[The use of verospiron and the degree of platelet aggregation in arterial hypertension with abdominal obesity].

AIM: Comparative analysis of effects of hypothiazide and verospiron on platelet aggregation in patients with arterial hypertension and abdominal obesity. MATERIALS AND METHODS: Hypothiazide and verospiron were prescribed to 28 and 23 patients respectively for 16 weeks. The parameters estimated included dynamics of blood lipid profile, lipid peroxidation in plasma and platelets, antioxidant protection of the blood liquid fraction and platelets, platelet aggregation. The results were treated with the use of Student's t-test. RESULTS: Verospiron had positive influence on peroxidation syndrome and platelet aggregation. Its prolonged application maintained the achieved effect. Hypothiazide did not change the parameters of interest. CONCLUSION: Combined verospiron and non-medicamental therapy is recommended to reduce body mass in patients with arterial hypertension and abdominal obesity.

A First Report of HCTZ and Dicyclomine Induced Uncharacteristic Contraction Alkalosis.

Background: Contraction alkalosis is characterized by low serum sodium and chloride and high serum carbon dioxide and bicarbonate levels. Case Report: A 28-year-old Caucasian active-duty male with a history of autosomal dominant polycystic kidney disease and diarrhea-predominant Irritable Bowel Syndrome (D-IBS) presented to his primary care provider (PCP) with elevated blood pressure (136/96 mmHg), was diagnosed with stage-2 hypertension, and started oral HCTZ (25 mg/day). His medications included dicyclomine (10 mg oral three times daily). Subsequently, (Visit 1), his blood pressure was 130/91 mmHg and he was started on telmisartan (20 mg/day). At Visit 2, 4 weeks later, his blood pressure improved (121/73 mmHg); however, blood chemistry revealed elevated serum CO2 (32 mEq/L) and chloride (94 mmol/L). Four days later, the patient presented to the Emergency Department with dyspnea and swallowing difficulty. The patient returned to his PCP 3 days later complaining of cough, congestion, vomiting, and mild dyspnea, blood pressure of 124/84 mmHg. Two months later, sudden onset of projectile vomiting and abdominal pain while running was reported, resolved by rehydration and a single oral dose of prochlorperazine 25 mg. Three months later, (Visit 3), he complained of lightheadedness and cloudy judgment, suggesting contraction alkalosis. HCTZ was discontinued and telmisartan was increased to 20 mg twice daily. A follow-up blood chemistry panel 2 weeks later revealed serum chloride and CO2 levels within normal limits and blood pressure under 130/80 mmHg. Conclusion: This is the first known report of contraction alkalosis driven by drug-drug interaction between dicyclomine and HCTZ.

Chlorthalidone versus hydrochlorothiazide for preventing cardiovascular disease in hypertension: Is the case closed?

The optimal diuretic choice [hydrochlorothiazide (HCTZ) or chlorthalidone (CTD)] for the management of hypertension has been an ongoing debate for several years. HCTZ is widely used in the form of single-pill combinations, whereas CTD is a more potent drug vs. HCTZ, especially in reducing nighttime blood pressure (BP), with some indirect evidence suggesting a superiority in terms of cardiovascular (CV) risk reduction. In addition, recent data showed that CTD was safe and effective in terms of BP lowering in predialysis patients with stage 4 chronic kidney disease. The Diuretic Comparison Project was the first head-to-head pragmatic, open-label trial that randomly assigned elderly patients with hypertension under HCTZ therapy to continue with HCTZ or to switch to CTD (equivalent doses). Office BP was similar for both groups throughout the study. The trial showed no difference in major CV events or non-cancer-related deaths during a median follow-up of 2.4 years; yet, CTD was associated with a benefit in participants with a previous myocardial infarction or stroke, which might be a chance finding but could also indicate that a high-risk population is more suitable for revealing the impact of slight differences in the 24-hour BP profile in a relatively short-term follow-up. Interestingly CTD vs. HCTZ was associated with higher hypokalemia rates apart from the latter group of patients where there was no difference. Overall, the available data do not confirm the superiority of CTD over HCTZ in general, but this could be questionable in selected patients.

