Problems with medication adherence may involve taking a higher or lower dose than prescribed, taking medicine at the wrong time, just forgetting or making a conscious decision not to follow the prescribed treatment. Although often useful, dose administration aids are not a panacea for all such problems.
In discussing possible use of a dose administration aid with a patient, important issues to be considered include:
- the suitability of the medications for repackaging
- the logistics involved in filling and collecting the pack
- cost to the patient and/or the health service
- the additional risk of human error
- the most suitable type of device
- how inhaled, as required, or liquid preparations are to be managed.
There are a number of preparations that should not be removed from the manufacturer's package and therefore they are unsuitable for use in a dose administration aid. Examples include wafer and sublingual preparations (such as olanzapine wafers), dispersible preparations (such as soluble aspirin), drugs that degrade when exposed to light (such as nifedipine) and hygroscopic preparations (such as sodium valproate tablets).
Warfarin therapy often presents a conundrum for prescribers. Although adherence is critical, a fixed dose is often not possible so orders for dose administration aids may need alteration. Frequent changes to a dose administration aid may be difficult to manage, particularly if the preparation of the aid is outsourced to a pharmacy which may be hundreds of kilometres away. Prescribers need to ensure strategies are in place for patients to manage such scenarios.
Beware the practical problems not anticipated by professionals. Complaints from the Kimberley region include the aid not fitting into a handbag (commonly one of the only relatively secure places for medicines storage), insomnia from crinkling blister-packs under the pillow at night and the backing card disintegrating and disgorging soggy medicines after sitting in a bag with a moist plug of 'ngunju' (chewing tobacco).
The Tiwi Islands provide an example of where on-site preparation of dose administration aids and the availability of a pharmacist to provide drug counselling (with the support of local pharmacy assistants) allowed more timely access to medicines. This resulted in a documented increase in the collection rates of dose administration aids.4