Drug interactions with the nonsedating antihistamines

The nonsedating antihistamines are frequently prescribed agents. Well-documented drug-drug interactions with two of these agents, terfenadine and astemizole, may result in serious adverse effects, including death, when they are prescribed along with macrolide antibiotics and/or the antifungal agents itraconazole or ketoconazole. Fexofenadine and loratadine appear to be the least likely nonsedating antihistamines to interact with other medications and to result in a life-threatening interaction. This article reviews the known drug-drug interactions involving nonsedating antihistamines and provides a basis from which the clinician can predict potential interactions.     

Drug-drug interactions in pediatric psychopharmacology

Serious consequences caused by drug-drug interactions continue to plague contemporary pharmacotherapy. The possibility of a drug-drug interaction should be suspected anytime a new or unexpected effect occurs that complicates the clinical management of a patient in the setting where the patient is receiving more than one drug. In this article, the authors address the mechanisms of pharmacokinetic-based drug-drug interactions focusing on important interactions that may occur with the common medications a pediatrician may prescribe to the child receiving psychoactive medication(s) prescribed by a child psychiatrist.     

Body adaptation to the action of ecological factors at the cellular and subcellular levels

While poor drug compliance is a significant impediment to the effective treatment of hypertension, knowledge of what patients wish to know about their medications in order to improve compliance is very limited. To develop a preliminary understanding of patients' medication requirements and expectations, a simple 30-item questionnaire was developed and administered to 66 patients who were either taking antihypertensive drugs, or about to commence antihypertensive drug treatment. Ninety percent of patients wanted to know about all possible side effects of medications as well as the most likely side effects. Ninety-six percent wanted to know if their drug treatment would keep them well. In addition, most patients wanted to avoid multiple medications, were concerned about the prospect of life-long treatment, and were worried about potential drug interactions. Effects of the drugs on their lifestyles as well as any lifestyle changes required to augment drug therapy were other issues of concern. The elderly were less interested in many of these issues. A strong desire for further knowledge about their disease was noted in most subjects (82%). If compliance with medication therapy is to be improved, a better understanding of patients' concerns and fears about medications is required, particularly in a relatively asymptomatic disease like hypertension.     

Effects of kappa-opioid receptor stimulation in the heart and the involvement of protein kinase C

Agitation in the elderly, manifested by verbal and physical aggression, frequently results in increased morbidity and mortality for nursing home residents and reduced morale for the family and nursing home staff. It is also responsible for increased costs associated with caring for these residents. Pharmacologic interventions are often used but are frequently ineffective and associated with significant adverse effects. Few controlled studies of drug treatment are available, but divalproex sodium and carbamazepine are effective and well tolerated by this population. Divalproex sodium has advantages of fewer adverse side effects and drug-drug interactions.     

Special characteristics of psychopharmacotherapy of elderly patients

While mental disorders in the elderly can often be treated by non-medical means, suicidal ideation or agitation may require the use of psychotropic agents. Since pharmacokinetics and pharmacodynamics change with increasing age of the patient, there are a number of particular features of the use of psychotropic drugs in the elderly that urgently need to be taken into account. Geriatric patients usually require only about one-half the dose needed by younger patients, and not only the side effects of psychotropic drug treatment but also, and in particular, possible interactions with other medications must also receive appropriate consideration.     

Friendships, peer acceptance, and group membership: relations to academic achievement in middle school

Polypharmacy is commonly encountered in human immunodeficiency virus (HIV)-positive patients, and the risk and frequency of drug-drug interactions are significant in this patient population. Most HIV-positive patients receive the antiretroviral drug zidovudine (3'-azido-3'-deoxythymidine, ZDV), the first drug to be approved for the treatment of HIV. Many drug interactions with ZDV have already been reported. As HIV pharmacotherapy becomes more complex, the potential for drug-drug interactions is likely to increase significantly.     

Frequency of hospitalization after exposure to known drug-drug interactions in a Medicaid population

A matched-pair case-control analysis of Medicaid claims was performed to determine the risks of hospitalization associated with drug-drug interactions. Patients were hospitalized and controls were not. They were randomly matched based on contemporaneous eligibility for Medicaid benefits. Odds ratios for hospitalization in patients exposed to known drug-drug interactions were compared with those in patients exposed to one of the interacting agents. When confidence intervals did not overlap, the odds ratio was considered to be significantly increased. Odds ratios were significantly increased for many interacting drug pairs, and were associated with commonly recognized interactions as well as less widely recognized ones. Cimetidine interactions achieved significance only with theophylline. In the Medicaid population, exposure to a number of drug-drug interactions was associated with a significantly increased risk of hospitalization.     