Effects of losartan/hydrochlorothiazide treatment, after change from ARB at usual dosage, on blood pressure and various metabolic parameters including high-molecular weight adiponectin in Japanese male hypertensive subjects.

Losartan, an angiotensin II receptor blocker (ARB), has been reported to increase serum level of high-molecular weight (HMW) adiponectin, which has beneficial effects on insulin resistance and atherosclerosis. On the other hand, treatment with diuretics was reported to decrease the adiponectin level. In the present study, we investigated the effects of changing the treatment to losartan/hydrochlorothiazide (HCTZ) on blood pressure (BP) and various metabolic parameters in Japanese male hypertensive subjects. This study included 15 subjects whose therapy was changed from a usual dosage of ARB to losartan 50mg/HCTZ 12.5mg daily, and also 14 subjects who continued losartan treatment (50mg/day). Serum HMW-adiponectin concentration was assayed using a commercially available HMW-specific ELISA kit. In the losartan/HCTZ patient group, systolic/diastolic BP decreased from 146/95 to 130/84 mmHg (P = 0.0012 for both). The HbA1c level tended to increase from 5.44 ± 0.39 to 5.55 ± 0.44% (P = 0.0554) and serum creatinine level slightly increased from 0.82 ± 0.12 to 0.87 ± 0.12 mg/dl (P = 0.0015). In contrast, serum TG (125 ± 77 to 149 ± 112 mg/dl), uric acid, and HMW-adiponectin levels (3.24 ± 2.97 to 3.36 ± 2.43 µg/ml) were unchanged. In the 14 patients who continued losartan treatment, systolic/diastolic BP was unchanged from 134/86 to 129/80 mmHg. The HbA1c level tended to increase from 5.26 ± 0.63 to 5.39 ± 0.71% (P = 0.0880), serum creatinine and uric acid levels were unchanged, serum lipids tended to improve, and serum HMW-adiponectin levels increased from 3.03 ± 1.06 to 3.46 ± 1.28 µg/ml (P = 0.0105). In summary, changing treatment to losartan/HCTZ, when changed from a usual dosage of ARB, exerted good BP control, while the HMW-adiponectin level was unchanged in male hypertensive subjects.

Combining angiotensin receptor blockers with chlorthalidone or hydrochlorothiazide - which is the better alternative? A meta-analysis.

BACKGROUND: Hypertension is a disease with significant clinical and socio-economic consequences. The reduction in cardiovascular mortality and morbidity in patients treated for hypertension is directly related to the magnitude of blood pressure reduction. Diuretics have proven useful for the prevention of cardiovascular complications in addition to a long history of safety and efficacy. The main aim for this meta-analysis is to compare the efficacy of the combination of angiotensin receptor blocker (ARB) and chlorthalidone (CTLD) to the combination of ARB and hydrochlorothiazide (HCTZ) in patients with hypertension. METHODS: A comprehensive literature search was conducted through electronic databases PubMed, MEDLINE, Scopus, PsyInfo, Cochrane, eLIBRARY.ru, http://ClinicalTrials.gov and http://www.clinicaltrialsregister.eu in July 2020 to identify studies that investigate the effect of the combination of angiotensin receptor blocker with chlorthalidone or hydrochlorothiazide on the systolic and diastolic blood pressure in patients with hypertension. Changes in systolic and diastolic blood pressure (BP) expressed as a weighted mean difference (WMD) were our primary outcomes. The random-effects method was chosen as the primary analysis and results were presented with a 95% confidence interval (CI). Sensitivity analysis was performed and bias was assessed. RESULTS: Our search returned 2745 titles. Of them, 51 full-text articles remained to be subjected to assessment. Comparisons of ARB/HCTZ versus ARB showed changes in BP of -6.89 (-8.09, -5.69) mmHg for systolic BP and - 3.67 (-4.15, -3.19) mmHg for diastolic BP. For the ARB/CTLD versus ARB/HCTZ comparison changes were - 6.30 (-7.30, -5.29) mmHg for systolic BP and - 3.57 (-4.17, 2.98) mmHg for diastolic BP. CONCLUSION: Our analysis suggests a small but significant favor for CTLD in blood pressure control when compared to HCTZ. We believe it should be considered as a valuable alternative for HCTZ and an option for fixed dose combinations with an ARB although further research is required.

