Salicylate intoxication in the elderly. Recognition and recommendations on how to prevent it

Lithium Cholesterol Sulfate: A Novel and Potential Drug for Treating Alzheimer's Disease and Autism Spectrum Disorder

BACKGROUND AND OBJECTIVE

Recent studies have shown that lithium treatment can reduce symptoms of Alzheimer's disease (AD) and Autism Spectrum Disorder (ASD). However, the present lithium salts clinically available have serious short-term and long-term side effects which requires frequent monitoring of blood chemistry and plasma lithium levels so as to avoid toxicity. Consequently, there is a demand for a safer and more effective lithium formulation to treat these diseases.

METHODS

Hence, we firstly synthesized lithium cholesterol sulfate (LiCS) and compared its pharmacological effects with that of lithium chloride (LiCl) and sodium cholesterol sulfate (NaCS) on markers of neurodegenerative disease in cell cultures.

RESULTS

LiCS was more potent than LiCl in increasing inhibitory GSK3β (Ser9) phosphorylation (pGSK3β) in both CHO and SH-SY5Y cells. These agents dose-dependently increased pGSK3β, starting at 10 µM for LiCS and 60µM for LiCl and maximally by approximately 100% at 60 µM for LiCS and 1.25 mM for LiCl, without altering total GSK3β levels. In HEK293/tau cells, LiCS reduced tau (Thr231) phosphorylation (ptau) starting at 10 µM and maximally by 63% at 40 µM without altering total tau levels, but ptau levels were not altered by LiCl at any dose between 60 µM and 1.25 mM. In BV2 cells, LiCS and LiCl decreased LPS-induced TNFα levels, starting at 20 µM for LiCS and 5 mM for LiCl, and maximally by approximately 30% at 80 µM for LiCS and 20 mM for LiCl. NaCS at any dose between 5 and 90 µM did not alter pGSK3β, ptau or LPS-induced TNFα.

CONCLUSION

LiCS may become a new drug with good pharmacological potential for the treatment of neurodegenerative disorders such as AD and ASD by allowing lithium to more readily access intracellular pathological processes.

Activated Charcoal and Bicarbonate for Aspirin Toxicity: a Retrospective Series

INTRODUCTION

Aspirin overdose causes acid-base disturbances and organ dysfunction. Management is guided by research reported over 50 years ago when chronic aspirin toxicity was common and accounted for significant morbidity. We investigate our experience of aspirin overdose and the effectiveness of charcoal and bicarbonate administration over 20 years.

METHODS

This is a retrospective series of acute aspirin overdose from two toxicology units from January 2000 to September 2019. Acute aspirin ingestions > 3000 mg were identified in each unit's database. Excluded were cases of chronic exposure, hospital presentation > 24 hours after ingestion, and cases without a salicylate concentration. Included in our analysis was demographic data, clinical effects, investigations, complications, and treatment.

RESULTS

There were 132 presentations in 108 patients (79 females (73%)). The median age was 28 years (range: 13-93 years). The median dose ingested was 7750 mg (IQR: 6000-14,400 mg). There were 44 aspirin-only ingestions. Mild toxicity (nausea, vomiting, tinnitus or hyperventilation) occurred in 22 with a median dose of 160 mg/kg. Moderate toxicity (acid-base disturbance, confusion) occurred in 16 with a median ingested dose of 297 mg/kg. There were no cases of severe toxicity (coma or seizures) due to aspirin alone. The median peak salicylate concentration was 276 mg/L (IQR: 175-400 mg/L, range: 14-814 mg/L). There was a moderate association between dose ingested and peak concentration (Pearson r = 0.58; 95% CI 0.45-0.68). Activated charcoal was administered in 36 (27%) cases, which decreased the median peak salicylate concentration (34.2 to 24.8 mg/L/g (difference: 9.4, 95% CI: 1.0-13.1)). Bicarbonate was administered in 34 (26%) presentations, decreasing the median apparent elimination half-life from 13.4 to 9.3 h (difference: 4.2 h, 95% CI: 1.0-6.5 h).

CONCLUSIONS

Acute aspirin overdose caused only mild to moderate effects in this series. Early administration of activated charcoal decreased absorption and use of bicarbonate enhanced elimination.

