Amitriptyline Abuse and Misuse

Rapid Detection of Amitriptyline in Dried Blood and Dried Saliva Samples with Surface-Enhanced Raman Spectroscopy

There is growing demand for rapid, nondestructive detection of trace-level bioactive molecules including medicines, toxins, biomolecules, and single cells, in a variety of disciplines. In recent years, surface-enhanced Raman scattering has been increasingly applied for such purposes, and this area of research is rapidly growing. Of particular interest is the detection of such compounds in dried saliva spots (DSS) and dried blood spots (DBS), often in medical scenarios, such as therapeutic drug monitoring (TDM) and disease diagnosis. Such samples are usually analyzed using hyphenated chromatography techniques, which are costly and time consuming. Here we present for the first time a surface-enhanced Raman spectroscopy protocol for the detection of the common antidepressant amitriptyline (AMT) on DBS and DSS using a test substrate modified with silver nanoparticles. The validated protocol is rapid and non-destructive, with a detection limit of 95 ppb, and linear range between 100 ppb and 1.75 ppm on the SERS substrate, which covers the therapeutic window of AMT in biological fluids.

Dual effect of amitriptyline in the control of vascular tone: Direct blockade of calcium channel in smooth muscle cells and reduction of TLR4-dependent NO production in endothelial cells

BACKGROUND AND PURPOSE

Amitriptyline (AM) is a classical and typical tricyclic antidepressant drug. Despite its well-known effects on the nervous system, it has been described to work as a TLR4 antagonist and several clinical works suggested some unexpected cardiovascular effects. The role of amitriptyline on vascular tone is not clear, thus we hypothesized that amitriptyline has a double effect on vascular tone by both endothelial TLR4-dependent nitric oxide down-regulation and calcium channel blockade in smooth muscle cells.

EXPERIMENTAL APPROACH

Changes in isometric tension were recorded on a wire myograph. NO production was evaluated by fluorescence microscopy and flow cytometry in the mouse aorta and EAhy926 cells using DAF fluorescence intensity. Calcium influx was evaluated in A7r5 cells by flow cytometry. Western blot was used to analyze eNOS and nNOS phosphorylation.

KEY RESULTS

AM reduced PE-induced contraction by calcium influx diminution in smooth muscle cells (F/F₀ = 225.6 ± 15.9 and 118.6 ± 17.6 to CT and AM, respectively). AM impaired Ach-dependent vasodilation (Emax = 95.8 ± 1.4; 78.1 ± 1.8; 60.4 ± 2.9 and -7.4 ± 1.0 for CT, 0.01, 0,1 and 1 μmol/L AM, respectively) through reduction of calcium influx and NO availability and TLR4 antagonism in a concentration-dependent manner. AM or TLR4 gene deletion significantly reduced NO production (Fluorescence = 9503 ± 871.7, 2561 ± 282, 4771 ± 728 and 1029 ± 103 to CT, AM, TLR4^-/- and AM + TLR4^-/-, respectively) by an increase in nNOS^ser852 and reduction in eNOS^ser1177 phosphorylation in endothelial cells.

CONCLUSIONS AND IMPLICATIONS

Our data show that amitriptyline impaired vascular function through two different mechanisms: blockade of TLR4 in endothelial cells and consequent decrease in NO production and calcium influx reduction in smooth muscle and endothelial cells. We also suggest, for the first time, nNOS activity reduction by AM in non-neuronal cells.

A Focus on Abuse/Misuse and Withdrawal Issues with Selective Serotonin Reuptake Inhibitors (SSRIs): Analysis of Both the European EMA and the US FAERS Pharmacovigilance Databases

Despite increasing reports, antidepressant (AD) misuse and dependence remain underestimated issues, possibly due to limited epidemiological and pharmacovigilance evidence. Thus, here we aimed to determine available pharmacovigilance misuse/abuse/dependence/withdrawal signals relating to the Selective Serotonin Reuptake Inhibitors (SSRI) citalopram, escitalopram, paroxetine, fluoxetine, and sertraline. Both EudraVigilance (EV) and Food and Drug Administration-FDA Adverse Events Reporting System (FAERS) datasets were analysed to identify AD misuse/abuse/dependence/withdrawal issues. A descriptive analysis was performed; moreover, pharmacovigilance measures, including the reporting odds ratio (ROR), the proportional reporting ratio (PRR), the information component (IC), and the empirical Bayesian geometric mean (EBGM) were calculated. Both datasets showed increasing trends of yearly reporting and similar signals regarding abuse and dependence. From the EV, a total of 5335 individual ADR reports were analysed, of which 30% corresponded to paroxetine (n = 1592), 27% citalopram (n = 1419), 22% sertraline (n = 1149), 14% fluoxetine (n = 771), and 8% escitalopram (n = 404). From FAERS, a total of 144,395 individual ADR reports were analysed, of which 27% were related to paroxetine, 27% sertraline, 18% citalopram, 16% fluoxetine, and 13% escitalopram. Comparing SSRIs, the EV misuse/abuse-related ADRs were mostly recorded for citalopram, fluoxetine, and sertraline; conversely, dependence was mostly associated with paroxetine, and withdrawal to escitalopram. Similarly, in the FAERS dataset, dependence/withdrawal-related signals were more frequently reported for paroxetine. Although SSRIs are considered non-addictive pharmacological agents, a range of proper withdrawal symptoms can occur well after discontinuation, especially with paroxetine. Prescribers should be aware of the potential for dependence and withdrawal associated with SSRIs.