Renoprotect and blood pressure lowering effect of low-dose hydrochlorothiazide added to intensive renin-angiotensin inhibition in hypertensive patients with chronic kidney disease.

OBJECTIVES: Combination therapy with angiotensin II Type I receptor blocker 50 mg of losartan and a fixed combination of losartan (50 mg)/hydrochlorothiazide (12.5 mg) was administered to hypertensive patients with Stage 3 - 4 chronic kidney disease to investigate its renoprotective effect. METHODS: Subjects already being administered the angiotensin I-converting enzyme inhibitor enalapril and losartan 100 mg daily were enrolled in this open-labeled trial (n = 40). Administration of 100 mg losartan twice daily was replaced with losartan (50 mg)/hydrochlorothiazide (12.5 mg) once daily after the morning meal and losartan at 50 mg once daily after the evening meal for the 24-week study period. RESULTS: The mixture of losartan/hydrochlorothiazide significantly reduced systolic and diastolic blood pressures by 14.7 and 7.4 mmHg, respectively, compared with the baseline values. No significant changes were observed in the serum creatinine levels and estimated glomerular filtration rate. The urinary protein/creatinine ratio was, however, significantly decreased. Similarly, the regression line of 1/serum creatinine level was significantly increased after administration of losartan/hydrochlorothiazide. None of the patients exhibited a significant increase in the occurrence of adverse effects. CONCLUSIONS: Our results demonstrated that a low dose of hydrochlorothiazide had a renoprotective effect due to its blood pressure-lowering effect. We accordingly propose that a low dose of hydrochlorothiazide should be administered to those patients in whom the blood pressure is not well controlled by intensive renin-angiotensin system inhibition therapy using the maximum recommended doses of angiotensin II Type I receptor blockers and angiotensin I-converting enzyme inhibitors.

Pharmacodynamics of kardos administered as monotherapy and in combination with hypothiazide and enalapril in grade I-II arterial hypertension.

Therapy with kardos produced an antiihypertensve effect in patients with grade I-II arterial hypertension. This antiihypertensve effect was considerably potentiated, when kardos was administered in combination with enalapril.

Thiazide increases serum calcium in anuric patients: the role of parathyroid hormone.

We evaluated the effect of hydrochlorothiazide in a sample of anuric patients on hemodialysis and found an increase in serum calcium, which occurred only in those with parathyroid hormone >300 pg/ml. This finding highlights the extra-renal effect of this diuretic and a possible role of parathyroid hormone in the mechanism. PURPOSE: Thiazide diuretics are commonly used in patients with chronic kidney disease to treat hypertension. Their effects on calcium and bone metabolism are not well established, once calciuria may not fully explain levels of calcium and parathyroid hormone (PTH) in this population. A previous study has suggested that thiazides require the presence of PTH as a permissive condition for its renal action. In anuric patients, however, the role of PTH, if any, in the thiazide effect is unknown. METHODS: To assess thiazide extra renal effect on serum calcium and whether such an effect is reliant on PTH, hydrochlorothiazide (HCTZ) 100 mg was given orally once a day to a sample of 19 anuric patients on hemodialysis for 2 weeks. Laboratories' analyses were obtained in three phases: baseline, after diuretic use, and after a 2-week washout phase. RESULTS: We demonstrated that serum calcium (Ca) increased in ten patients (52.6%) after HCTZ use, returning to previous levels after the washout period. Out of the 19 patients, ten presented PTH ≥ 300 pg/ml, and Ca has increased in eight of them, whereas in the other nine patients with PTH < 300 pg/ml, serum Ca has increased only in two individuals (RR risk of increase Ca 3.9; p = 0.012). CONCLUSIONS: HCTZ was capable of increasing serum Ca in a sample of anuric patients on hemodialysis and seems this effect is highly dependent on PTH levels. Caution is required while interpreting this result, as the small sample size might implicate in a finding caused by chance.