Rhabdomyolysis among hospitalized patients for salicylate intoxication in the United States: Nationwide inpatient sample 2003-2014

Introduction

This study aimed to assess the risk factors and impact of rhabdomyolysis on treatments, outcomes, and resource utilization in hospitalized patients for salicylate intoxication in the United States.

Materials and methods

The National Inpatient Sample was utilized to identify hospitalized patients with a primary diagnosis of salicylate intoxication from 2003–2014. Rhabdomyolysis was identified using hospital diagnosis code. We compared the clinical characteristics, in-hospital treatment, outcomes, and resource utilization between patients with and without rhabdomyolysis.

Results

A total of 13,805 hospital admissions for salicylate intoxication were studied. Of these, rhabdomyolysis developed in 258 (1.9%) admissions. The risk factors for rhabdomyolysis were age>20 years, male sex, volume depletion, hypokalemia, sepsis, and seizure. After adjustment for baseline clinical characteristics, salicylate intoxication patients with rhabdomyolysis required more invasive mechanical ventilation, and renal replacement therapy. Rhabdomyolysis was significantly associated with higher risk of failure of any organ systems, and in-hospital mortality. Length of hospital stay and hospitalization cost were higher when rhabdomyolysis occurred during hospital stay.

Conclusions

Rhabdomyolysis was not common in hospitalized patients for salicylate intoxication but it was associated with increased morbidity, mortality, and resource utilization.

Salicylate toxicity from chronic bismuth subsalicylate use

A 79-year-old man presented to the emergency department with a 1-week history of worsening confusion, falls and hearing impairment. An initial workup for infectious, metabolic and structural causes was unrevealing. However, further history discovered that he had been ingesting one to two bottles of Pepto-Bismol (bismuth subsalicylate) daily for gastro-oesophageal reflux symptoms. On his second day of admission, the plasma salicylate concentration was 2.08 mmol/L (reference range 1.10-2.20 mmol/L), despite no sources of salicylate in hospital. He was diagnosed with chronic salicylate toxicity and Pepto-Bismol use was discontinued. The patient was treated supportively with isotonic intravenous fluids only and plasma salicylate concentration fell to less than 0.36 mmol/L. Concurrently, all his symptoms resolved. This case highlights the potential adverse effects of over-the-counter medications. The diagnosis of chronic salicylate toxicity is challenging, specifically in the elderly and in undifferentiated presentations, as it can be missed if not suspected.

A Case of Salicylate Toxicity Presenting with Acute Focal Neurologic Deficit in a 61-Year-Old Woman with a History of Stroke

Patient: Female, 61-year-old

Final Diagnosis: Salicylate toxicity

Symptoms: Hemiparesis

Medication: Aspirin/Acetylsalicylic Acid

Clinical Procedure: —

Specialty: Toxicology

Safety Assessment of Salicylic Acid, Butyloctyl Salicylate, Calcium Salicylate, C12–15 Alkyl Salicylate, Capryloyl Salicylic Acid, Hexyldodecyl Salicylate, Isocetyl Salicylate, Isodecyl Salicylate, Magnesium Salicylate, MEA-Salicylate, Ethylhexyl Salicylate, Potassium Salicylate, Methyl Salicylate, Myristyl Salicylate, Sodium Salicylate, TEA-Salicylate, and Tridecyl Salicylate

