Annals of Pharmacotherapy

A practical guide to the drug interactions involving theophylline kinetics is presented. The text is classified into three categories—pharmacokinetics, pharmacodynamics, and miscellaneous drug interactions. In the discussion of pharmacokinetics, interactions are classified according to site; in vitro, intestinal, metabolic, protein binding, and renal mechanisms are considered. The pharmacodynamic section concentrates on possible additive effects of theophylline and other commonly used bronchodilators, while in the miscellaneous section, discussion is devoted to those interactions involving allergic skin testing and changed results of commonly used assay methods for theophylline. Increased awareness of possible interactions should lead to a more critical approach to theophylline prescribing, particularly in those cases where an unexpected therapeutic effect (or theophylline serum concentration) is obtained during the treatment of asthmatic patients.

Studies evaluating the relationship of serum digoxin concentrations (SDCs) with pharmacodynamic effects in atrial fibrillation have important limitations. In general, a poor correlation is found between SDC and ventricular rate, but this is understandable, considering the many other factors that affect conduction through the atrioventricular node.

The ventricular rate, although a clinically important and easily monitored parameter, may not always be a good measure of digoxin effect. In certain patients, signs and symptoms of toxicity may develop before the desired decrease in heart rate. The SDC may provide, in many cases, information that cannot be obtained solely from the clinical response, but is of great relevance to therapeutic decision making.

Nomifensine is an isoquinoline antidepressant that inhibits the reuptake of dopamine at central synapses. It also inhibits norepinephrine reuptake but is only a weak inhibitor of 5-hydroxytryptamine. Open and controlled trials comparing nomifensine with placebo and other standard antidepressants have shown it to be an effective antidepressant in divided doses up to 200 mg/d. The full dosage range of 50–200 mg/d is well tolerated, and doses can be selected to suit patient disease, age, and therapeutic response. Minimal anticholinergic and sedative side effects and no impairment of psychomotor performance make nomifensine a suitable drug for use in a wide variety of ambulatory outpatients, including the elderly. A relative lack of cardiotoxicity and epileptogenic activity add to this profile; the safety of the drug, when taken in overdose, has been documented. However, the place of nomifensine in the treatment of depression, relative to other antidepressants, is still unclear.

Data on patterns of psychotropic drug use from a two-part study of Québec urban women are reported. Part I involved telephone interviews with 1187 women on their use of pain, sleep, and psychotropic medications. In Part II, 179 women participated in a further person-to-person interview. Areas covered included frequency and duration of use, efficacy of the product, dosage, presence of undesirable side effects, source of drug information, and the concomitant use of other medications. Diazepam and flurazepam (Valium and Dalmane) were the most frequently consumed psychotropes, with diazepam second only to aspirin as the most commonly used of all the medications. The majority of psychotropic users obtained the drug initially through a general practitioner for nonspecific health reasons, were satisfied with the efficacy of the drug, took the medication as directed, felt informed of the effects, and found no undesirable side effects. Multiple psychotrope use was not prevalent, and users of mood-modifiers were generally alcohol abstainers. The differences between the high and moderate users, including satisfaction with the psychotropes as well as initial dosages, are discussed along with comparative data from other similar drug studies. Findings lend credence to the hypothesis that the vague and ill-defined health problems precipitating a psychotropic prescription may in fact be economic, social, or psychological in origin.

The author has developed a program for the Hewlett Packard HP 41C calculator that is used in the analysis of aminoglycoside serum levels for the purpose of generating a personalized dosage regimen. Although other programs have been published, until now none has made adjustments in the half-life of drug elimination due to the tissue accumulation that occurs in the initial phases of dosing. Many of these same programs fail to locate the true peak and trough serum levels, which are essential in the calculation of the volume of distribution of the aminoglycosides. This article is not meant as a method of initial dosing, but rather assumes that the physician has chosen one of the readily usable methods of dosing, such as various nomograms.

Patient data taken from published studies were used in generating individual patient parameters. These parameters were compared to those calculated in the studies for means of comparison. While correlation in all parameters was not ideal, the correlation of dose and dosing interval was exact and correlation of predicted peaks and troughs with the given regimen of dosing was excellent.

