Adverse psychiatric reactions to prescribed drugs - information resources

Pharmaceutical industry funded web sites :

  • Data Sheets for all drugs are on the ABPI web site www.medicines.org.uk and the data sheet is called SPC or Summary of Product Characteristics.
  • You can also sign up for drug safety alerts on the MHRA web site www.mhra.gov.uk - data from the Yellow card reporting system can also be accessed on the MHRA web site by clicking Yellow Card reporting then in left menu DAPs or Drug Analysis Prints.
  • Reports of ADRs by patients and health professionals can be made on line at www.yellowcard.gov.uk

Most of the following text is quoted from the Textbook of Adverse Drug Reactions - Davies 1991 Oxford University Press (OUP) Psychiatric disorders section by K. Davison and F. Hassanyeh (a section in this manual is by Professor Heather Ashton)

"Adverse drug reactions account for a substantial amount of psychiatric morbidity (illness) which is increasing as new and ever more potent drugs are introduced. A survey of adverse drug reactions in general practice revealed that neuropsychiatric reactions accounted for 30 per cent of cases, second only to gastrointestinal reactions (Martys 1979) The Boston Collaborative Drug Surveillance Program (BCDSP 1971) recorded adverse psychiatric reactions in 2.7 per cent of 9000 hospital patients receiving non- psychiatric drugs.

The difficulties attaching to establishing the validity of any alleged drug reaction are greatly magnified for psychiatric reactions. The latter may be delayed in onset, and some reactions may persist for weeks or months after drug withdrawal.

The chapter continues after elaborating on the difficulties.

"Many reports emanate from non-psychiatrists, who tend to equate hallucinations and delusions with ' psychosis' or even 'schizoprenia' and apathy with ' depression' when the correct diagnosis is 'delirium'.

Application of a recognized diagnostic system, such as the International Classification of Diseases (ICD-9s (WHO 1977) or that of the American Psychiatric Association (DSM-111-R) (APA 1987) would help to obviate this difficulty. These problems emphasize importance of national systems of reporting adverse drug reactions.

Predisposing factors to adverse psychiatric reactions

An important variable in the production of adverse psychiatric reactions is personal predisposition. The risk of increased in those with pre-existing impairment of brain function, such as the elderly or brain-damaged, or with past or present psychiatric illness, or a history of alcohol or drug abuse, but those with unblemished psychiatric records are by no means immune. Although a family history of affective disorder (depression or mania) predisposes to the drug precipitation of the same conditions. (Whitlock and Evans 1978), the relationship is less clear - cut for paranoid or schizophreniform psychoses (Davison 1976). These disorders can also appear in those without such predisposition.

Other predisposing factors include extreme youth (Prescott 1979), concurrent physical disease (James 1975), and stressful environments, such as intensive treatment units (Tomlin 1977; Davison 1989a)

Types of Reaction

The vast majority of adverse psychiatric drug reactions are of Type A in that they are dose-dependent or recognizably related to the known pharmacological properties of the drug. Even when a reaction occurs at therapeutic plasma drug levels there is often an interaction of an identifiable drug effect with individual predisposition." END OF QUOTE

The following is quoted from 'Iatrogenic Diseases by D'Arcy and Griffin 1986 (OUP)

If an unexpected psychiatric disturbance arises suddenly in a person of good previous personality, shortly after a drug of any sort has been taken, no matter how harmless it usually is, it is clearly wise to suspect a drug-induced reaction and, if possible, to discontinue or reduce the dose of the suspected medication. It is also good practice to avoid unnecessary polypharmacy, to attempt to treat one psychiatric condition with one drug if possible, and to remember that the use of two drugs from the same group (antidepressant, neuroleptic, minor tranqullizer, etc.) can rarely, if ever, be justified.

Delirium

A very wide range of drugs have been associated with toxic confusional reactions (acute brain syndrome) which are characterized by a fluctuating clouding of consciousness, restlessness, emotional changes (usually fear and perplexity, and paranoid delusions and/ or visual hallucinations in severe cases.)