Effects of non-steroidal anti-inflammatory drugs on hypertension control using angiotensin converting enzyme inhibitors and thiazide diuretics.

OBJECTIVES: To determine the impact of three non-steroidal anti-inflammatory drugs on the efficacy of two anti-hypertensive drugs. DESIGN: Fifteen women with arthritis and hypertension who were receiving lisinopril and HCT, and administered sequentially in random order ibuprofen, sulindac, and diclofenac for one month each, with an intervening two-week washout period between each treatment period. During the washout period, subjects received paracetamol. SETTING: Hypertension Clinic, Medical Centre, Harare, Zimbabwe. SUBJECTS: Fifteen female hypertensive women with documented arthritis. MAIN OUTCOME MEASURES: Blood pressure at the end of two weeks of paracetamol was compared with blood pressure after one month of treatment with each of the NSAID. RESULTS: Mean blood pressure was unchanged before and after all NSAIDs: 108 +/- 7 versus 107 +/- 9 for diclofenac, 108 +/- 9 versus 108 +/- 9 for sulindac, and 108 +/- 8 versus 107 +/- 9 for ibuprofen. The 24 hour urinary sodium excretion was not significantly different. CONCLUSION: The three NSAIDs investigated did not neutralise the antihypertensive effect of the combination of lisinopril and HCT, and hence the blood pressure lowering action of the combination may not be prostaglandin dependent.

Hydrochlorothiazide vs. chlorthalidone as the optimal diuretic for the management of hypertension.

Even though hydrochlorothiazide (HCTZ) and chlorthalidone are frequently considered interchangeable antihypertensive agents, they appear to differ both in their blood pressure lowering efficacy and in their effects on the lipid profile and on serum potassium, uric acid and glucose levels. More importantly, in randomized controlled trials, chlorthalidone was equally or more effective than other antihypertensive agents in cardiovascular risk reduction whereas treatment with HCTZ yielded conflicting results. Although there are no randomized trials comparing the effects of these two agents on cardiovascular events, retrospective data from the Multiple Risk Factor Intervention Trial suggest that chlorthalidone might reduce cardiovascular morbidity more than HCTZ. However, current guidelines do not consistently recommend one or the other and it remains to be established which one is the diuretic of choice.

Significance of estimated salt excretion as a possible predictor of the efficacy of concomitant angiotensin receptor blocker (ARB) and low-dose thiazide in patients with ARB resistance.

The purpose of this study was to assess the factors affecting the efficacy of combination therapy with losartan and thiazide, with a focus on the significance of salt excretion, via a multicenter observational study. Adult patients with essential hypertension showing therapy resistance to angiotensin receptor blocker (ARB) as a monotherapy or in combination with Ca channel blockers (CCB) were enrolled, and their previously administered ARBs were replaced with the combination tablet containing losartan (50 mg per day) and hydrochlorothiazide (12.5 mg per day). Blood pressure and biochemical parameters were monitored for a year. The baseline blood pressure (153.4±14.8/86.4±11.3 mm Hg) was significantly lowered at the 3rd month (137.3±17.4/78.2±11.1 mm Hg, n=93) and was maintained at this lower level until the 12th month (135.3±14.0/76.4±11.1 mm Hg, n=74). The baseline value of estimated salt excretion (eSE), calculated using Tanaka's formula, differed significantly between the high and low treatment response groups, which were defined by the average change in mean blood pressure (MBP-C, -11.3 mm Hg; eSE=10.8±2.9 g per day in high responders vs. 9.2±2.3 g per day in low responders, P=0.004). Univariate and multivariate analyses showed a significant correlation between eSE and MBP-C (R=-0.288, P=0.007) and indicated the clinical effectiveness of eSE as a possible predictor for MBP-C (P=0.021). In addition, the urine Na-to-Cr ratio (NCR) demonstrated significant correlations with eSE (R=0.848, P<0.001) and MBP-C (R=-0.344, P<0.001). These results suggest that eSE or NCR could, to a certain extent, predict the efficacy of combination therapy with losartan and low-dose thiazide in patients demonstrating ARB resistance. Combination therapy with losartan and thiazide might thus be suitable for patients with a large amount of salt excretion.