Drugs and the elderly.

The elderly person is 2–5 times more likely to experience an adverse drug reaction than a younger adult. Increased incidence of chronic disease and age-related biologic and physiologic changes may lead to altered pharmacokinetics. Socioeconomic and psychologic factors may interfere with ability to obtain and to comply with a medication regimen. Multiplicity of health problems may lead to polypharmacy, increasing the risk of drug–drug interactions. Health professionals must be ever vigilant to the risks and hazards of medication therapy in elderly patients. A change in mental status is often the first indicator of an adverse drug reaction. A thorough medication history, education about medications, and simplification of medication regimens are the best means of reducing the frequency of adverse drug reactions in the elderly. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Antiparkinsonian agents. Drug interactions of clinical significance

Within the past 3 decades revolutionary changes have taken place in the pharmacological management of Parkinson's disease. Used alone, or often in combination, antiparkinsonian agents can dramatically and meaningfully ameliorate the symptoms of Parkinson's disease. However, with the development of effective therapeutic agents has come the potential for drug interactions; these interactions can produce consequences that range from the inconsequential to incapacitating and even life-threatening. Drug-drug interactions are not a major problem with either the anticholinergic medications or amantadine. However, cumulative anticholinergic toxicity may occur when multiple drugs with anticholinergic properties are utilised concomitantly, and amantadine toxicity can be triggered by drugs that impair its renal clearance. Gastric emptying and levodopa absorption can be significantly altered by medications and dietary contents. A rather extensive array of medications can interfere with dopaminergic function and thus produce clinical parkinsonism or impair the effectiveness of levodopa. The effectiveness of direct dopamine agonists can also be affected by a small group of agents. As a selective monoamine oxidase type B (MAO-B) inhibitor, selegiline (deprenyl) is free of the 'cheese-effect' when employed in recommended dosages. However, potentially life-threatening drug interactions, with both pethidine (meperidine) and with fluoxetine and other antidepressant medications, have been described, presumably occurring via serotonergic mechanisms. Awareness of the potential for drug interactions with antiparkinsonian agents, and prompt recognition of them when they do occur, is vital for the optimum clinical management of Parkinson's disease.     

Regulation of aquaporin-2 gene transcription by GATA-3. off

Many nursing home residents are candidates for antipsychotic pharmacotherapy for dementia-related behavioral disturbances that include physical agitation and aggression, verbal outbursts, anxiety, and depression. These patients are often resistant to or intolerant of standard neuroleptics and are usually receiving multiple medications for concurrent psychiatric or medical conditions. New medications must be carefully considered because they may interact with concurrent medications or aggravate concurrent medical problems. Low doses of risperidone may be better tolerated in the elderly because the drug poses little risk of extrapyramidal side effects or blood disorders. One hundred and nine patients with dementia-related behavioral disturbances were studied in 9 nursing homes; most initially received 0.25 to 0.5 mg of risperidone twice daily. Their behavior was recorded for up to 6 months on questionnaires completed by a nursing staff member at each home. Risperidone was well tolerated overall and nursing staff viewed it as helpful in 38 of 100 patients, moderately helpful in 26, slightly helpful in 17, and not helpful in 19.     

New medical therapies in glaucoma management

New and potent medications such as alpha 2-adrenergic agonists, topically active carbonic anhydrase inhibitors, and prostaglandin analogs, are now available for use in the treatment of glaucoma. These ophthalmic medications have the potential to cause serious drug interactions and systemic side effects. The primary care physician should be able to recognize and to monitor any potential adverse effects and interact with the prescribing ophthalmologist for optimal patient care.     

Drug-induced disorders

Recent estimates suggest that each year more than 1 million patients are injured while in the hospital and approximately 180,000 die because of these injuries. Furthermore, drug-related morbidity and mortality are common and are estimated to cost more than $136 billion a year. The most common type of drug-induced disorder is dose-dependent and predictable. Many adverse drug events occur as a result of drug-drug, drug-disease or drug-food interactions and, therefore, are preventable. Clinicians' awareness of the agents that commonly cause drug-induced disorders and recognition of compromised organ function can significantly decrease the likelihood that an adverse event will occur. Patient assessment should include a thorough medication history, including an analysis of all prescribed and over-the-counter medications, vitamins, herbs and "health-food" products to identify drug-induced problems and potentially reversible conditions. An increased awareness among clinicians of drug-induced disorders should maximize their recognition and minimize their incidence.     