Detailed descriptions of delirious states were given in the classic paper by Wolfe and Curran (1935) who reviewed 106 cases associated with 27 different precipitating noxious agents. The only drugs involved in these cases were alcohol, barbiturates, bromide, lead and copper. Wider range of drugs can be associated with such reactions, either during administration or in withdrawal."

Some Psychiatric Effects: list modified from McConnell and Duffy, 1994 accessed from the Maudsley Hospital prescribing guidelines

Drug

Psychiatric Effects

Antihypertensive drugs

 

Clonidine

depression, mania, agitation

Propanolol

depression, mania, delirium, psychosis

Nifedipine

depression

Captopril

mania, agitation

Antiarrhythmics

 

Procaninamide

depression, mania, delirium, psychosis

Lignocaine

depression, delirium, psychosis

Disopyramide

delirium, psychosis

Antimicrobial Agents

 

Penicillins

depression, agitation, visual halucinations

Tetracycline

depression, hallucinations

Cephalosporins

delirium, psychosis

Antimalarials

psychosis, visual hallucinations

Antiparkinson drugs

 

Anticholinergics

delirium, psychosis, visual hallucinations, dementia

Amantadine

depression, agitation, delirium, psychosis visual hallucinations

Levodopa

depression, mania, anxiety, agitation, psychosis visual hallucinations, delirium, cognitive impairment

Antihistamines

 

H1 Blockers (diphenhydramine)

delirium

H2 Blockers (cimetidine)

depression, mania, delirium, psychosis, visual hallucinations

Antineoplastic drugs

 

Interferon

depression, agitation, delirium

Vincristine

depression

C-asparaginase

depression, delirium, psychosis

Endocrine Agents

 

Corticosteroids

depression, mania, psychosis, delirium

Oral contraceptives

depression

Thyroxine

anxiety, agitation, mania, psychosis, visual hallucinations

Antiepileptic drugs

 

Barbiturates (phenobarbitone, primidone)

hyperactivity (especially in children), sedation, sexual dysfunction, aggression, learning deficits, cognitive impairmant, depression, personality change
Positive effects: anxiolytic/hypnotic
(hypnotic, or soporific drugs produce sleep by depressing brain function and often cause hangover effects in the morning)

Benzodiazepines: (clonazepam, diazepam)

aggression, confusion, depression, disinhibition, irritability, cognitive impairment
Positive effects: anxiolytic/hypnotic; antimanic (clonazepam)

Carbamazepine

depression, irritability, sexual dysfunction, mania
Positive effects: antidepressant, antimanic, treatment of aggression and bipolar disorder

Clobazam

similar side effect profile to other benzodiazepines but may have lower overall incidence of cognitive and behavioural side effects anxiolytic/positive psychotropic effects

Gabapentin

sedation, ataxia, (shaky movements) aggression and hyperactivity (children); Few drug interactions, positive psychotropic effects,

Hydantoins (phenytoin)

sedation, ataxia, dementia, affective disorder, confusion, cognitive impairment, progressive encephalopathy (disease that affects functioning of the brain)
Positive effects? antiaggressive, anxiolytic effects

Lamotrigine

may have added toxicity when used with carbamazepine: ataxia, dizziness; positive psychotropic effects

Succinimides (ethosuximide, methsuximide)

Psychosis ("alternating psychosis"- adolescents, young adults) Drowsiness, insomnia, irritability, cognitive effects, personality change, Positive effects: improvement in attention/concentration (likely related to seizure improvement)

Topirimate

sedation, confusion, cognitive dysfunction, asthenia (weakness loss of strength)

Valproate

progressive encephalopathy, dementia, depression, extrapyramidal effects (muscle spasms etc)
Positive effects: antimanic, treatment of aggression and bipolar disorder

Vigabatrin

depression and psychosis


Glossary    |    Disclaimer
Copyright © APRIL Ltd.