Combination therapy for hypertension: focus on high-dose olmesartan medoxomil (40 mg) plus hydrochlorothiazide.

IMPORTANCE OF THE FIELD: Cardiovascular disease is a major cause of premature death and disability worldwide, and effective blood pressure (BP) control is crucial for the reduction of cardiovascular risk in patients with hypertension. Despite this, many will fail to attain recommended BP goals. A reappraisal of European guidelines led to revised recommendations for BP reduction to values within the SBP/DBP range of 130 - 139/80 - 85 mmHg in all patients with hypertension, including higher-risk groups such as those with diabetes. AREAS COVERED IN THIS REVIEW: The majority of hypertensive patients will require the enhanced blood-pressure-lowering effects of at least two antihypertensive drugs with complementary mechanisms of action to achieve these goals. WHAT THE READER WILL GAIN: The angiotensin II receptor blocker (ARB) olmesartan medoxomil and the thiazide diuretic hydrochlorothiazide (HCTZ) provide greater antihypertensive efficacy when used in combination than as monotherapy with either component, with a similar tolerability profile. In addition, there is evidence that higher doses of olmesartan may prolong the antihypertensive effect of this ARB, and a number of US 'treat-to-target' and European add-on clinical trials have been conducted to assess the efficacy and safety of high-dose olmesartan plus HCTZ in a wide range of patients with mild-to-severe hypertension. TAKE HOME MESSAGE: Combination therapy with olmesartan, including the high 40-mg dose, plus HCTZ is an effective and safe treatment option for controlling BP in patients with mild-to-severe hypertension, particularly those who fail to achieve recommended BP goals with monotherapy.

Olmesartan medoxomil plus hydrochlorothiazide for treating hypertension.

Although achieving blood pressure (BP) control is critical to improve cardiovascular prognosis in hypertensive patients, many of them fail to attain the targets. Most patients with hypertension need more than one antihypertensive agent to achieve the goals. Combination therapy is required when monotherapy fails to attain BP objectives (< 140/90 mmHg in general hypertensive population; < 130/80 mmHg in high-risk groups) and as a first-line treatment in certain situations, such as markedly elevated BP values, high or very high cardiovascular risk patients or when lower targets are warranted. The advantages of combination therapy are well documented with the potential for increased antihypertensive efficacy as a result of different mechanisms of action, and a lower incidence of adverse effects because of the lower doses used and the possible compensatory responses. The inhibition of the renin-angiotensin system appears to be very beneficial in the treatment of patients with hypertension. Olmesartan medoxomil 20 mg/hydrochlorothiazide 12.5 mg is the latest combination of an angiotensin receptor blocker and a diuretic approved for treatment of hypertension. The aim of this manuscript is to update the published data about the efficacy and safety of this fixed combination.

Is hydrochlorothiazide-induced hypocalciuria due to inhibition of prostaglandin E2 synthesis?

1. Since prostaglandin E2 could play a role in idiopathic hypercalciuria, and considering the well-established hypocalciuric action of hydrochlorothiazide, we have evaluated the effect of 15 days' treatment with hydrochlorothiazide in 10 hypercalciuric male stoneformers on urinary Ca2+ and prostaglandin E2, as well as on plasma bicyclo-prostaglandin E2, 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D and parathyroid hormone. 2. In addition to lowering urinary Ca2+ (P less than 0.001), hydrochlorothiazide also promoted a significant fall in urinary prostaglandin E2 (P less than 0.001), plasma bicyclo-prostaglandin E2 (P less than 0.001) and 1,25-dihydroxyvitamin D (P less than 0.01), and an increase in plasma parathyroid hormone (P less than 0.025), whereas plasma 25-hydroxyvitamin D was unchanged. 3. A positive correlation between urinary Ca2+ and prostaglandin E2 was present before (P less than 0.00005), but not after, hydrochlorothiazide. Plasma bicyclo-prostaglandin E2 and plasma 1,25-dihydroxyvitamin D were positively correlated both before (P less than 0.005) and after (P less than 0.005) hydrochlorothiazide, as was also the percentage change in each induced by the drug (P less than 0.05). Furthermore, the changes in plasma 25-hydroxyvitamin D and plasma 1,25-dihydroxyvitamin D after hydrochlorothiazide were negatively correlated (P less than 0.05). 4. It is suggested that a block of prostaglandin E2 synthesis plays a role in the effect of hydrochlorothiazide on Ca2+ metabolism, most probably through an inhibition of 1 alpha-hydroxylase activity.