Case Report: Concurrent Clonidine Abuse and Opioid Use Disorder

Clonidine is a centrally acting alpha-2 selective adrenergic receptor agonist used to treat hypertension and to control or prevent withdrawal in patients with opioid and alcohol use disorders. Case reports describe abuse of clonidine alone or in combination with benzodiazepines, methadone, codeine, or heroin. Clonidine reportedly boosts and extends the opioid-related euphoria and reduces the amount of psychoactive drug needed. In this case report, we describe clonidine abuse and withdrawal management in an elderly patient with concurrent opioid use disorder. The usage of clonidine in the treatment of opioid detoxification remains controversial. Clonidine abuse is underestimated and requires more attention among health-care providers who concurrently prescribe clonidine and opioids. With the opioid epidemic becoming increasingly prevalent, physicians and other health-care providers must be vigilant in their opioid prescribing as well as concurrent prescribing of other psychoactive pharmacologic agents.

Using Social Listening Data to Monitor Misuse and Nonmedical Use of Bupropion: A Content Analysis

Background

The nonmedical use of pharmaceutical products has become a significant public health concern. Traditionally, the evaluation of nonmedical use has focused on controlled substances with addiction risk. Currently, there is no effective means of evaluating the nonmedical use of noncontrolled antidepressants.

Objective

Social listening, in the context of public health sometimes called infodemiology or infoveillance, is the process of identifying and assessing what is being said about a company, product, brand, or individual, within forms of electronic interactive media. The objectives of this study were (1) to determine whether content analysis of social listening data could be utilized to identify posts discussing potential misuse or nonmedical use of bupropion and two comparators, amitriptyline and venlafaxine, and (2) to describe and characterize these posts.

Methods

Social listening was performed on all publicly available posts cumulative through July 29, 2015, from two harm-reduction Web forums, Bluelight and Opiophile, which mentioned the study drugs. The acquired data were stripped of personally identifiable identification (PII). A set of generic, brand, and vernacular product names was used to identify product references in posts. Posts were obtained using natural language processing tools to identify vernacular references to drug misuse-related Preferred Terms from the English Medical Dictionary for Regulatory Activities (MedDRA) version 18 terminology. Posts were reviewed manually by coders, who extracted relevant details.

Results

A total of 7756 references to at least one of the study antidepressants were identified within posts gathered for this study. Of these posts, 668 (8.61%, 668/7756) referenced misuse or nonmedical use of the drug, with bupropion accounting for 438 (65.6%, 438/668). Of the 668 posts, nonmedical use was discouraged by 40.6% (178/438), 22% (22/100), and 18.5% (24/130) and encouraged by 12.3% (54/438), 10% (10/100), and 10.8% (14/130) for bupropion, amitriptyline, and venlafaxine, respectively. The most commonly reported desired effects were similar to stimulants with bupropion, sedatives with amitriptyline, and dissociatives with venlafaxine. The nasal route of administration was most frequently reported for bupropion, whereas the oral route was most frequently reported for amitriptyline and venlafaxine. Bupropion and venlafaxine were most commonly procured from health care providers, whereas amitriptyline was most commonly obtained or stolen from a third party. The Fleiss kappa for interrater agreement among 20 items with 7 categorical response options evaluated by all 11 raters was 0.448 (95% CI 0.421-0.457).

Conclusions

Social listening, conducted in collaboration with harm-reduction Web forums, offers a valuable new data source that can be used for monitoring nonmedical use of antidepressants. Additional work on the capabilities of social listening will help further delineate the benefits and limitations of this rapidly evolving data source.

Combined abuse of clonidine and amitriptyline in a patient on buprenorphine maintenance treatment

Buprenorphine/naloxone maintenance therapy is often prescribed in primary care to treat opioid dependence. Previous reports have described concomitant abuse of opioids and clonidine. In this case, a primary care patient on buprenorphine/naloxone maintenance therapy demonstrating altered mental status, hallucinations, falls, and rebound hypertension was found to be concomitantly abusing clonidine and amitryptyline, which share metabolic pathways with buprenorphine. Clinicians should be aware of patients' combining amitryptyline, clonidine, and gabapentin with buprenorphine to achieve a mood altering state, avoid co-prescribing them if possible, and maintain communication with pharmacies and other providers when they are prescribed.

Abuse and misuse of antidepressants

BACKGROUND

Rates of prescription drug abuse have reached epidemic proportions. Large-scale epidemiologic surveys of this under-recognized clinical problem have not included antidepressants despite their contribution to morbidity and mortality. The purpose of this review is to look specifically at the misuse of antidepressants and how this behavior may fit into the growing crisis of nonmedical use of prescription drugs.

