sychiatric side effects (PSEs) can be induced bythe pharmacological treatment of physical illnesses. Theclinical presentation of PSEs often resembles sponta-neous psychiatric syndromes (ie, noniatrogenic, naturallyoccurring diseases). PSEs can occur at usual doses, incases of intoxication, or during the days following
with-drawal of a given treatment. PSEs range from short-last-ing anxiety to severe confusion, and alleged cases
of sui-cide have even been reported.The Diagnostic and Statistic Manual
of Mental Disorders,Fourth Edition (DSM-IV)1defines
some dozens of cate-gories of PSE, according to the disorder and to
the incrim-inated substance, eg,persisting dementia
induced by seda-tives, hypnotics or anxiolytics. The DSM-IV categoriesinclude drugs for therapeutic purposes, medication
takenabusively, and other substances. The InternationalClassification of Diseases2is
very similar to DSM-IV in itscategorization, with minor differences in terms
of categorycodes.The challenge of PSEs in everyday practice is the diffi-culty in recognizing these frequent and potentially
dan-gerous situations. The diagnosis of PSEs raises
the samequestions as the diagnosis of any psychiatric sign orsymptom, which means that the clinician has to
considera rather long list of differential diagnoses. The
followingconcepts refer to PSEs, as well as to other kinds
of sideeffects: Exposure: The
period of time the patient received thedrug suspected of inducing a side effect. Dechallenge: The
interruption of the suspected med-ication, regardless of the remission of adverse
effects.Positive dechallenge means
that remission was tempo-rally associated with the interruption of medication. Rechallenge:The
reintroduction of the suspected drug.Positive rechallenge means
that symptom reappearancewas temporally associated with suspected drug rein-troduction.P h a r m a c o l o g i c a l a s p e c t s1 5 5Psychiatric side effects of medications prescribed in internal medicineRodrigo Casagrande Tango, MDPSeveral pharmacological treatments
used in internal med-icine can induce psychiatric side
effects (PSEs) that mimicdiagnoses seen in psychiatry. PSEs
may occur upon with-drawal or intoxication, and also at usual therapeuticdoses. Drugs that may lead to depressive,
anxious, or psy-chotic syndromes include corticosteroids,
isotretinoin, levo-dopa, mefloquine, interferon-,
and anabolic steroids, aswell as some over-the-counter medications.
PSEs are oftendifficult to diagnose and can be very
harmful to patients.PSEs are discussed in this review,
as well as diagnostic clues to facilitate their identification.Dialogues Clin Neurosci.
2003;5:155-165.Keywords: adverse
effect; psychiatry; mechanism; risk factor; diagnosis; meflo-quine; chloroquine; metronidazole;
isotretinoin; interferon; steroid; -blockerAuthor affiliations: Unitéde Psychopharmacologie Clinique, HôpitauxUniversitaires de Genève, Chêne-Bourg,
SwitzerlandAddress for correspondence: Unitéde Psychopharmacologie Clinique, 2, chemin
du Petit Bel-Air 1225 Chêne-Bourg,
Switzerland
(e-mail: rctango@web.de)