Salicylic Acid is an aromatic acid used in cosmetic formulations as a denaturant, hair-conditioning agent, and skin-conditioning agent—miscellaneous in a wide range of cosmetic products at concentrations ranging from 0.0008% to 3%. The Calcium, Magnesium, and MEA salts are preservatives, and Potassium Salicylate is a cosmetic biocide and preservative, not currently in use. Sodium Salicylate is used as a denaturant and preservative (0.09% to 2%). The TEA salt of Salicylic Acid is used as an ultraviolet (UV) light absorber (0.0001% to 0.75%). Several Salicylic Acid esters are used as skin conditioning agents—miscellaneous (Capryloyl, 0.1% to 1%; C12–15 Alkyl, no current use; Isocetyl, 3% to 5%; Isodecyl, no current use; and Tridecyl, no current use). Butyloctyl Salicylate (0.5% to 5%) and Hexyldodecyl Salicylate (no current use) are hair-conditioning agents and skin-conditioning agents—miscellaneous. Ethylhexyl Salicylate (formerly known as Octyl Salicylate) is used as a fragrance ingredient, sunscreen agent, and UV light absorber (0.001% to 8%), and Methyl Salicylate is used as a denaturant and flavoring agent (0.0001% to 0.6%). Myristyl Salicylate has no reported function. Isodecyl Salicylate is used in three formulations, but no concentration of use information was reported. Salicylates are absorbed percutaneously. Around 10% of applied salicylates can remain in the skin. Salicylic Acid is reported to enhance percutaneous penetration of some agents (e.g., vitamin A), but not others (e.g., hydrocortisone). Little acute toxicity (LD50 in rats; >2 g/kg) via a dermal exposure route is seen for Salicylic Acid, Methyl Salicylate, Tridecyl Salicylate, and Butyloctyl Salicylate. Short-term oral, inhalation, and parenteral exposures to salicylates sufficient to produce high blood concentrations are associated primarily with liver and kidney damage. Subchronic dermal exposures to undiluted Methyl Salicylate were associated with kidney damage. Chronic oral exposure to Methyl Salicylate produced bone lesions as a function of the level of exposure in 2-year rat studies; liver damage was seen in dogs exposed to 0.15 g/kg/day in one study; kidney and liver weight increases in another study at the same exposure; but no liver or kidney abnormalities in a study at 0.167 g/kg/day. Applications of Isodecyl, Tridecyl, and Butyloctyl Salicylate were not irritating to rabbit skin, whereas undiluted Ethylhexyl Salicylate produced minimal to mild irritation. Methyl Salicylate at a 1% concentration with a 70% ethanol vehicle were irritating, whereas a 6% concentration in polyethylene glycol produced little or no irritation. Isodecyl Salicylate, Methyl Salicylate, Ethylhexyl (Octyl) Salicylate, Tridecyl Salicylate, and Butyloctyl Salicylate were not ocular irritants. Although Salicylic Acid at a concentration of 20% in acetone was positive in the local lymph node assay, a concentration of 20% in acetone/olive oil was not. Methyl Salicylate was negative at concentrations up to 25% in this assay, independent of vehicle. Maximization tests of Methyl Salicylate, Ethylhexyl Salicylate, and Butyloctyl Salicylate produced no sensitization in guinea pigs. Neither Salicylic Acid nor Tridecyl Salicylate were photosensitizers. Salicylic Acid, produced when aspirin is rapidly hydrolyzed after absorption from the gut, was reported to be the causative agent in aspirin teratogenesis in animals. Dermal exposures to Methyl Salicylate, oral exposures to Salicylic Acid, Sodium Salicylate, and Methyl Salicylate, and parenteral exposures to Salicylic Acid, Sodium Salicylate, and Methyl Salicylate are all associated with reproductive and developmental toxicity as a function of blood levels reached as a result of exposure. An exposure assessment of a representative cosmetic product used on a daily basis estimated that the exposure from the cosmetic product would be only 20% of the level seen with ingestion of a “baby” aspirin (81 mg) on a daily basis. Studies of the genotoxic potential of Salicylic Acid, Sodium Salicylate, Isodecyl Salicylate, Methyl Salicylate, Ethylhexyl (Octyl) Salicylate, Tridecyl Salicylate, and Butyloctyl Salicylate were generally negative. Methyl Salicylate, in a mouse skin-painting study, did not induce neoplasms. Likewise, Methyl Salicylate was negative in a mouse pulmonary tumor system. In clinical tests, Salicylic Acid (2%) produced minimal cumulative irritation and slight or no irritation(1.5%); TEA-Salicylate (8%) produced no irritation; Methyl Salicylate (>12%) produced pain and erythema, a 1% aerosol produced erythema, but an 8% solution was not irritating; Ethylhexyl Salicylate (4%) and undiluted Tridecyl Salicylate produced no irritation. In atopic patients, Methyl Salicylate caused irritation as a function of concentration (no irritation at concentrations of 15% or less). In normal skin, Salicylic Acid, Methyl Salicylate, and Ethylhexyl (Octyl) Salicylate are not sensitizers. Salicylic Acid is not a photosensitizer, nor is it phototoxic. Salicylic Acid and Ethylhexyl Salicylate are low-level photoprotective agents. Salicylic Acid is well-documented to have keratolytic action on normal human skin. Because of the possible use of these ingredients as exfoliating agents, a concern exists that repeated use may effectively increase exposure of the dermis and epidermis to UV radiation. It was concluded that the prudent course of action would be to advise the cosmetics industry that there is a risk of increased UV radiation damage with the use of any exfoliant, including Salicylic Acid and the listed salicylates, and that steps need to be taken to formulate cosmetic products with these ingredients as exfoliating agents so as not to increase sun sensitivity, or when increased sun sensitivity would be expected, to include directions for the daily use of sun protection. The available data were not sufficient to establish a limit on concentration of these ingredients, or to identify the minimum pH of formulations containing these ingredients, such that no skin irritation would occur, but it was recognized that it is possible to formulate cosmetic products in a way such that significant irritation would not be likely, and it was concluded that the cosmetics industry should formulate products containing these ingredients so as to be nonirritating. Although simultaneous use of several products containing Salicylic Acid could produce exposures greater than would be seen with use of baby aspirin (an exposure generally considered to not present a reproductive or developmental toxicity risk), it was not considered likely that consumers would simultaneously use multiple cosmetic products containing Salicylic Acid. Based on the available information, the Cosmetic Ingredient Review Expert Panel reached the conclusion that these ingredients are safe as used when formulated to avoid skin irritation and when formulated to avoid increasing the skin's sun sensitivity, or, when increased sun sensitivity would be expected, directions for use include the daily use of sun protection.

