medicines on Admission in Acute Patients

Introduction

The medications reconciliation process is an integral part of the patient’s journey when admitted to hospital. Intentional decisions should be made by the prescriber at this point about whether to continue, withhold, amend, or stop a medication based on the clinical picture of the patient (see  Good Prescribing Practice for Inpatients - Medicines Reconciliation, HEPMA and IDLs and the NHSGGC Medicines Reconciliation Policy in section 6.5, for more detail). It is important to note that specialist medicines are often not accurate and / or included in a patient's Emergency Care Summary (ECS) or GP printout (e.g. clozapine, darbepoetin, methotrexate, antipsychotic depot injections, biologics, systemic anti-cancer treatments (SACT), antiretrovirals for treatment or prevention of HIV), therefore, more than one source should always be used to verify the medication history.

Below are general principles to consider and illustrative examples of issues for a select group of medications.

Examples of situations using selected medicines

Considering the principles above, it should be taken into account that each individual patient and their circumstances will differ. In view of this, the generalised advice for selected medicines or groups of medicines below needs to be considered alongside the patient's individual circumstances.

The following examples are not an exhaustive list of medicines where such considerations are required, but simply to illustrate the principles outlined above.

Antiplatelets and anticoagulants:

In most cases, you would not consider prescribing both an antiplatelet and an oral anticoagulant for a patient - unless on the advice of a specialist - as this combination is associated with a significantly higher major haemorrhage complication rate than either agent alone. If a patient is admitted on warfarin, ensure the dose is clarified with a reliable source e.g. an anticoagulation dosing letter (available via Clinical Portal for patients attending GCAS) or the patient themselves. When starting any new medicines, check for interactions with anticoagulants (particularly warfarin), as well as remembering to consider other medicines which might increase the risk of bleeding. Rarely is it appropriate to prescribe a low molecular weight heparin (LMWH) for thromboprophylaxis in patients receiving therapeutic anticoagulation.

Benzodiazepines and opiate substitute treatment (OST):

Benzodiazepine treatment and OST (such as methadone and buprenorphine) should be confirmed on each admission by contacting the patient’s community pharmacy. Information gathered should include the dose, last supervised dose, and current prescriptions running in community. Regular prescriptions of benzodiazepines or OST should not be discontinued without advice from the Acute Addiction Liaison Service unless clinically indicated. For other important issues to consider before prescribing, see the Acute management of people who use Drugs guideline.

Clozapine:

Clozapine is a time-critical medication; if more than 48 hours have elapsed since the last dose then re-titration is necessary. It is prescribed and dispensed within the specialist mental health service and may not always appear on the patient's Emergency Care Summary (ECS). For advice on supply, contact details for the specialist mental health service, and general points to consider in the management of patients on clozapine admitted to an acute hospital, see guidance here.

Diabetes:

Always carefully check the type of insulin, dose and frequency of administration, particularly when importing from ECS to Clinical Portal. ECS / Clinical Portal are not likely to contain dose information and therefore confirming insulin dose and frequency with another source (e.g. patient or carer) is essential. Be aware of concentrated insulin pens (e.g. Toujeo 300 units/ml, Tresiba 200 units/ml, Humalog 200 units/ml) and combination pens (e.g. Xultophy (insulin degludec 100 units/ml and liraglutide)). If patients on insulin pumps are admitted and unable to self-manage, remove the pump and commence Variable Rate Intravenous Insulin Infusion (VRIII). Always continue basal / long-acting insulin in a type 1 patient (even if fasting or nil-by-mouth), however, the dose may need adjustment. In patients with type 2 diabetes, non-insulin therapies may need to be withheld or the dose adjusted. See the GGC Guideline Diabetes Inpatient Prescribing - Frequently Asked Questions for further information and advice.

Drug interactions:

Check for any drug interactions between the patient’s existing drug therapies, including over the counter (OTC) medications and herbal remedies. This should also be carried out when prescribing new medicines. Some medications interact with food (including enteral feeds), tobacco smoke, and alcohol. Check the BNF or Stockley’s (Log in via OpenAthens to access) for common interactions. For general antibiotic interactions, see Antibiotic Allergy and Interactions. For information on QT interval prolongation, see below. University of Liverpool interaction checkers are also available to check interactions between medications and COVID, HIV or hepatitis treatments. Contact your clinical pharmacist or Medicines Advice team (see Appendix 6 for contact details) if you are unsure how to manage an interaction or its potential significance.

Frailty and polypharmacy:

Patients with multiple morbidities or frailty are at risk of harmful polypharmacy and increased susceptibility to adverse drug reactions. Review culprit medications and deprescribe where clinically indicated. See Polypharmacy Review in Adults Living with Moderate to Severe Frailty (poster) and Polypharmacy: Manage Medicines for further resources and guidance.

HIV / Hepatitis C medication:

Missed doses of HIV / Hepatitis C (HCV) treatment can adversely affect treatment outcomes and risk development of resistance. Contact the HIV pharmacy team or the HCV pharmacy team who can confirm treatment regimen as well as provide drug interaction advice, if needed. Guidance regarding potential drug interactions can be found here. See HIV infection in hospital for further information.

Immunosuppressant and chemotherapy agents:

Anticancer medicines, including chemotherapy and biological modifiers, should be withheld in all circumstances until advice is sought from the on-call haematology or oncology consultant. For further information see SOP9: Patients on oral SACT admitted to Non-Cancer Wards (link is only active if accessing via NHS network). Specific SACT protocols can be viewed on the WoSCAN intranet site (link is only active if accessing via NHS network). Common toxicity from SACT includes: myelosuppression, vomiting, diarrhoea, and mucositis, though side effects are numerous and drug-specific. Patients who are receiving, or who have previously received, immune checkpoint inhibitors (e.g. ipilimumab, pembrolizumab, nivolumab, avelumab, atezolizumab, cemiplimab, durvalumab) are at risk of immune-related adverse events. See Immune-related adverse events or WoSCAN specific guidelines (link is only active if accessing via NHS network) for more information.

