Tablets come in a great variety of shapes, sizes, colours and types. The formulation may be very simple (a plain white uncoated tablet) or complex (designed with specific therapeutic aims, e.g. sustained‐release preparations). Sugar coatings are used to improve appearance and palatability. In cases where the drug is a gastric irritant or is broken down by gastric acid, an enteric coating may be used; this is designed to allow the tablet to remain intact in the stomach and to pass unchanged into the small bowel, where the coating dissolves and the drug is released and absorbed.

Tablets may be formulated specifically to control the rate of release of the drug from the tablet as it passes through the GI tract. Terms such as ‘sustained release’, ‘controlled release’ and ‘modified release’ are used by manufacturers to describe these preparations. Care should be taken with these as different formulations of modified‐release preparations may not be bioequivalent (BNF [25]). These preparations may be prescribed by brand name to ensure the patient gets the same formulation each time (BNF [25]). Tablets may also be formulated specifically to dissolve or disperse readily in water before administration (‘soluble’ or ‘effervescent’). Other tablets are formulated to disperse in the mouth (‘oro‐dispersible’), while others must be chewed. The contents of these are swallowed by the patient after the contents have dispersed. Other tablets are designed to be placed and held under the tongue (‘sublingual’) or placed between the gum and inside of the mouth (‘buccal’). On release, the drug from these formulations is absorbed through the sublingual or buccal mucosa. Unscored or coated tablets should not be crushed or broken, nor should most modified‐release tablets, since this can affect the pharmacokinetic profile of the drug and may result in excessive peak plasma concentrations and side‐effects (Smyth [337]). Advice on whether modified‐release preparations can be split should be sought from a pharmacist.

Capsules offer a useful method of formulating drugs that are difficult to make into a tablet or that are particularly unpalatable. Capsules can also be easier for some patients to swallow.

Medicines are formulated in both hard and soft capsule shells. Capsule shells are usually made of gelatine and this may pose a problem for patients who are vegetarian or vegan, as well as some with religious beliefs with regard to products of animal origin. Capsule contents may be solid, liquid or of a paste‐like consistency. The contents do not cause deterioration of the shell. The shell, however, is dissolved by the digestive fluids and the contents are then released. Delayed‐release capsule formulations also exist. Gastro‐resistant capsules are delayed‐release capsules that are intended to resist the gastric fluid and to release their active substance or substances in the intestinal fluid (British Pharmacopoeia [31]).

If for any reason a capsule is unpalatable or the patient is unable to take it, the contents should not routinely be removed from the shell without first seeking advice from a pharmacist. Removing the contents from the capsule could destroy its properties and cause gastric irritation or premature release of the drug into an incompatible pH (Downie et al. [82]).

Lozenges and pastilles are solid, single‐dose preparations intended to be sucked to obtain a local or systemic effect to the mouth and/or throat (British Pharmacopoeia [31]).

Oral solutions are swallowed and the drug may exert a local effect on the GI tract or be absorbed into the blood to exert a systemic effect. Solutions can be relatively simple aqueous solutions but to be acceptable they must be palatable to patients and must be of an appropriate viscosity for pouring and palatability. Solutions can contain flavourings, colourings and sweeteners to improve taste; agents to increase viscosity; and preservatives. These are known as ‘excipients’. Some solutions are complex and may require the use of excipients to improve solubility (co‐solvents and surfactants) and/or stability (Aulton and Taylor [16]).

Patients may be allergic to excipients and details of excipients can be found in the summary of product characteristics for the medicine. These are readily available online at https://www.medicines.org.uk/emc.

A few medicines are formulated in non‐aqueous solutions and these may pose adherence challenges due to their palatability.

Suspensions are used where a drug is not water‐soluble but remains as solid particles dispersed throughout a liquid. A suspension will be formulated to ensure that the drug is optimally dispersed (Aulton and Taylor [16]) but this is challenging to achieve and most suspensions settle. It is essential, therefore, to thoroughly shake a suspension to disperse the drug before each use.

Mixtures are usually aqueous preparations, frequently containing more than one active ingredient. They can be in the form of either a solution or a suspension.

Syrups are formulations where the active ingredients are dissolved or suspended in an aqueous liquid containing a high proportion of dissolved sugar to form a syrup. The high sugar content acts as a preservative as well as making the medicine more palatable. The sugar content can contribute to dental caries (especially with long‐term medication), and patients should be advised on good dental hygiene (Roberts and Roberts [302]).

Due to long‐term stability problems in water, some liquid medicines are presented as powders or granules for reconstitution before use. The correct amount of water should be added and the medicine discarded after its expiry date. This will frequently be a relatively short period, typically 1–2 weeks.

These are viscous oral liquids that may contain one or more active ingredients; the solution usually contains a high proportion of sucrose. Linctuses are intended for use in the treatment or relief of coughs.