METHODS

We conducted a comprehensive search on PubMed, Medline, and PsycINFO using the search terms "antidepressant", "abuse", "misuse", "nonmedical use", "dependence", and "addiction", as well as individual antidepressant classes (eg, "SSRI") and individual antidepressants (eg, "fluoxetine") in various combinations, to identify articles of antidepressant misuse and abuse.

RESULTS

A small but growing literature on the misuse and abuse of antidepressants consists largely of case reports. Most cases of antidepressant abuse have occurred in individuals with comorbid substance use and mood disorders. The most commonly reported motivation for abuse is to achieve a psychostimulant-like effect. Antidepressants are abused at high doses and via a variety of routes of administration (eg, intranasal, intravenous). Negative consequences vary based upon antidepressant class and pharmacology, but these have included seizures, confusion, and psychotic-like symptoms.

CONCLUSION

The majority of individuals prescribed antidepressants do not misuse the medication. However, certain classes of antidepressants do carry abuse potential. Vulnerable patient populations include those with a history of substance abuse and those in controlled environments. Warning signs include the presence of aberrant behaviors. Physicians should include antidepressants when screening for risky prescription medication use. When antidepressant misuse is detected, a thoughtful treatment plan, including referral to an addiction specialist, should be developed and implemented.

Current and Emerging Detoxification Therapies for Critical Care

Toxicity resulting from prescription drugs such as tricyclic antidepressants and cardioactive steroids, as well as drugs of abuse and exposure to environmental chemicals, represents a major need for detoxification treatments. Particles and colloids, antibody fragments (Fab), and indirect treatment methods such as macroemulsions, are currently being developed or employed as detoxification therapies. Colloids, particles, and protein fragments typically mitigate toxicity by binding to the toxin and reducing its concentration in vital organs. Indirect methods such as macroemulsions and sodium bicarbonate act directly on the affected organs, rather than the toxin. In this review, key design parameters (i.e. binding affinity, biocompatibility, pharmacokinetics) are discussed for each type of detoxification treatment. In addition, some of the latest research in each area is reviewed.

Venlafaxine dependence in a patient with a history of alcohol and amineptine misuse

BACKGROUND

Venlafaxine is an inhibitor of neuronal serotonin and noradrenaline re-uptake and a weak inhibitor of dopamine re-uptake. There was no indication of problems of abuse/dependence during the clinical trials.

CASE DESCRIPTION

A 53-year-old client with a history of alcohol and amineptine misuse and a long history of recurrent depression, for which he was prescribed venlafaxine tablets. Over time, he increased the dosage to 50 tablets daily (3750 mg). Large venlafaxine dosages produced amphetamine-like effects, due possibly to the related increase in dopamine turnover. Once hospitalized for detoxification, the patient had a symptomatology which was consistent with a serotonergic discontinuation syndrome.

CONCLUSIONS

Physicians should be aware that patients with a history of drug and alcohol abuse might develop venlafaxine dependence.

Massive intoxication involving unusual high concentration of amitriptyline

Amitriptyline is a tricyclic antidepressant widely used in the treatment of depression. Antidepressant drugs are among the most commonly encountered causes of self-poisoning, as illustrated by several published cases in the literature. This investigation reports a case of massive amitriptyline intoxication, involving a 44-year old female found dead in bed. The presence of this tricyclic antidepressant was revealed by a routine screening procedure. The concentration was calculated by gas chromatography/ electron ionization-mass spectrometry in the selected ion monitoring mode after solid-phase extraction using proadifen as internal standard and was in the post-mortem whole blood sample 85.9 mug/mL. This value was much higher than the reported toxic values ever found in the literature, and may therefore have caused the victim's death. Nortriptyline was also detected in the toxic concentration range, as well as therapeutic levels of diazepam and nor-diazepam. Taking into account both the available circumstantial information and toxicological results, it is very likely that death was caused by self-poisoning. Human & Experimental Toxicology (2007) 26, 667-670.

A Fatal Doxepin Poisoning Associated With a Defective CYP2D6 Genotype

It has been suggested that the polymorphism of the CYP2D6 gene can contribute to occurrence of fatal adverse effects. We therefore investigated postmortem toxicology cases of fatal drug poisonings related to CYP2D6 substrates, with the manner of death denoted as accidental or undetermined. CYP2D6 genotypes were determined in 11 consecutive cases with samples available for DNA analysis. A case of fatal doxepin poisoning with an undetermined manner of death was found to coincide with a completely nonfunctional CYP2D6 genotype (*3/*4), indicating a total absence of CYP2D6 enzyme and suggesting a poor metabolizer phenotype. The doxepin concentration was 2.4 mg/L, the concentration of nordoxepin 2.9 mg/L, and the doxepin/nordoxepin ratio 0.83, the lowest found among the 35 nordoxepin-positive postmortem cases analyzed during the same year. No alcohols or other drugs were detected in the case. The CYP2C19 genotype was determined as that of an extensive metabolizer. The high N-desmethylmetabolite concentration is not consistent with acute intoxication. It is therefore probable that the defective genotype has contributed to the death, possibly involving repeated high dosage of doxepin. Our case strongly emphasizes that a pharmacogenetic analysis in postmortem forensic setting may reveal new insight to the cause or manner of death.