Gene/Protein Disease Symptom Drug Enzyme Compound
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 147,016 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Aspirin (acetylsalicylic acid) and its salicylate derivatives are effective antipyretic, analgesic, and anti-inflammatory agents that are still very widely used by the elderly despite the advent of newer, potentially safer nonsteroidal anti-inflammatory drugs (NSAIDs). However, none of the new NSAIDs have been proven to be more effective than aspirin or salicylic acid. Chronic salicylate intoxication which is most common in the elderly, may occur with therapeutic doses. Increased toxicity in older patients often appears due to inadvertent overdosage. Dual prescribing or additional use of nonprescription salicylates are some causes of unwitting long term toxicity. According to some studies, systemic clearance of salicylate (mainly by hepatic metabolism) is reduced with age, as is renal elimination. These changes are of increased importance in the elderly using high therapeutic doses of salicylates when metabolism is saturated and more unchanged drug is available for renal excretion. In the face of renal impairment, the risk of toxicity is increased. The diagnosis of acute salicylate intoxication generally does not pose diagnostic problems. Patients often present with a history of intentional overdose, with hyperventilation, fever, and nausea. The diagnosis can be confirmed by measuring serum salicylate concentrations. Chronic intoxication often poses a diagnostic dilemma with atypical presentations mimicking other disease states such as diabetic ketoacidosis, delirium, cerebrovascular accident, myocardial infarction or cardiac failure. The diagnosis of salicylate intoxication should be borne in mind when an older patient presents with recent deterioration in activities of daily living with no known cause. Plasma salicylate concentrations should be measured if salicylate intoxication is suspected, even if there is no documented history of salicylate ingestion. The risk of salicylate nephrotoxicity is also increased with age, and upper gastrointestinal haemorrhage is associated with increased mortality in older age groups. Treatment of acute toxicity consists of prompt recognition of salicylate intoxication, use of activated charcoal, correction of acid-base abnormalities, general supportive measures, and if concentrations are extremely high, dialysis can be effectively used. Chronic toxicity, which can occur even with marginally high salicylate concentrations, is treated with drug withdrawal and supportive therapy. Chronic salicylate toxicity can be averted by prescription of conservative doses of drug, avoidance of concomitant use of different salicylate preparations, and therapeutic monitoring to guide dosage. Renal function should be monitored to detect nephrotoxicity from chronic salicylate therapy. Patients should be regularly screened for evidence of gastrointestinal bleeding.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Salicylate intoxication in the elderly. Recognition and recommendations on how to prevent it. 155 71

The aim of this study was to assess the minimum time interval necessary to avoid the development of tolerance during nitroglycerin patch application. We studied 24 patients, aged 23 to 73 years, with ischemic or idiopathic dilated cardiomyopathy (LV EF less than 0.40) and stable clinical conditions during 30 days before the study. All patients had significant reduction of systemic and pulmonary arterial pressure after sublingual nitroglycerin. After the hemodynamic assessment of the response to the first dose of the nitroglycerin patch, the patients were randomized to 1 of 3 chronic treatment groups: continuous patch application (Group A), intermittent application with 4 hours intervals (Group B), intermittent application with 6 hours intervals (Group C). All patients were studied by right heart Swan-Ganz catheterization; the hemodynamic response to a 10 mg multilayer matrix nitroglycerin patch was assessed before and every hour, in the next 4 hours, after both the first application of the patch and after 1 month of therapy; after chronic intermittent therapy, hemodynamic parameters were also measured 24 hours after drug withdrawal. Hemodynamic parameters were significantly changed after the first nitroglycerin patch application: particularly, mean systemic arterial (MAP), right atrial (RAP) and pulmonary wedge pressures (PWP) declined from 96 +/- 10, 8.9 +/- 1.8 and 20.1 +/- 5 to 81 +/- 6, 4.7 +/- 1.5 and 12.2 +/- 3 mmHg (-15.6, -47.2 and -59.3%, respectively); systemic vascular resistance (SVR) and heart rate (HR) were reduced from 1645 +/- 121 to 1288 +/- 89 dyne.s.cm-5 and from 85 +/- 7 to 81 +/- 7 b/min; lastly, cardiac index (CI), stroke volume (SVI) and stroke work index (SWI) increased from 2.3 +/- 0.3, 28.2 +/- 5 and 28.7 +/- 9 to 2.7 +/- 0.3 l/min/m2, 33.3 +/- 5 ml/min/m2 and 31.5 +/- 8 g.m/m2 (+17.4, 18.1 and 9.7%). After 1 month of either continuous or intermittent patch application with 4 hours intervals, hemodynamic parameters returned to control values with no significant change after patch application. In contrast, after intermittent patch application with 6 hours intervals, a persistent hemodynamic response to nitroglycerin patches was still present.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:[The acute, chronic continuous after treatment and chronic intermittent with a variable therapeutic window (4 and 6 hours) hemodynamic effects induced with transdermal nitroglycerin in patients with congestive heart failure]. 176 29