Effect of hydrochlorothiazide on urine saturation with brushite, in vitro collagen calcification by urine, and urinary inhibitors of collagen calcification.

To clarify further the beneficial effect of thiazide diuretics on recurrent calcium nephrolithiasis, the effect of short-term hydrochlorothiazide therapy on urine saturation with brushite (CaHPO(4).2H(2)O), in vitro collagen calcification by urine, and urinary inhibitors of calcification was studied.In 22 patients with idiopathic calcium oxalate/phosphate stones the urine calcium excretion decreased, the urine magnesium excretion increased and the urine magnesium/calcium ratio increased significantly (P < 0.001) during hydrochlorothiazide therapy. Supersaturation of the urine with brushite, which was present in 19 of the 22 patients, was reduced significantly (P < 0.001) in all during thiazide therapy, and to the undersaturated range in 16. The ability of urine to calcify collagen in vitro also decreased significantly (P < 0.001) during thiazide therapy, a change that correlated significantly (r = 0.4513, P < 0.05) with the decrease in brushite saturation. The concentration of urinary inhibitors of calcification, as determined with an in vitro collagen calcification system, was decreased significantly (P < 0.01) by thiazide therapy.It was concluded that, in addition to decreasing urine calcium excretion and increasing urine magnesium excretion, thiazide diuretics decrease the urinary brushite saturation and thus may prevent spontaneous nucleation or crystal growth, or both, of calcium phosphate. The ability of thiazides to decrease collagen calcification in vitro suggests that they may also prevent crystal growth on a nidus of organic matrix. Thiazides do not appear to act by increasing the excretion of urinary inhibitors of calcification.

The potential economic consequences of cognitive improvement with losartan.

In a clinical trial, treatment of mild-moderate hypertensive patients with losartan (50 mg) increased Mini-Mental State Examination (MMSE) scores by 4 points from baseline over a 26-month period, compared with a 1-point increase in patients treated with hydrochlorothiazide (25 mg). This study explores the potential economic consequences of this improvement in cognitive function in a population of elderly hypertensive patients in Sweden. Resource use and MMSE data for 437 hypertensive, non-demented subjects aged 75 years and above, were taken from a population-based study in Sweden. MMSE scores were strongly related with costs of care due to higher utilization of home help and special living arrangements in patients with low scores. A 1-point difference in MMSE was associated with a difference in the annual cost of care of approximately 5700 Swedish kronor (SEK). Over 26 months, the potential cost savings from the 4-point improvement observed with losartan was estimated to be between 24700 and 43700 SEK. This can be compared with the acquisition cost of losartan; approximately 5700 SEK over the study period. Thus, an improvement in cognitive function of the magnitude documented in the study of losartan vs hydrochlorothiazide, may translate into economic benefits beyond those expected in terms of blood pressure control.

Beta-blocker versus diuretic for control of the blood pressure response to stress in hypertensive patients.

