Clinically Significant Psychotropic Drug-Drug Interactions in the Primary Care Setting

Abstract

In recent years, the growing numbers of patients seeking care for a wide range of psychiatric illnesses in the primary care setting has resulted in an increase in the number of psychotropic medications prescribed. Along with the increased utilization of psychotropic medications, considerable variability is noted in the prescribing patterns of primary care providers and psychiatrists. Because psychiatric patients also suffer from a number of additional medical comorbidities, the increased utilization of psychotropic medications presents an elevated risk of clinically significant drug interactions in these patients. While life-threatening drug interactions are rare, clinically significant drug interactions impacting drug response or appearance of serious adverse drug reactions have been documented and can impact long-term outcomes. Additionally, the impact of genetic variability on the psychotropic drug’s pharmacodynamics and/or pharmacokinetics may further complicate drug therapy. Increased awareness of clinically relevant psychotropic drug interactions can aid clinicians to achieve optimal therapeutic outcomes in patients in the primary care setting.

Analysis of Potential Drug Interactions in Brazilian Mental Health Services: Prevalence and Associated Factors

“…5 Drug interactions that involve psychotropic primarily compromise the metabolization process. Interactions may considerably raise the risk of intoxication, due to the inhibition of some cytochrome P450 isoenzymes, and exacerbate adverse reactions, 6 as occurs in several antipsychotic drugs. 1 Other interactions may trigger a reduction in the plasma concentration of a number of drugs, or even specific syndromes and symptoms.…”

“…1 Other interactions may trigger a reduction in the plasma concentration of a number of drugs, or even specific syndromes and symptoms. 6 These changes in pharmacokinetic and pharmacodynamics aspects may interfere in the main results that the patient seeks to achieve, namely, symptom elimination, quality of life and disease stabilization. 6 Drug interaction studies conducted at mental health outpatient facilities are scarce, 7 and most are restricted to a hospital setting, 8 although is an important aspect to consider in therapeutic planning and patient safety.…”

“…6 These changes in pharmacokinetic and pharmacodynamics aspects may interfere in the main results that the patient seeks to achieve, namely, symptom elimination, quality of life and disease stabilization. 6 Drug interaction studies conducted at mental health outpatient facilities are scarce, 7 and most are restricted to a hospital setting, 8 although is an important aspect to consider in therapeutic planning and patient safety. Psychosocial Care Centers (CAPS -from Portuguese Centro de Atenção Psicossocial) are strategic services belonging to the Psychosocial Care Network and the Brazilian health system.…”

Lurasidone drug-drug interaction studies: a comprehensive review

“…It has been estimated that this enzyme metabolizes 50% of marketed drugs [15], including many psychotropic medications such as antidepressants and antipsychotic agents [16,17]. Circulating plasma/serum concentrations of such drugs may be influenced by coadministration of drugs that inhibit or induce CYP3A4 [18]. In Study 1, serum concentration of lurasidone was increased in the presence of ketoconazole, an effect consistent with inhibition of CYP3A4 by ketoconazole.…”

Psychiatric treatment considerations with direct acting antivirals in hepatitis C

“…In theory, inhibition of P-gp may lead to increased exposure of the antipsychotic in the CSF, and may be associated with enhanced effectiveness or toxicity [79]. Despite the absence of documented metabolic drug interactions, caution is to be exercised with known substrates of P-gp (quetiapine, risperidone, olanzapine) and DAAs.…”