Optimizing pharmacologic therapy for the elderly

The authors analyze the most important aspects one should bear in mind regarding medication in elderly patients. The authors study the pharmaco-kinetic and pharmaco-dynamic changes which occur with aging and how these influence variations in therapeutic responses and their most frequent adverse reactions among the elderly. The authors conclude that it is necessary to draw up individualized therapeutic plans for these patients. The authors also analyze the general recommendations made for administering and prescribing medications for the elderly. Considering that the administration of medication and the evaluation of adverse reactions are some of the most important responsibilities nurses have, the authors recommend specific programs be drawn up to evaluate the efficiency-risk binomial and to keep a close watch on adverse reactions in these patients.     

Kinetics and metabolism of carbamazepine during combined antiepileptic drug therapy.

The kinetics of carbamazepine using 15N-carbamazepine were investigated in epileptic patients during combined anticonvulsant therapy. The 15N-carbamazepine plasma half-lives ranged from 5.0 to 13.6 hr with a mean of 8.2 hr. These half-lives are appreciably shorter than reported during chronic carbamazepine monotherapy. Predicted steady-state plasma levels and observed plasma levels of carbamazepine were in excellent agreement. Between 32% and 61% of the dose administered is excreted in the urine as carbamazepine-trans-diol, 5.2% to 8.8% as 9-hydroxymethyl-10-carbamoyl acridane, 1% to 1.4% as 10,-11-carbamazepine epoxide, and 0.5% as carbamazepine. The data indicate that it is the epoxide-diol pathway which is induced during long-term treatment. Concomitant therapy with primidone, phenytoin, phenobarbital, ethosuximide, or methsuximide further induces carbamazepine metabolism.     

Discontinuing antiepileptic therapy

Prognosis for successful withdrawal of antiepileptics is excellent in selected patients. Studies indicate that therapy should be maintained for at least three seizure-free years before antiepileptics are discontinued. The decision to withdraw medication in an epileptic patient hinges on the likelihood of seizure recurrence and a critical assessment of the benefits of discontinuing therapy as compared with the possible consequences of a recurrent seizure.     

Pharmacology and drug therapy in critically ill elderly patients.

Aging is a complex, normal, and inevitable process affecting all living things. The physiologic changes of aging, by definition, are postmaturational, occurring after adult maturity is achieved. Changes with aging are primary, irreversible, and progressive. While the processes of aging are neither pathology nor disease, they present important changes in structure and function that alter drug disposition, metabolic rate, and excretion. These changes present special challenges to clinicians in critical care settings for whom pharmacotherapy is a common treatment modality. This article explores the physiologic changes associated with aging and the implications of these changes for management of critically compromised elders. Drug metabolism, distribution, utilization, and excretion in older adults are examined.     

Optimizing reserve in hospitalized elderly

Aging is a multidimensional process that involves the physical, psychosocial, and spiritual domains. The reserves in each of these areas are challenged during the stressful experience of acute and critical care illness and hospitalization. It is imperative that hospital nursing staff recognize the vulnerability of the elderly and take appropriate evidence-based interventions to prevent avoidable decline and deterioration. There are opportunities for nurses to strengthen reserve in the elderly in the areas of practice, research, education, and policy.     

Growth hormone therapy in elderly people: an age-delaying drug?

Summary— The aims of this review are to present a brief overview of growth hormone (GH) physiology and to summarize the studies of GH treatment in adults. Special attention has been paid to randomized controlled trials. Studies have revealed a partial deficiency of GH secretion in the elderly. GH secretion on the average declines by 14% with each decade in normal adults after 20 years of age. Aging has a central effect on the GH secretion and peripheric effect on insulin-like growth factor 1 (IGF-1) through changes in the body composition. GH administration may attenuate several important decrements in body composition and in function associated with aging. GH may also have very potent anabolic effects in surgical situations. Short-term side-effects of GH therapy include edema, carpal tunnel syndrome and arthralgia. A number of agents such as oral GH-releasing peptides (GHRPs) increase GH secretion; they may be an alternative to GH treatment in the future. Further studies of GH replacement are needed, examining issues such as dosage, tolerance and efficacy before the widespread use of GH in the elderly is advocated.     

Rational use of antiepileptic drug levels.

Antiepileptic drug (AED) levels are obtained frequently in clinical practice, but their complex relation to seizures or drug toxicity often makes interpretation of the results difficult. Research studies have not always taken into account clinical, as well as pharmacokinetic and pharmacodynamic, factors which may influence the drug level-effect relationship. AED levels should be drawn at an appropriate time in relation to drug ingestion and clinical symptoms. Systematic investigations in selected patients, during which several levels are obtained, may be more rewarding than routine measurements in a large clinic population.     

育龄妇女抗癫痫药的合理使用

育龄妇女的抗癫痫治疗对临床医生是一个挑战,必须考虑很多问题。癫痫女性(WWE)怀孕期间终止甚或改变抗癫痫药(AEDs)方案很危险,可能导致母亲和胎儿的损害或死亡;少数情况下,中断AEDs似乎合理,但多数在孕期需要继续使用AEDs。怀孕期间AEDs的代谢可能发生很大变化,对WWE后代的风险包括特定AED的不良反应风险以及癫痫发作本身的风险,很多AEDs有众所周知的致畸作用,还有产科并发症、新生儿预后不良、先天性畸形,甚至对孩子随后的认知功能有风险。必须告知其相关风险,适当地指导其治疗,孕前优化癫痫治疗、选择最有效的AEDs以控制癫痫,尽可能用单药治疗且用最小有效量,避免多药治疗和丙戊酸,补充叶酸,最大限度地控制癫痫发作并降低风险。     

Clinically significant pharmacokinetic drug interactions between antiepileptic drugs

Pharmacokinetic interactions between antiepileptics represent a major potential complication of epilepsy treatment because drug combinations are common. This review discusses pharmacokinetic drug interactions of clinical significance involving antiepileptics and cytochrome P450 (CYP). Most commonly used antiepileptics are eliminated through hepatic metabolism, catalysed by the enzymes CYP2C9, CYP2C19 and CYP3A4 and uridine diphosphate glucuronosyltransferase (UDGPT). Antiepileptics are associated with a wide range of drug interactions, including hepatic enzyme induction and inhibition. Phenytoin, phenobarbiral, primidone and carbamazepine induce CYP and UDPGT enzymes while valproic acid inhibits them. Avoidance of unnecessary polypharmacy, selection of alternative agents with lower interaction potential and careful dosage adjustments based on serum drug concentration monitoring and clinical observation are the main methods for reducing the risks associated with these interactions.