To compare the antihypertensive effects of beta-blockers and diuretics on the blood pressure increase to stress, a randomized single-blind crossover study was performed in 27 patients with mild or moderate hypertension. At the initial examination and after two subsequent periods of therapy with 100 mg atenolol or with a combination of 50 mg hydrochlorothiazide and 5 mg amiloride hydrochloride, once a day, blood pressure and heart rate were measured at rest, during mental arithmetic, sustained handgrip and cycloergometric test. Both treatment significantly decreased supine and standing systolic and diastolic pressure at rest, during and immediately after mental stress and isometric exercise, with the reduction of diastolic pressure significantly greater after atenolol. During dynamic exercise, systolic and diastolic pressures were significantly decreased by diuretics at the lowest work-load only, whereas beta-blocker caused significant and greater blood pressure reductions throughout the exercise. The combination of two classes of drug normalized resting blood pressure in 8 of 9 subjects in which the monotherapy had failed to obtain values less than 140/90 mmHg and gave a better control of systolic and diastolic pressures throughout all the stress tests. It is concluded that atenolol is more effective than diuretics during stress, suggesting that beta-blocking drugs are the first choice treatment for mild to moderate hypertension and that when the antihypertensive effect of a single agent is insufficient, a combination of beta-blockers and diuretics is also effective during stress.

Interacciones potenciales de fármacos antihipertensivos en un año de estudio de pacientes con hipertensión arterial atendidos en hospitales de 11 municipios del Departamento de Risaralda-Colombia / Antihypertensive medicaments potential interactions in one year of study in hypertensive patients attended in hopitals from 11 country of the Risaralda Department-Colombia

En enfermedades como la hipertensión arterial con frecuencia deben utilizarse tratamientos con dos o más medicamentos, por lo cual el uso incorrecto de ellos puede conllevar a interacciones de fármacos. En el contexto de la hipertensión arterial en América Latina, existen escasos estudios evaluando la magnitud de este problema. Se realizó el presente estudio, observacional, transversal, con un muestreó censal, con el fin de establecer la ocurrencia de potenciales interacciones de fármacos en pacientes con hipertensión arterial de hospitales de 11 municipios de Risaralda, Colombia, agosto 2009 a agosto 2010, usando un algoritmo diseñado para identificar posibles interacciones de fármacos. Se obtuvieron 65.535 registros de prescripción de antihipertensivos, de 3.813 pacientes hipertensos, 28,46% correspondieron con hidroclorotiazida y 2007% enalapril, entre otros. Del total de pacientes 17,60% (IC95% 16,34%-18,82%) presentaron interacciones potenciales de fármacos, siendo la mayor en el municipio Dosquebradas (21,09%; IC95% 18,79%-23,36%). La interacción más frecuente fue enalapril-hidroclorotiazida (45,58% de los pacientes) y la de mayor riesgo y frecuencia fue enalapril-espironolactona (2,41%). estos resultados, reflejan en parte, falta de cumplimiento de normas de tratamiento de la hipertensión arterial, asi como poca implementación de conductas de tratamiento basadas en evidencia, y también posiblemente dificultades en la formación universitaria, falta de programas de educación médica continuada, falta de interés y tiempo para acceder a los alertas y reportes de nuevas condicones de uso de los medicamentos y poca instrucción y enseñanza de la medicina basada en evidencias, aspectos sobre los cuales se debe intervenir integralmente con distintos enfoques

In diseases such as hypertension, commonly treatments with two or more drugs should be used, then their incorrect use can lead to drug interactions. In the context of the hypertension in Latin America, there are few studies assessing the magnitude of this problem. Current, observational, cross-sectional and census study was made in order to establish the potential ocurrence of drug interactions in patients with hypertension from hospitals of 11 municipalities of Risaralba, Colombia, august 2009 to august 2010, using an algorithm designed to identify possible drug interactions. A total of 5.535 antihypertensive prescription records from 3.813 hypertension patients, 28.46% corresponding to hydrochlorothiazide and 20.07% to enalapril, among others, were obtained. From the total of patients 17.60% (95% CI 16.34 %-18.32%) presented potential drug interactions, being highest at the municipality Dosquebradas (21.09%; 95% CI 18.79%-23.36%). Most frequent interaction was enalapril-hydrochlorothiazide (45.58% of patients) and that of higher risk and frequency was enalapril-spironolactone (2.41%). These results, reflected in part, the lack of adherence to hypertension treatment guidelines, as well few implementation of evidenced based treatment conducts, and possibly too defficulties in the university formation, lack of continue medical education programs. Lack of interest and time to access to the alerts and reports of new conditions of drugs use and few instructions and teaching of evidence based medicine, aspects that needs tobe integrally intervened with different approaches