To determine the hemodynamic and clinical effects of long-term positive inotropic stimulation on the myocardium, we treated 31 patients with severe chronic heart failure with oral amrinone (600 mg daily) and performed invasive hemodynamic studies during short- and long-term treatment with the drug. Stroke volume and stroke work indexes increased markedly during the first 48 hr of therapy (p less than .01) but returned to pretreatment values after 2 to 10 weeks; upon drug withdrawal, both variables deteriorated rapidly to values significantly lower than those observed before treatment with amrinone (p less than .01), despite similar values for left ventricular filling pressure, mean arterial pressure, and systemic vascular resistance. This pattern of response indicated that progression of the underlying heart disease had occurred during treatment with amrinone and contributed importantly to its failure to produce long-term benefits. Progression of left ventricular dysfunction was associated with a progressive increase in heart rate and plasma renin activity and a decline in serum sodium concentration. Clinically, amrinone therapy was complicated by sustained symptomatic ventricular tachycardia in four patients, worsening myocardial ischemia in four patients, and worsening congestive heart failure in eight patients, all of whom had been stable before entry into the study; only three of the 31 patients improved clinically. Ten patients died during the first 2 weeks of treatment, and 16 (52%) were dead within 3 months, a mortality rate twice as great as that seen during comparable trials with vasodilating drugs. Although noncardiac adverse effects were frequent, they were not the primary reason for drug failure. In conclusion, long-term therapy with amrinone may accelerate progression of left ventricular dysfunction, exacerbate myocardial ischemia, and provoke life-threatening ventricular tachyarrhythmias, thereby shortening survival in patients with severe chronic heart failure. Prolonged administration of inotropic drugs may achieve short-term gains at the expense of long-term detrimental effects on the myocardium.
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PMID:Hemodynamic and clinical limitations of long-term inotropic therapy with amrinone in patients with severe chronic heart failure. 638 99

The aims of this study were to determine: (1) the proportion of elderly hypertensive subjects currently attending a hospital hypertension clinic suitable for a trial of antihypertensive drug withdrawal, (2) the proportion of suitable patients who can be successfully withdrawn from drug therapy while receiving nonpharmacological advice, and (3) the factors associated with successful withdrawal. One hundred and five consecutive hypertensive subjects, 53% female, mean age 76 years (range 65-84 years) on pharmacological antihypertensive therapy for > 1 year were studied, of whom 78 (74%) had a clinic SBP < 175 mmHg and DBP < 100 mmHg. Subjects with recent myocardial infarction or stroke or with symptoms of ischaemic heart disease were excluded. Antihypertensive drug therapy was withdrawn in this group and nonpharmacological advice to lower BP was instituted. Clinic BP and weight were subsequently recorded monthly for 12 months in all subjects and at every three months in those who had a possible follow-up period of 24 months. The 24h ambulatory BP was measured at baseline and repeated one month off therapy; 24h urine electrolytes were also assessed at baseline and at 12 months or before restarting drug therapy. Seventy-four (70%) subjects had a potential follow-up of 12 months (four were withdrawn from the study) and 64 were available for two years of follow-up. Antihypertensive treatment was restarted if SBP > or = 160 mmHg and/or DBP > or = 90 mmHg on two consecutive visits. After 12 months, 20 (25%) of those withdrawn remained normotensive, the majority restarting therapy did so in the first three months.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Possibilities for antihypertensive drug therapy withdrawal in the elderly. 785 30