Traditionally elixirs are liquid medicines that contain alcohol as a cosolvent to dissolve the active ingredient. However, not all medicines that contain alcohol are designated as elixirs (Aulton and Taylor [16]).

Emulsions are formulations of two or more liquids that do not normally mix, with the drug usually dissolved in one of the liquids. They contain an emulsifier to produce either small water droplets in oil (water in oil emulsion) or small droplets of oil in water (oil in water emulsion). Like suspensions, oral emulsions must be shaken thoroughly to ensure even dispersion of the active ingredient. Although there some oral emulsions available, the majority of commercially available emulsions are currently for topical or injectable products (Aulton and Taylor [16]).

Medicine pots (Figure 15.6) allow a dosage form to be taken from its original container for immediate administration to a patient. The person who removes medication from its original container and places it into a medicine pot must oversee the administration of this medication. This responsibility cannot be transferred to someone else.

The practices of crushing, opening and splitting tablets should be avoided wherever possible due to a number of potential factors (RPS [311]):

If the practice is necessary, then commercially available tablet splitters (Figure 15.7) may increase the accuracy of tablet splitting (Verrue et al. [358]). Tablets that are unscored, unusually thick or oddly shaped, sugar coated, enteric coated or modified release are not suitable for splitting. Areas for consideration when using a tablet splitter include the following:

Tablet crushers (Figure 15.8) can be used when a patient has swallowing difficulties and no alternative dosage form exists. The crushing or splitting of dosage forms will be an unlicensed use of the medicine (unless this form of manipulation is covered by the product's marketing authorization). The Human Medicines Regulations ([133]) state that unlicensed medicines can only be authorized by a prescriber, so if tablets are going to be crushed, there should be discussion and agreement between the prescriber and the person who will administer the medicine. Discussion should also take place with a pharmacist to check that the tablet is suitable for crushing and that the efficacy of the medication will not be changed as a result. Tablets that are enteric coated, sustained release or chewable cannot be crushed. Areas for consideration when crushing a tablet include the following (RPS [311]):

When a tablet crusher is used, water should be added to the crushed tablet and the resulting solution drawn up using an oral syringe. The crusher should then be rinsed and the process repeated if necessary. Tablet crushers should be rinsed before and after use to prevent cross‐contamination with other medicines (Fair and Proctor [91], Smyth [337]). When a tablet crusher has been used, it should be opened and washed under running water, dried with a tissue and left to air dry on a tissue or paper towel.

Monitored dosage systems and compliance aids, for example dosette boxes (Figure 15.9), are designed to help patients remember when to take their medication. They can also let carers know whether patients have taken their medication. However, the default approach should be to dispense medicines in their standard packaging, on the assumption that patients can manage their medicines unless indicated otherwise. This is in line with NICE ([241]) guidance stating that monitored dosage systems should be considered as an option to improve adherence on a case‐by‐case basis, and only if there is a specific need to overcome practical problems. This should follow a discussion with the patient to explore possible reasons for nonadherence and the options available to improve adherence, if that is their wish. More recent guidance from NICE ([250]) on managing medicines for adults receiving social care reinforces this with the following recommendation:

NICE has also produced a quality and productivity case study (NICE [249]), which outlines actions intended to reduce the inappropriate use of monitored dosage systems by ensuring they are only issued on a case‐by‐case basis to address specific practical problems with medicines adherence. The inappropriate use of monitored dosage systems can make patients and carers less familiar with their medicines. The preparation and checking of unnecessary monitored dosage systems creates significant additional workload for hospital pharmacies, which can be reduced.

Therefore, monitored dosage systems should only be initiated in patients where there is a likely benefit and full assessment and consultation have been carried out. The RPS ([313]) reinforces these principles as well as providing guidance for pharmacists and their staff on filling and dispensing these devices.

The following should be considered when using these systems (RPS [313]):

The BNF for children (BNF [26]) recommends that an oral syringe should be used for accurate measurement and controlled administration of an oral liquid medicine to a child. For adults, the BNF ([25]) recommends that an oral syringe is supplied when oral liquid medicines are prescribed in doses other than multiples of 5 mL. The oral syringe should be marked in 0.5 mL divisions from 1 to 5 mL to measure doses of less than 5 mL (other sizes of oral syringe may also be available). It should be provided with an adaptor and an instruction leaflet. Otherwise, a 5 mL medicine spoon must be used for doses of 5 mL (or multiples thereof).

If a syringe is needed to measure and administer an oral dose, an oral syringe (Figure 15.10) that cannot be attached to intravenous catheters or ports should be used. These syringes are purple in colour. All oral syringes containing oral liquid medicines must usually be labelled by the person who prepared the syringe with the name and strength of the medicine, the time it was prepared and the patient's name. However, labelling is unnecessary if the preparation and administration is one uninterrupted process and the labelled syringe does not leave the hands of the person who prepared it. Only one unlabelled syringe should be handled at any one time (NHS England [230], NPSA [267]).