Drug-induced hyperthermic syndromes: part I. Hyperthermia in overdose

Drugs and natural compounds that affect the thermoregulatory system can induce or contribute to hyperthermia when used in excess. Hyperthermia associated with drug overdose is dangerous and potentially lethal. This article reviews the body's process of maintaining thermodynamic equilibrium, and describes the mechanisms by which it is influenced by sympathomimetic and anticholinergic drugs, salicylates, and thyroid replacement medications. Appropriate treatment strategies such as cooling and the administration of counteractive medications are discussed.

Elderly and drugs: risks and necessity of rational use

In recent decades, the world has undergone a demographic transformation with a rapid growth of the elderly population, resulting in an increased demand for funds to maintain their health and drug consumption. Pharmacokinetic and pharmacodynamic changes occurring in the elderly can interfere directly in the adverse effects of drugs and increase the risk of intoxication. In addition, there are external factors interfering with the pharmacotherapy of the elderly, such as inappropriate use and the lack of access to information. Many therapeutic classes of drugs should be used with caution or avoided in the elderly population, such as anti-inflammatory and some anti-hypertensive drugs, diuretics and digitalis. If not managed carefully, these medicines can affect the safety and quality of life in the elderly. Thus, the aim of this review was to identify drugs that should be used with caution in elderly patients in order to avoid intoxication and/or adverse drug events.

Neuropsychiatric consequences of cardiovascular medications

The use of cardiovascular medications can have a variety of neuropsychiatric consequences. Many cardiovascular agents cause higher rates of fatigue and sedation than placebo, and case reports of medication-induced mood syndromes, psychosis, and cognitive disturbances exist for many cardiovascular drugs. Depression has been associated with β-blockers, methyldopa, and reserpine, but more recent syntheses of the data have suggested that these associations are much weaker than originally believed. Though low cholesterol levels have been associated with depression and suicide, lipid-lowering agents have not been associated with these adverse effects. Finally, cardiovascular medications may have beneficial neuropsychiatric consequences; for example, the use of clonidine in patients with attention deficit-hyperactivity disorder, the use of prazosin for patients with post-traumatic stress disorder, and the use of propranolol for performance anxiety and akathisia.

Anesthesia in a patient with undiagnosed salicylate poisoning presenting as intraabdominal sepsis

An 81-year-old woman with unintentional salicylate intoxication presented with features of sepsis, abdominal pain, and tenderness. Laparotomy was performed to rule out acute cholecystitis. Anesthesia was complicated by severe hypercarbia despite hyperventilation, and progressive cardiovascular and neurologic deterioration postoperatively. The adverse neurologic, respiratory, and hepatic effects of abdominal surgery and general anesthesia probably potentiated salicylate toxicity and increased patient morbidity. Anesthesiologists should be aware of the protean manifestations of salicylate poisoning and consider it as a cause of "medical abdomen."