Medications and nutrition in the elderly

Single drug and drug combinations taken by elderly individuals may impose nutritional risk. Nutritional risk induced by drug intake include anorexia, excessive increase in appetite, drug-induced nutritional deficiencies, and toxic reactions. Drug side effects, such as postural hypotension, may interfere with food shopping or cooking ability. Prescribed diets may also impose a risk of drug-induced side effects or diminished drug efficacy. Unwanted outcomes of drug-food and drug-nutrient interactions can be minimized by instructing elderly men and women and their caregivers to avoid timing errors in drug-taking behavior and toxic reactions due to food incompatibility. In addition, drug-induced nutritional deficiencies can be avoided by advising drug-taking elderly on the appropriate levels of nutrient intake.     

Structure, chromosomal localisation and expression of the murine dominant negative helix-loop-helix Id4 gene

In the elderly patients a greater loss of teeth is frequently seen in combination with periodontal diseases. This article presents an overview of the changes of oral structures during ageing as well as immunology, physical and psychological aspects. Also summarised are complications by systemic illnesses, drug medications and periodontal alterations. If possible illnesses and medications are taken into consideration, there should be no special problem for the elderly patients.     

Establishing pharmaceutical care services in an HIV clinic

OBJECTIVE: To present a brief overview of human immunodeficiency virus (HIV) infection and to describe the implementation of pharmaceutical care services for adult patients with HIV infection. SETTING: University hospital clinic. PRACTICE DESCRIPTION: A pharmacist joined a multidisciplinary team serving HIV-infected patients in January 1994. PRACTICE INNOVATION: Current pharmacy services include taking medication histories, educating patients, counseling patients on compliance, monitoring response to therapy, identifying drug-related problems, documenting all interventions, and making therapeutic decisions and formulary choices. The pharmacist also participates in research. INTERVENTIONS: The pharmacist sees patients immediately after their physician appointments. Patients with one or more of the following characteristics are targeted to receive pharmaceutical care: multiple drugs, history of noncompliance, initiation of new drug therapy, recently discharged from hospital or emergency department, identification of potential adverse effects, identification of potential drug-drug interactions, and presence of drug toxicities. CONCLUSION: Pharmacists are uniquely qualified to provide a wide range of pharmaceutical care services to HIV-positive patients. Pharmacy interventions should lead to improved outcomes and decreased costs for a chronic and very expensive disease.     

Pharmacologic treatment of depression in late life

A number of age-related factors, including changes in pharmacokinetics and pharmacodynamics, medical comorbidity and an increased risk of drug-drug interaction, can complicate the pharmacologic management of depression in late life. Nevertheless, over 80% of elderly depressed patients will eventually respond to vigorous treatment and, when treated over 2 years, up to 75% of those will not have a relapse or recurrence of depression. This article reviews a number of issues relating to the pharmacotherapy of depression in elderly people. In particular, it discusses the similarities and differences between various antidepressant medications, issues pertaining to dosing and length of treatment, and management of the patient who does not respond to first-line treatment. The author emphasizes that, because of the high risk of relapse and recurrence, a long-term collaboration between the patient and the physician is required to successfully manage depression in late life.     

Streptogramins and their potential role in geriatric medicine

Despite advances in antimicrobial chemotherapy over recent decades, morbidity and mortality secondary to infection continues to rise. In addition, the incidence of infection caused by resistant organisms has also increased. Concurrently, the elderly are living longer than prior generations, often with disabling chronic diseases. The more debilitated of the geriatric population are at greater risk for infection, and more likely to acquire or develop antimicrobial resistant organisms. Gram-positive organisms are a source of resistance and commonly cause infection in older patients. Whereas resistance is a concern in all patients, in the elderly this is magnified by limitations in treatment options because of differences in pharmacokinetics and tolerance as compared with younger counterparts. Pharmacokinetic differences include changes in drug distribution and may arise as a result of diminished end organ function. Age-related decreases in renal function often impact on commonly prescribed antimicrobials. In addition, the elderly are more susceptible to drug-drug interactions because polypharmacy is common in this patient population. Streptogramins may offer a useful alternative in the treatment of infections in the elderly due to their coverage of organisms commonly causing infections in this population and because of their favourable pharmacokinetic profiles. While published experience is limited, streptogramins are not appreciably eliminated by the kidney and, therefore, they are less subject to age-related changes in renal elimination. What is required is multi-dose pharmacokinetic analysis of streptogramins in geriatric populations and subset analysis of patient use data on file. The following will provide the reader with the most recently presented data on streptogramin use and their potential. While focusing on potential use in the elderly, we have cited data and issues which we believe will be relevant in the geriatric population.