Patient compliance, barriers

These testosterone systems illustrate two different approaches to solve the problem of inadequate percutaneous absorption rate. In the former case, the patch must be applied to the body s most permeable skin site, the scrotum (which has been shown to be at least five times more permeable than ary other site). In the latter, the difficulty is resolved by creating a transdermal formulation which includes excipients to reduce barrier function. Neither solution is ideal scrotal application is clearly not preferred from a patient compliance standpoint on the other hand, permeation enhancers, by their very nature, tend to be irritating (and the more effective they are, the greater the irritation they provoke). This general problem, which presently limits the application of transdermal delivery, is now discussed in more detail. 

At best, chronic injection is an unpleasant prospect with a host of hygiene issues and potential side effects. At worst, it can create a barrier to patient compliance with the particular drug regimen required to most effectively treat a given disease, since some patients choose irregular treatment or no treatment at all when faced with frequent injections. 

Transdermal drug delivery (TDD) is known to offer many advantages over the oral and injectable routes for systemic drug delivery. However, the skin is a complex and dynamic organ with marked barrier function, which results in limitations and variations in the amount and nature of drugs that can be delivered across the skin and into the bloodstream. Thus a continual search for ways to optimize the permeation of drugs across the skin exists, in an attempt to enhance delivery and improve patient compliance. 

Side-effects or the concern about side-effects listed in patient information leaflets can also be a barrier to patient compliance. What patients perceive is the probability of a side-effect listed and what the terminology used actually means is often at variance. According to European Union guidelines, the terms recommended to convey the likelihood of side-effects are as listed in Table 8.2, but most patients tend to overestimate the risks, leading to non-compliance. This is why it is important to explain the risks in the pharmacy. 

Bernstein et al. [8] addressed what types of patient education tools are currently used in international inherited metabolic disease clinics. A series of surveys were distributed to clinicians working with inherited metabolic disorders as well as to patients and families affected by PKU. The majority of clinicians (86.1 %) agreed that nutrition education affects dietary compliance in their patients. Perceived barriers to dietary compliance included embarrassment and/or frustration with the diet, poor family cohesion, difficulty in food preparation, and the inconvenience of the diet [8]. Clinicians from international clinics indicated one-on-one counseling is the most utilized educational tool regardless of patient age. The second most utilized educational tool reported was handouts and printed materials (Fig. 3.3). 

As previously mentioned, systemic delivery is limited because of the isolation of ocular tissues from the systemic circulation thus, topical delivery is often the preferred administration route owing to ease of access and patient compliance, particularly when treating infections of the anterior segment such as keratitis sicca, conjunctivitis, or blepharitis and diseases such as glaucoma or uveitis that require the drug to be diffused across the corneal barrier [19,20]. However, drainage, lacrimation and tear dilution, tear turnover, conjunctival absorption, and the corneal epithelium all limit corneal drug penetration [21,22]. 

Topical High patient compliance, self-administrable and noninvasive Higher tear dilution and turnover rate, cornea acts as barrier, efflux pumps, bioavailabihty <5%... 

Oral/Systemic Patient compliance and noninvasive route of administration Blood-aqueous barrier, blood-retinal barrier, high dosing causes toxicity, bioavailability <2%... 

Oral delivery is desirable due to the ease of administration, lower cost, and increased patient compliance. Despite these advantages, oral delivery of macromolecules is challenging due to low penetration across the intestinal epithelial barrier. To circumvent these barriers, drugs have been attached to mac-romolecular carriers such as dendrimers that can potentially aid in absorption across the intestinal epithelium. PAMAM dendrimers are effectively transported across epithelial barriers (Wiwattanapatapee et al. 2000 El-Sayed et al. 2002 Kitchens et al. 2006). SN-38, a potent anticancer drug, when complexed with PAMAM dendrimers showed increased solubility and uptake by Caco-2 cells (Kolhatkar et al. 2008). Orally administered anti-inflammatory drug ketoprofen in the form of PAMAM complexes (Man et al. 2006) prolonged activity and increased bio availability with a sustained release profile. 

The major obstacles for transmucosal delivery of insulin are the barrier properties of mucosa, rapid degradation, and limited absorption area [89,90]. Hence, strategies studied to overcome these obstacles include the use of materials that combine mucoadhesive, enzyme inhibitory and penetration-enhancing properties, which can improve patient compliance and prolong the contact time of drugs to mucosal membrane. However, further efforts are needed to design standardized in vitro and ex vivo biological... 

In CRA with alcohol-dependent patients, reinforcement of disulfiram compliance is one of the primary components of treatment, such that use of alcohol loses its reinforcing aspects and, in fact, becomes aversive. Furthermore, reinforcement from other sources is increased. Positive reinforcement for not drinking comes in the form of scheduhng other recreational activities and reorganizing daily life by breaking down pracrical barriers. For example, the therapist may assist the patient in obtaining a telephone, a place to hve, or transportation to treatment. 

Take measures to ensure compliance with medications and access to care. Compliance with medication regimens is a common problem for patients with epilepsy. Patients should be asked at every visit how they are taking their medications and if they missed any doses. Identify barriers to care, such as financial issues or transportation problems. 

Non-compliance issues appear more prevalent in some non-Western cultures. One study in South Africa revealed non-compliance rates to oral neuroleptics in two-thirds of Black patients and one-half of colored patients compared to only one-quarter of Caucasians (Gillis.Trollip, Jakoet etal., 1987). Cultural and communication factors were considered to be significant barriers apart from those related to cost and social factors. Kinzie et al. (1987) reported that despite prescribing adequate doses of tricyclic antidepressants (TCAs) to depressed Asian refugees,... 

Attempt to change patients medication orders when barriers to compliance exist Counsel patients on new and refill medications as necessary Promote patient wellness... 

Because the prescription and subsequent use of medications is shrouded in symbolism and social meaning, it is reasonable to expect that culture will exert powerful influences on pharmacological response. The clinician faces a series of obstacles when evaluating a Hispanic patient. Formulation of a diagnosis often proves extremely difficult, especially when the patient is unaccul-turated and language and other communication barriers are manifest. There are a number of adjustments psychiatrists can make, however, to maximize diagnostic accuracy and subsequent medication compliance. 

The patient is the most important source of information regarding their medication therapy. Although the data from the patient is subjective, the interview process can provide clarification on medications taken, knowledge of therapy, and barriers to education or compliance. 

Barriers to compliance must be identified during the history. Emotions, cognitive function, and physical ability can affect patient adherence to therapy. If a patient suffers from depression (emotional barrier), schizophrenia or dementia (cognitive barrier), or severe arthritis of the hands (physical barrier), compliance can diminish. Special attention should be given to these three areas, and barriers should be indicated on the history record. This process directs the implementation of specific aids to improve compliance. 

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