Physostigmine should be used more readily for antimuscarinic toxicity: PRO

Physostigmine is the preferred treatment for antimuscarinic toxicity. Its use has a clear biological rationale and is supported by extensive clinical use which demonstrated effectiveness and safety.

Pheniramine dependence in obsessive-compulsive disorder: A case report

BACKGROUND

Pheniramine abuse is reported not only in patients with psychiatric disorders but also in the general population.

CASE REPORT

We report a case of pheniramine dependence in a patient with obsessive-compulsive disorder. The patient took about 250 mg orally daily and injected about 90 mg every week from the last six months. It reduced his anxiety, was cheaper than his other psychiatric medications, and free of stigma. He had lethargy, headache, uneasiness, anxiety, and poor sleep as withdrawal symptoms.

RESULTS

This case highlights the vulnerability of those with psychiatric disorders towards pheniramine abuse. Hence, this report advocates the strict evaluation of over-the-counter drugs for patients with pre-existing psychiatric disorders.

Nonprescription drug abuse

Nonprescription drug, also referred to as over-the-counter (OTC) abuse, is a serious and growing global health challenge. Drugs from many different therapeutic classes and numerous dosage forms and drug delivery systems are implicated in nonprescription drug abuse. Individuals who commonly abuse certain nonprescription medications are likewise diverse, varying in age, demographics, and overall health status. The clinician is in a unique position to assist in identifying those patients at risk for nonprescription drug abuse and those who are abusers, and may play an important role in intervention, patient care, and in the treatment of nonprescription drug abuse. A concise review of nonprescription drug abuse may be of use to the clinician in this regard.

Toxicologists in public health--Following the path of Louis Roche (based on the Louis Roche lecture "An accidental toxicologist in public health", Bordeaux, 2010)

BACKGROUND

The global burden of clinical toxicology suggests a natural partnership with public health. This article reflects the content of a Louis Roche lecture given in 2010. HISTORICAL CONTEXT: Our practice and research in clinical toxicology has evolved from clinical cases to toxico-epidemiology to public health. This evolution in practice was initially unplanned but gained momentum and impact as we placed it more formally in a public health framework. This perspective is implicit in Louis Roche's call to "examine all aspects of the poisoning problem" and still provides a valuable starting point for any clinical toxicologist.

DISCUSSION

Clinical toxicology has always had a patient centered focus but its greatest successes have been related to public health interventions. Our early failures and later success in pubic health toxicology correlated with our understanding of the importance of partnerships outside our field. The most rapid dissemination and implementation of information derived from research occur through apriori partnerships with other agencies and international partners.

CONCLUSION

Addressing both local and global need has a number of bilateral synergies. Repositioning clinical toxicology into a public health framework increases access to strategic partnerships, research funds, and policy implementation while still addressing questions that are important to clinical practice.

The misuse/abuse of antihistamine antiemetic medication (cyclizine) by cancer patients

Cyclizine is an antihistamine, which is frequently used to manage nausea and vomiting in cancer patients. Antihistamines can be drugs of misuse/abuse, and the article describes four cancer patients who developed such problems after receiving parenteral cyclizine within the inpatient unit of a cancer centre. The article also briefly reviews the literature on the misuse/abuse of cyclizine and other antihistamines.

A case of pheniramine dependence

Abuse and addiction of histaminergic agonists and antagonists were investigated. The withdrawal signs may become after using drugs such as L-histidine, histamine-N-methyl, promethazine, pheniramine, astemizole, etc. Some medicines which include these active metabolites could lead to dependence cause different side effects. This case suggests that pheniramine abuse also could to dependence. We should pay attention to trend of pheniramine and other histaminergic drugs dependence and need to regulate the market by law more severely.

Psychiatric co-morbidity associated with pheniramine abuse and dependence

The abuse of cough syrups containing antihistamines and codeine is being increasingly noted. The abuse of antihistamines alone has also been reported. The use of antihistamines alone or in combination with other substances of abuse may predispose individuals to develop psychiatric symptoms or syndromes as a part of intoxication, withdrawal or as co-morbid conditions. We present two case reports to highlight the occurrence of co-morbid psychopathology in association with antihistamine abuse and dependence.

Case I used high doses of pheniramine for about 2 years and became suspicious of his wife; he even doubted the paternity of his yet-to-be-born child. The associated behavioural abnormalities suggested that he was acting out on the delusion. He also had seizures associated with the intake of a high dose of pheniramine. Case II had multiple substance use, and dependence on alcohol and pheniramine. He demonstrated abnormal behaviour suggestive of psychosis and organic brain syndrome that persisted for a few days and remitted on discontinuation of the substances. These two cases demonstrate the occurrence of psychotic syndromes associated with heavy pheniramine use. The psychopathology can vary from an independent psychotic syndrome to an organic brain syndrome-like disorder.

Data collection in clinical toxicology: are there too many variables?

