Pharmacology. Case Study

Pharmacology. Case Study


Thiazide classes of drugs for the treatment of hypertension are preferred types of medication, but they are underused in the United States. Thiazide categories of drugs cause an increase in hypokalemia and renal failure. The frequently used thiazide in America is hydrochlorothiazide (HCTZ). The drug is used at a dose range of 25 to 50 mg per day. Thiazide drugs are also utilized in the treatment of edema associated with kidney, liver and heart disease(Beyer KH, 1993). Thiazide related diuretics, as well as thiazide, reduce the risk of heart failure, heart attack, stroke, and death as a result of hypertension. These classes of drugs were discovered in the year 1950s and were developed by Merck and Co. Chlorothiazide was soldusing the name Diuril at the commencement of 1958 after the approval as the first class of Thiazide. The drugs are affordable and available in most countries.  Thiazide classes of diuretics are delivered from benzothiadiazide(Brown et al., 2016). They regulate hypertension through controlling the reabsorption of ions such as chloride and sodium in the kidney. They inhibit the reabsorption of these ions from the distal convoluted tubules. The term thiazide is employed in drugs with the same mechanism of action but without thiazide chemical structure such as metolazone and chlorthalidone. These drugs are referred to as thiazide-like diuretics.

Is there a better medication than a thiazide, and if so what dose should you initiate this medication?

The evidence available now encourages the use of thiazide-based on the criteria of cost and effectiveness. Based on the criteria of convenience, tolerability, and efficacy, thiazide is better compared to other types of medications. For patients with less complication and with hypertension, thiazide is a drug of choice.  The drug may be ineffective or inappropriate to approximate 25% of the patients. In these types of patients, other effective drugs for controlling hypertension need to be included during treatment.

How to proceed

Thiazide diuretics escalates the reabsorption  at the distal tubules of the calcium ions.Within the epithelial cells, the lower the concentration of sodium thereby increasing the action of the sodium/calcium ions antiporter on the basolateral membrane. These favors the transportation of calcium into the interstitium. The intracellular concentration of calcium is significantly reduced thus favoring the diffuse of calcium via apical calcium ions selective channels (TRPV5). The driving force of the calcium reabsorption at the lumen is favored by decreased calcium concentration in the cells(Brown et al., 2016). Thiazide increase also the calcium reabsorption through a mechanism that involves the sodium and calcium reabsorption in the proximal tubules. This takes place in response to the depletion of the sodium ions. These responses occur as a result of augmentation of the activity of parathyroid hormone(Dhalla et al., 2016)

. Thiazide can be employed in the treatment of hypertension except in diabetic patients who cannot regulate their blood sugars in an appropriate manner. Thiazide used is associated with elevated levels of uric acid. The drug should be used in patients who may develop recurrent gout related to thiazide therapy.


Elliot should take 25mg of hydrochlorothiazide orally on the dairy basis.  Importantly, the dose may increase to 50 as a single dose. 25 mg should be taken twice per day. It is paramount to monitor the electrolyte levels of Eliot on a daily basis as a result of his age. He should take the dose early in the morning and another dose at 6 pm if he is taking the 25mg tablets.


How to monitor toxicity and efficacy


The efficacy of the drug can be tested through monitoring of the blood pressure on regular basis. Additionally, it is also important to monitor for any adverse side effects. For instance, blood work can be ordered to facilitate the monitoring of the levels of electrolyte, triglyceride, cholesterol, blood glucose and lithium in the body(Dhalla et al., 2016)

. The lithium toxicity can take place as a result of hydrochlorothiazide reduction of the lithium elimination mechanism. The drug may change the glucose intolerance in addition to raising the triglycerides and cholesterol levels in the body. Monitoring the levels of serum in Eliot blood is paramount.


Comprehensive lab work is required in the monitoring of the lithium levels, lipid panel, uric acid, the metabolic panel in the body. The drug may increase the level of serum uric acid as a result of the clearance of uric acid thereby causing gout and hyperuricemia in patients (Kaufman, 2014). Lower electrolytes levels cause heart rhythms abnormalities hence the need to monitor the levels in Eliot blood(Dhalla et al., 2016). They may decrease the urinary calcium extension, and this may cause mild elevation of calcium levels in the body. Eliot should be advised to reduce the intake of sodium from the diet and should be educated for dehydration signs that include dry mouth.





Beyer KH (1993). “Chlorothiazide. How the thiazides evolved as   antihypertensive therapy”. Hypertension 22 (3): 388– 91. doi:10.1161/01.hyp.22.3.388. PMID 8349332.

Brown, M. J., Williams, B., Morant, S. V., Webb, D. J., Caulfield, M. J., Cruickshank, J. K., … & Mackenzie, I. S. (2016). Effect of amiloride, or amiloride plus hydrochlorothiazide, versus hydrochlorothiazide on glucose tolerance and blood pressure (PATHWAY-3): a parallel-group, double-blind randomized phase 4 trial. The Lancet Diabetes & Endocrinology4(2), 136-147.

CD001841.doi:10.1002/14651858.CD001841.pub2. PMID 19588327.

dential Care,16(2), 83-86

Dhalla, I. A., Gomes, T., Yao, Z., Nagge, J., Persaud, N., Hellings, C., …&Juurlink, D. N. (2013). Chlorthalidone Versus Hydrochlorothiazide for the Treatment of Hypertension in Older AdultsA Population-Based Cohort Study. Annals of internal medicine158(6), 447-455.

Kaufman, G. (2014). Diuretics: How they work, cautions and contraindications. Nursing &Resi

sion”. Cochrane Database Syst Rev 8 (3):

Wright JM, Musini VM (July 2009). Wright, James M, ed. “First-line drugs for hyperten