Contact the appropriate clinical team regarding patients on Disease-Modifying Antirheumatic Drugs (DMARDs) or biologics before deciding whether to withhold immunosuppressants, unless infection is suspected, in which case withhold and discuss with the specialists. If the patient is on long-term corticosteroids, see below for further advice.

For transplant patients, discuss with the relevant transplant team before deciding whether to withhold immunosuppressants.

Long-term corticosteroids:

In the presence of severe intercurrent illness (e.g. infection), to prevent adrenal insufficiency consider doubling the steroid dose or giving intravenous hydrocortisone. This should also be considered for patients undergoing surgical procedures. See Management of Adrenal Insufficiency for further advice. In certain circumstances, for example in severe / life-threatening gastrointestinal bleeding, it may be appropriate to consider temporarily withholding glucocorticoid therapy. Seek senior medical advice.

Myasthenia Gravis:

Medications to control the symptoms of myasthenia gravis (MG), including pyridostigmine or steroids, should not be withheld for any significant length of time (i.e. >2 hours) as there is a risk of myasthenic crisis. Pyridostigmine should be administered at the same times the patient takes it at home and missed doses should be avoided. For advice on pyridostigmine supply and the management of patients with MG admitted to acute hospitals - including the prescribing of new medications, if infection is present, or if the patient is nil-by-mouth - see guidance here.

Nephrotoxic drugs:

In patients with acute kidney injury (AKI), review whether to withhold medications which may exacerbate renal impairment such as non-steroidal anti-inflammatory drugs (NSAIDs), angiotensin-converting enzyme inhibitors (ACEi), angiotensin receptor blockers (ARBs), and diuretics. Decision-making should be carried out on an individual basis, bearing in mind that it may be appropriate to continue certain medications depending on the clinical picture. If medication is withheld, review renal function regularly and consider restarting these drugs once renal function improves. Depending on the patient’s clinical situation, permanent discontinuation or dose adjustment may be necessary.

Additionally, review all other prescribed medicines to assess whether dose adjustments are needed according to the degree of renal impairment. Before prescribing any new medication, consider whether it may exacerbate AKI and/or whether dosage adjustment may be required. This is particularly important for certain antibiotics and opioid analgesics. If there is any uncertainty, seek senior advice promptly.

Prescribing guidance:

• eGFR and Cockcroft-Gault estimates are unreliable during AKI due to delayed creatinine changes, which could lead to potential dosing error.
• Do not use eGFR or Cockcroft-Gault estimates alone for dose adjustment during evolving AKI. Also consider serum creatinine trends, urine output and use clinical judgement when deciding dosing.
• Seek specialist advice from renal or pharmacy teams for high-risk medications.

Nil-by-mouth or swallowing difficulties:

Follow the general principles outlined above, clinically review the patient’s medications and ensure essential ones are continued via a safe administration route and in a suitable formulation. Dose adjustment may be necessary when switching to an alternative route or formulation. For information about the general principles of drug administration via enteral feeding tubes, refer to the GGC Medicines Update Blog Administration of Medicines via Enteral Feeding Tubes in Adult Patients. For drug-specific administration advice, access Drug Administration via Enteral Feeding Tubes online book for individual monographs (access via Medicines Complete). Information regarding administration in dysphagia and covert medication can be found here. For patients living with Parkinson’s disease, please see Parkinson’s Disease in Acute Care for more information. If there is any uncertainty, contact your clinical pharmacist / Medicines Advice team for more guidance (see Appendix 6 for contact details). 

Parkinson's disease medications:

Medications used in the treatment of Parkinson’s disease (PD) are time-critical. An accurate history of the medications, dose, timings, and preparations should be taken. Dose timings should be clearly annotated on HEPMA or the patient’s prescription chart. Missed or delayed doses can have serious adverse effects and must be avoided. PD medications should be administered on time, every time. On time means within 30 minutes of the patient’s prescribed time and they should not be stopped for any significant length of time i.e. >2 hours. The PD nurse specialist should be informed of all PD patient admissions. See Parkinson's Disease in Acute Care for general information on the management of patients living with PD (including management of nil-by-mouth patients), how to obtain a supply out of hours, and useful contact details.

QT interval prolonging medicines:

Be aware that a large number of drugs (and combination of drugs) can prolong the QT interval. Some drugs can have a dose-dependent effect, for example citalopram. Further information on drugs and QT interval prolongation can be found in a Medicines Update blog series on QTc prolongation (April 2024) at www.ggcmedicines.org.uk. Information can also be found on www.crediblemeds.org (free registration required for access).

Sick Day Rules:

Acute illness with risk of dehydration (e.g. vomiting, diarrhoea and fever) can increase the likelihood of adverse effects from certain medications. Advise patients to temporarily stop these medicines at times where there is a risk of significant dehydration. Restart once eating and drinking normally and recovery is established (usually after 24-48 hours of symptom resolution). Provide clear patient instructions in advance and consider written Sick Day Rules guidance.

Table 1 – Medications which should be temporarily withheld during risk of dehydration

* Consider checking ketones and refer to Diabetes Inpatient Prescribing - Frequently Asked Questions

This list is not exhaustive and there are other medicines you may wish to consider withholding or adjusting during periods of acute illness, depending on the patient's condition.

Table 2 – Medications to consider withholding or adjusting in acute illness

* Note it might not always be obvious that a patient is taking these medicines as they may not be on their medical records.

Guideline reviewed: May 2026

Page last updated: July 2026