Practical feasibility and clinical tolerability of low dose heparin given subcutaneously for the prevention of reinfarction were evaluated in this open, multicentric trial of post-marketing surveillance. 309 investigators participated. 2830 evaluable patients (2090 M, 709 F, mean age 63 years) who had in the previous 2 years a myocardial infarction were treated subcutaneously with calcium heparin (Calciparina Italfarmaco, 0.5 ml prefilled syringe) at the daily dosage of 12.500 U. The foreseen treatment length was of 1 year; after 6 months of daily injections, calcium heparin could be taken for cycles of 30 days, with 10 day intervals. The enrolled patients resulted to be representative of the population affected with ischemic cardiopathy. One year treatment with calcium heparin was completed by 2040 patients (72.1%); about 1/4 of the patients did not complete the protocol. Patient's subjective decision to withdraw accounted for 46.3% of withdrawals; poor tolerability accounted for 15% of withdrawals (3.8% of total patients). Overall, 237 patients (8.4%) suffered from adverse reactions (353 complaints). Local reactions at the injection site accounted for 60% of total adverse reactions, involving 7.5% of total cases. To follow, allergic reactions (2.5%) and other different types of adverse reaction (incidence less than 0.5%). By analyzing the reactions that provoked drug withdrawal, no organ or function (e.g.: haemostasis) were found to be at risk during the heparin treatment. 64 patients died during the trial. These deaths were in prevalence due to cardiovascular diseases: ventricular fibrillation, cardiac failure, arterial thromboembolism (cardiac reinfarction, stroke).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[The feasibility and tolerability of prolonged treatment with low doses of heparin-calcium administered subcutaneously in infarct patients. A multicenter clinical study]. 810 97

We retrospectively reviewed the clinical course of adult patients treated for generalized status epilepticus (SE) at the San Francisco General Hospital (SFGH) from 1980 to 1989. The review was designed to determine whether the etiologies of SE at our hospital have changed over the last two decades, and to investigate the relationships between etiology, response to anticonvulsant therapy, and short-term clinical outcome. Of 154 patients reviewed, the four leading etiologies for SE were anticonvulsant drug withdrawal (39), alcohol-related (39), drug toxicity (14), and CNS infection (12). This pattern was essentially unchanged from observations made at SFGH in the 1970s. Sixty percent of all patients responded to first-line drug treatment (usually phenytoin +/- diazepam), and the remainder required an additional agent (usually phenobarbital) for control of SE. The best response to anticonvulsants occurred in patients with SE related to tumor, anticonvulsant drug withdrawal, or refractory epilepsy, and the poor responders had anoxia, drug toxicity, CNS infection, or other metabolic abnormalities. Seventy-six percent of the patients had good outcomes. Of the 22 patients who died, SE was a likely cause of death in only two (ie, 1.3% of the entire study group). Metabolic abnormalities, stroke, and anoxia were associated with particularly poor outcomes compared with other etiologies. These observations show that the etiologies of SE have remained similar over two successive decades, and that the etiology of SE may help predict both the initial response to drug therapy and the short-term outcome.
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PMID:Status epilepticus at an urban public hospital in the 1980s. 845 Sep 88

The Fifth Report of the Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure recommends that attempts to discontinue antihypertensive drug therapy be considered after blood pressure (BP) has been controlled for 1 year. However, discontinuation of drug therapy could unmask underlying conditions and precipitate clinical cardiovascular events. The Trial of Nonpharmacologic Interventions in the Elderly (TONE) was a clinical trial of the efficacy of weight loss and/or sodium reduction in controlling BP after withdrawal of drug therapy in patients with a BP< 145/85 mm Hg on 1 antihypertensive medication. Of 975 participants, 886 entered the drug withdrawal phase of the trial and 774 were successfully withdrawn from their medications. Thirty-three events (stroke, transient ischemic attack, myocardial infarction, arrhythmia, congestive heart failure, angina, other) occurred between randomization and the onset of drug withdrawal (median time 3.6 months), 57 events occurred either during or after drug withdrawal (14.0 months), and 36 events occurred after resumption of antihypertensive therapy (15.9 months). Event rates per 100 person-years were 5.5, 5.5, and 6.8 for the 3 time periods (p=0.84) in the nonoverweight group and 7.2, 5.2, and 5.6 (p=0.08) in the overweight group. The study shows that antihypertensive medication can be safely withdrawn in older persons without clinical evidence of cardiovascular disease who do not have diastolic pressure > or = 150/90 mm Hg at withdrawal, providing that good BP control can be maintained with nonpharmacologic therapy.
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PMID:Does withdrawal of antihypertensive medication increase the risk of cardiovascular events? Trial of Nonpharmacologic Interventions in the Elderly (TONE) Cooperative Research Group. 987 55