A compilation of drugs and the histopathological changes that can occur in the liver is presented. The purpose of this review is to provide the reader with a comprehensive and reliable source of information on various drugs that have been documented by liver biopsy to cause hepatocellular damage. The morphologic terms used in the tables have been chosen based on past publications dealing with this subject. This review is intended as a concise guide to aid in the identification of drug-induced liver diseases.

The concept of symptom-avoidance behavior is discussed, with particular reference to home intravenous hyperalimentation (HIVH) patients. Symptom-avoidance behavior is explained as a combination of a health behavior model and an expectancy motivational theory leading to a basic outcome, which is satisfactorily avoiding the onset of symptoms. A systematic behavioral assessment method is presented, based on anecdotal cases; it is experimental in nature and can serve as a guide for practitioners who wish to initiate HIVH.

This two-phase retrospective study was designed to evaluate the impact of the clinical pharmacist on prescribing practice of physicians in an internal medicine service. Streptococcal (pneumococcal) pneumonia was chosen as the model disease state. The drug of choice was used more frequently and there was a statistically significant difference in raw cost of antibiotic, total cost for antibiotic administration, daily raw cost for antibiotics; total raw cost for antibiotic administration, and patient charges when physicians were exposed to the clinical pharmacists' influence.

The purpose of this study was to evaluate a drug history method. The method consisted of a review of systems (ROS) history format, which utilized common symptoms/diseases per organ system matched with corresponding drug treatments. Findings of this method were compared with drug histories documented in the medical record. The study was conducted over an eight-week period on general medicine inpatients and ICU patients. All data retrieved were categorized into total number of drugs found and then analyzed as to legend, non-legend, and unidentifiable content. Findings were statistically analyzed using chi–square. During the study, 207 patients were admitted. Of these patients, 186 drug histories were obtained; 21 patients could not be interviewed. The ROS method documented 406 drugs as compared with 60 drugs by the medical record (p < 0.001). Performance time was comparable to similar studies (14 ± 5.85 min). Using a concise, logically organized technique, more drugs were identified than reported by the medical record. We conclude that the experimental method is a productive method for obtaining a drug history.

Many health profession educators do not use computerized test grading and analysis to help them improve their courses and testing nor to assess objectively student performance and competency. The main thrust of this article is the listing of advantages and disadvantages involved in incorporating computerized test grading and analysis in the hope that more instructors will realize and pursue this as an additional effective means of accomplishing course goals and instructional objectives.

A case that utilizes a pharmacokinetic approach to evaluate the need for withdrawal prophylaxis after a phenobarbital overdose is presented. To date, the practitioner has had to rely on an accurate drug-use history to predict which patients may be at risk for withdrawal symptoms. Since this information is often difficult to obtain, some other means of identifying potential withdrawal-syndrome patients would be useful. This case describes the successful use of kinetically determined parameters, the elimination rate constant and half-life, in predicting withdrawal potential. This easily used kinetic approach may provide practitioners with a useful tool for predicting those patients at risk for withdrawal symptoms following phenobarbital overdose.

Two patients who presented with unusual cutaneous reactions attributed to quinidine are described. One had a diffuse nonpruritic macular rash, and the other had a localized pruritis without cutaneous manifestations. Both resolved upon de-challenge with quinidine. Disopyramide phosphate was substituted for quinidine in both cases, without subsequent problems.

The authors report two cases of anaphylactic reaction to zomepirac. A brief discussion of anaphylactic reactions to other nonsteroidal antiinflammatory agents, for example, tolmetin and sulindac, is included. The authors note that first exposure to the NSAIDs usually produces few, if any, adverse effects in patients who later suffer severe reactions.

We reviewed reactions previously reported in patients treated with isoniazid, who ate certain fish and cheeses. We observed similar reactions in two patients after they ingested cheese and wine. Isoniazid is an inhibitor of both monoamine and diamine oxidases, which contribute to the metabolism of histamine that may be present in some fish and cheeses. Monoamine oxidase also acts in the metabolism of tyramine, present in some cheeses and wines. Reactions reported after eating fish or cheese, in patients treated with isoniazid, are similar in that both are characterized by headache, palpitations, skin flushing, nausea, vomiting, and pruritus. Reactions after fish have not been associated with increased blood pressure, whereas those following cheese ingestion frequently result in modest increases in blood pressure. Patients treated with isoniazid should be alerted to the possibility of reactions after eating certain foods.