The evidence base of clinical toxicology suffers in comparison to other clinical disciplines. There is an excess of case reports and case series with little in the way of case control or cohort studies, and very few randomized controlled trials. While randomized controlled trials are rightly regarded as the gold standard for interventional studies, they have limitations that are particularly evident in the practice of clinical toxicology. Properly conducted observational studies using quantitative, epidemiological methods [nonrandomized trials, cohort studies (prospective and retrospective), case control methods] can provide answers that may be impossible to obtain from randomized controlled trials. Development of a strong evidence base is essential for progress in clinical toxicology. Whether that evidence base is derived from randomized controlled trials or observational studies, it is essential to collect data. Important observations can be made from basic clinical data and systematic collection of those data into some form of electronic database has siginificant advantages. A clinical database provides accurate information in the areas of clinical practice, quality assurance (audit), and research. In the area of research, an appropriately designed database can be both a source of hypotheses as well as a vehicle to test them. It can also serve as a repository of research data in subsequent randomized controlled trials.

Alternative ways of using and abusing drugs and complicity of doctors

Many drugs that have been prescribed by doctors are not taken as directed. Altered dose, frequency and route of administration may lead to misuse of drugs that have been prescribed in good faith. Awareness of the abuse potential of prescribed and over-the-counter drugs is the first point of intervention, followed by monitoring of each doctor's practice.

Flashback and nightmares after surgery under neuraxial anesthesia: a report of two cases

Recall, awareness, flashback, and nightmares are reported complications of general anesthesia, but flashback and nightmares after regional anesthesia have not been described. Two patients underwent vascular and orthopedic surgery under spinal and epidural anesthesia, respectively. Local anesthetic consisted of bupivacaine, and sedation was achieved with the combination of fentanyl, midazolam, and diphenhydramine. In both patients the anesthetic course was uneventful, but the recovery process was complicated by flashbacks and nightmares leading to depression, physical complaints, and lengthy convalescence. Flashback and nightmares after neuraxial anesthesia are unreported and, therefore, their incidence is unknown.

Poisoning and epidemiology: 'toxicoepidemiology'

1. There is little hypothesis-testing clinical research performed in toxicology. Randomized clinical trials are rare and most observational studies are performed on highly selected patients and are subject to marked bias. Thus, for many poisonings, our approach has been based almost entirely on deduction from known pharmacological/toxicological effects, generalizations from drugs within the same therapeutic class, animal data and case reports. This is also far from satisfactory, as many toxicological mechanisms are poorly understood and not related to the therapeutic class. 2. Although we need much better data to address the clinical and public health aspects of poisoning, there are many practical and ethical reasons why randomized clinical trials are difficult in this field. However, the scope for observational research, in particular population-based clinical epidemiology, is almost unlimited. The collection of data on human poisoning is facilitated because most non-fatal overdoses are admitted to hospital and by legal requirements to report to the coroner deaths that are due to poisoning. In the present article I argue that 'toxicoepidemiology', meaning the application of epidemiological methods to the problem of acute poisoning, is the best means we have of addressing deficiencies in our knowledge of poisoning. 3. Examples are given of a variety of observational research strategies, ranging from audit to meta-analysis, that may be applied to clinical toxicology. From coronial and clinical data obtained from reasonably well-defined populations, it has been possible to identify a number of previously unrecognized differences in the severity and spectrum of toxicity between and within drug classes. Also, the demographic risk factors for poisoning and the reproducibility, validity and optimal use of diagnostic and therapeutic interventions can be assessed. 4. The major limitations to the range of associations and interventions that may be studied are the need to achieve adequate power to study uncommon outcomes or poisonings and the ability to replicate findings at other centres using similar methodology. The expansion of data collection to other centres has the potential largely to overcome these obstacles.

Self-poisoning in Newcastle, 1987-1992

OBJECTIVE

To examine the morbidity and mortality associated with self-poisoning with different drug classes.

DESIGN

Prospective cohort study with limited follow-up. Retrospective analysis of coronial data.

SETTING

Primary and tertiary referral toxicology centre covering Newcastle and Lake Macquarie, Australia, 1987-1992.

RESULTS

There were 1969 admissions after ingestion of 3724 substances (2424 prescription drugs and 1300 non-prescription items). The coroner investigated 83 drug-related deaths. Only 12 of these people presented to hospital and, for most of these, death was inevitable at presentation. The most frequently ingested substances were benzodiazepines, alcohol, paracetamol, antidepressants, neuroleptics and anticonvulsants. Since 1980, the percentage of self-poisonings involving benzodiazepines has fallen, while it has risen for those involving antidepressants. Over 50% of deaths were due to tricyclic antidepressants or opioid analgesics.

CONCLUSIONS

As death usually occurs out of hospital, interventions to decrease mortality from self-poisoning must focus on prevention, and targeting drugs that are frequently taken or frequently lethal in overdose. Consideration should be given to the use of antidepressants that are safer in overdose. The use of antidepressants, barbiturates or chloral hydrate as sedatives should be discouraged.