The authors reviewed clinical records of 57 consecutive adults (age: 17-78, 63%--men) treated in the intensive care unit to convulsive SE that was refractory to first-line medication (BDZ,PB). They were divided into three groups: up to 30 (mean 21 years, 28%), between 31-50 (43 y, 32%) and above 50 (59 y, 40%), 58% had previously had epilepsy with prevalence in the youngest (85%). Among the oldest in whom epilepsy occurred de novo as much as 42% experienced it in the form of convulsive SE. Generalized SE was observed in 83% of cases; exclusively in patients up to 50 and in 61% of the oldest. The identifiable precipitating causes of SE were determined in 72% cases but in 25% there were two or more of them. Among previously epileptics leading etiologies for SE were: alcohol abuse, infection or drug withdrawal. Recent brain injury (stroke, neuro-infection, trauma) accelerated refractory seizures in epilepsy-free cases. Time to recovery varied from 0.5-2 (6%) to 2-6 or above 6 hrs (46% each) after continuous i.v. administration of BZD or chlormethiazole (53%) when ineffective. No side effects were noted. The commonest complications during SE were hyperthermia and transient dysregulation of circulatory or/and respiratory systems. Everyone was led out of SE. Overall mortality amounted to 12%. Among the deceased 71% were in the oldest group and everyone with recent brain lesion. This study highlights differences in the course of convulsive SE according to age and underlying etiology and the importance of intense care in therapeutic schedule. A more common chlormethiazole administration, a useful therapeutic tool in management of convulsive SE in adults had been discussed.
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PMID:[Convulsive status epilepticus--clinical analysis of patients treated iin the Neurological Clinics, Medical Academy in Lublin in the years 1986-1995]. 1076 Dec 41

The nonpeptide AT(1) receptor antagonist candesartan is generated from the prodrug candesartan cilexetil during gastrointestinal absorption. In vitro studies have shown that candesartan acts as an insurmountable, tightly bound antagonist at the AT(1) receptor, producing a dose-dependent reduction in the maximal responses to angiotensin II (AII) and virtually an elimination of the AT(1) receptor-mediated effects of AII at high concentrations. The binding of candesartan to the AT(1) receptor is highly selective, and the drug dissociates slowly from the receptor. Candesartan cilexetil produces the expected changes in the parameters of the renin-angiotensin system. Plasma renin activity and plasma AII concentrations were increased and aldosterone levels decreased following drug application. As a consequence, stimulation of AT(2) receptor-mediated actions of AII, such as growth inhibition and vasodilation, may contribute to the overall effects of the AT(1) antagonist, since the AT(2) receptors are left unopposed by candesartan. The antihypertensive efficacy of candesartan cilexetil has been demonstrated in different animal models of hypertension including 2 kidney-1 clip and 1 kidney-1 clip hypertensive rats and spontaneously hypertensive rats (SHR). Candesartan cilexetil produced a slow onset, long-lasting antihypertensive action at a dose range of 0.1-10 mg/kg with no rebound effect upon drug withdrawal. A growing number of studies indicate that candesartan cilexetil can produce end organ protection in addition to lowering blood pressure. In preclinical studies, candesartan cilexetil caused prevention and regression of left ventricular hypertrophy and cardiac fibrosis, protected the heart against ischemia-reperfusion injury and reduced myocardial damage during myocarditis. In different animal models of renal dysfunction, candesartan cilexetil reduced proteinuria and albuminuria, inhibited histopathological renal changes and controlled the renal expression of TGF-beta1 and collagen types I and III. Finally, in stroke prone SHR, candesartan cilexetil markedly attenuated the incidence of stroke even at low doses, with minimal blood pressure lowering effects, and fully protected against stroke at higher doses.
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PMID:Candesartan cilexetil: development and preclinical studies. 1297 13

Seizures often occur in substance abusers. The mechanism may be indirect (CNS infection, cerebral trauma, stroke, metabolic derangement) or direct (intoxication or withdrawal). These mechanisms are not mutually exclusive. A patient with obvious overdose or abstinence symptoms might also have meningitis or an acute subdural hematoma, and a polydrug abuser might be simultaneously intoxicated by one drug while withdrawing from another. Management of such patients often requires much more than simple administration of an anticonvulsant medication. Medical and surgical emergencies must be identified and nonconvulsive signs of intoxication and withdrawal must be addressed. A basic principle in treating drug withdrawal is to use an agent from the same pharmacologic class or one with a degree of cross-tolerance. Long-term anticonvulsant prophylaxis is usually not indicated when drug intoxication or withdrawal is the sole cause of a seizure.
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PMID:Seizures and substance abuse: treatment considerations. 1719 Sep 22


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