A couple of factors influence pharmacodynamic and pharmacokinetic processes. For instance, age, genetics, behaviors, and ethnicity. Aging is designated by accelerated impairment of functional capabilities of entire organ systems, diminished homeostatic mechanisms, and altered reaction to receptor stimulation (Peeters et al., 2019). The aforementioned processes influence the pharmacodynamic and pharmacokinetic processes with the resultant need for dose adjustments or rather contraindication of some pharmacologic agents in the elderly. Additionally, aging is associated with a reduction in the first-pass metabolism attributed to a decrease in the liver bulk and blood flow. Similarly, impaired hepatic and renal functions correlated with aging significantly hinder the renal and hepatic clearance of a majority of drugs (Laurent, 2017). Consequently, in the case of AO, 86-year-old taking atenolol, simvastatin, sertraline, hydralazine, and doxazosin, the bioavailability of the mentioned drugs will increase.
According to Peeters et al. (2019), aging is further associated with a reduction in cumulative muscle mass and total body water but with an increase in the percentage of body fat. As a result, the volume distribution of lipid-soluble drugs increases while it decreases for non-lipid soluble drugs. Pharmacodynamically, on the other hand, aging is accompanied by altered sensitivity to drugs with a general increase in sensitivity to drugs in the elderly. Ultimately, adjustments of the doses AO’s drug regimen are critical to avoid adverse side effects or rather toxicity.
Atenolol which is indicated for therapeutic management of hypertension is largely metabolized by the liver and excreted by the kidney. Subsequently, the dose will be adjusted depending on the renal and liver function. Similarly, geriatric patients have decreased sensitivity to beta-blockers due to increased total peripheral resistance, and reduced cardiac and pulmonary function (Khalil & Zeltser, 2021). Therefore, the beta-blocker should be substituted with another class of antihypertensive. On the other hand, doxazosin also metabolized by the liver is associated with hypotension when utilized in the geriatric population and thus will necessitate periodic monitoring of vital signs and dose adjustments (Khalil & Zeltser, 2021). Sertraline should be avoided in adolescents and children due to an increased risk of suicidal ideation. It is a good agent in the elderly as it reduces stress and depression which significantly perpetuate hypertension. It is a vital medication in the elderly as it reduces symptoms of BPH. Hydralazine dose should be adjusted depending on the individualized rate of acetylation. Lastly, the safety profile of simvastatin, atenolol, and doxazosin has not been established in children less than 10 years.
Patient AO is a geriatric hypertensive hyperlipidemic patient and at risk of BPH, therefore being on doxazosin is crucial. This medication reduces the blood pressure and symptoms of BPH in addition to decreasing LDL and cholesterol (Redon & Redon, 2019). However, this therapeutic agent is associated with orthostatic hypotension and edema especially in the elderly. Consequently, I will periodically monitor the vital signs, weight, edema, and liver function tests of AO and reduce the dose accordingly. I will gradually taper down the dose while simultaneously monitoring the adverse effects. Atenolol is relatively contraindicated in the elderly and therefore I will consider substituting it with a first-line antihypertensive such as hydrochlorothiazide(Redon & Redon, 2019). AO has gained 9 pounds which might be due to edema associated with atenolol and doxazosin, therefore, a diuretic such as hydrochlorothiazide when deployed will control the blood pressure as well as edema (Redon & Redon, 2019).
The doses of sertraline, hydralazine, and simvastatin will remain unadjusted. However, the patient will be assessed periodically and educated on the importance of taking medications as advised by the healthcare provider. Similarly, I will educate the patient on the side effects associated with these medications such as sexual dysfunction, fatigue, diarrhea, and drowsiness, and the need to consult the care provider if the symptoms persist or become intolerable (Redon & Redon, 2019). Additionally, I will advise and educate the patient on lifestyle modification and behavior changes to help control hypertension such as diet modification, smoking, and alcohol cessation, and regular physical activity. Finally, I will follow up with the patient at the medical outpatient clinic.