Medicines optimisation in patients with dysphagia

Good communication between healthcare specialities is recognised as a key component in the effective identification and management of patients with dysphagia⁸.

Whenever swallowing dysfunction is identified, a clinical evaluation should be undertaken to investigate and identify the cause and then treat appropriately. Furthermore, the prescriber also needs to evaluate how the patient’s medicines should now be administered in light of their condition. There are several strategies for consideration:

Alternative solid formulations

In milder cases of dysphagia the shape and size of the tablet may make a difference to the patient, with a capsule shaped medicine being easier for them to swallow.

The use of a tablet cutter may also provide an acceptable option, particularly when tablets are effectively scored and designed to help in the administration of part doses. However, research indicates that even with commercially available tablet cutters you cannot guarantee that the tablets will be cut to ensure accuracy of dose⁵².

Alternative routes of administration

Routinely, when patients are unable to swallow solid medicines, the prescriber reviews the patient’s regimen, omitting any medications that are unnecessary, and considers giving medicines by an alternative route eg. buccal, rectal or transdermal⁵³. A pharmacist and/or Medicines Information Centre will advise on whether alternative formulations of a particular medication are available.

Consideration should be given to both patient acceptability and any variation in the medicine’s absorption from alternative routes and hence the need for dose conversion.

Liquid formulations

Liquids are the preferred method of administering medications to patients with swallowing difficulties⁴⁷. Whilst many licensed liquid formulations are bioequivalent to the solid-dose version, in certain instances changing the formulation of a product may alter its bioavailability, efficacy and/or side-effect profile. It is important to check dose equivalence and adjust the dose frequency if necessary.

When prescribing dispersible tablets, the ingredients are not soluble in water. Rather they disperse as particles which may not be evenly distributed in water so part dosing is potentially inaccurate. Dispersible tablets may also require a larger volume of liquid which should be borne in mind when prescribing for patients with dysphagia.

Alternative medication

Where there is no suitable alternative formulation or alternative routes of administration then it may be necessary to select another licensed medicine with similar pharmacological effects, eg. transdermal glyceryl trinitrate patches instead of modified release isosorbide trinitrate³³ or liquid ACE inhibitor instead of bendroflumethiazide tablets.

Medication discontinuation

Occasionally it may be possible to stop the medication either temporarily if the dysphagia is believed to be transient, or permanently if the risks of the medication outweigh the benefits.

Unlicensed options

Some patients may have special clinical needs that cannot be met by the licensed medicinal options listed previously and that curtailing their treatment would have a detrimental effect on their condition. In this instance, the prescriber may have no option but to consider an unlicensed medicine: an unlicensed medicine being considered as either a ‘Special’, an import, a medicine used off-license, an extemporaneous preparation or an altered (crushed/opened) solid-dose formulation.

UK ‘guidance’ on the most appropriate use of unlicensed medicines for patients with swallowing difficulties is often inconsistent and lacks a strong evidence base. In particular, the decision whether to alter a solid-dose formulation (eg. dispersing tablets in water or opening capsules) as opposed to using a ‘Special’ can be a complex judgement and needs to balance the additional cost of ‘Specials’, expected patient outcomes and a multitude of risks – legal, clinical and professional. Selected guidance⁴⁷,⁷⁵ advocates the alteration of certain specific solid-dose forms in preference to the use of ‘Specials’ whilst elsewhere⁴⁶ altering a solid-dose formulation is recommended as a last resort.

In practice, considerations will vary depending on the respective patient, their medicine, and the professional competencies and infrastructure in place in a given situation. Most importantly, prescribers need to make informed case-by-case decisions in the knowledge of their professional responsibilities and the full implications of their decision-making.

Algorithm for the medication management of adults with swallowing difficulties ⁴⁶

Administering medications via enteral feeding tubes

Most products are not licensed for administration via enteral feeding tubes and in these circumstances the prescriber and practitioner accept any liability for any adverse effects resulting from the administration of that drug. However, a small but growing number of oral solutions from Rosemont Pharmaceuticals – furosemide, ramipril, metoclopramide hydrochloride and clonazepam (as of June 2016) – are now approved for administration via NG and PEG tubes.

Whilst using a feeding tube to administer a drug should be considered a last resort – largely due to the significant risk of blockage – the use of enteral feeding tubes as a route of drug administration is becoming increasingly common. The British Association for Parenteral and Enteral Nutrition (BAPEN) provide a practical guide for administering drugs via enteral feeding tubes⁵⁵.

In general, the medication needs of patients should be reviewed if they are switched to enteral feeding, as certain medications may no longer be required.

Liquids or soluble tablets are the preferred formulations to be administered via a feeding tube (some injections can be given enterally). Where possible, a non-viscous and non-granular liquid should be used. Crushing tablets or opening capsules should be considered as a last resort, particularly due to the risk of inaccurate dosing⁵⁶ and tube blockage.

Tube blockage can deprive a patient of nutrients, fluids and medication. Most commonly, blockage is due to inadequate flushing⁵⁷.

Blockage may necessitate replacement of the feeding tube potentially subjecting the patient to an invasive procedure, although adequate flushing should prevent this. If blockage occurs, practitioners are advised to try aspiration to remove curds/particulate matter from the tube. This should be followed by an attempt to flush the tube with warm water.

Tube blockage (and impaired drug efficacy) may also be caused by drug interactions with the enteral feed. As a general rule if the absorption of a drug is affected by food or antacids, it is also likely to be affected by enteral feed. Where possible, practitioners are advised give medication during a break in the feeding regimen to minimise the risk of interaction. Certain medications are known to be particularly problematic in terms of their interactions with enteral tubes (eg. PPIs, phenytoin, quinolones, tetracyclines, rifampicin). Practitioners are encouraged to seek the advice of a pharmacist when reviewing a patient’s medication.

Religious, cultural, and personal beliefs

As always, the prescriber should be sensitive to religious, cultural, and personal beliefs that can affect a patient's acceptance of medicines. Cultural sensitivities may be a particularly important consideration when assessing alternative routes of administration for a patient with dysphagia. Furthermore, some religions prohibit the ingestion of certain foods and drinks, for example, any medicines which contain porcine derivatives, alcohol or non-Halal excipients or ingredients, may pose a problem to Muslim patients. This may be particularly important when considering an alternative liquid formulation and prescribers are advised to check a manufacturer’s Summary of Product Characteristics and/or check a medicine’s ingredients directly with the manufacturer.

Whilst some manufacturers claim the use “Halal gelatin” in their manufacturing processes, Rosemont Pharmaceuticals is the first UK pharmaceutical company to be granted Halal approval by the Halal Food Authority for its manufacturing facilities. It has also received Halal certification for many of its licensed liquid medicines.