psychiatric drugs Flashcards
SSRI examples
citalopram
fluoxetine
sertraline
ssri mechanism
inhibit reuptake of 5-HT by the PREsynaptic neurone, so increase the [5-HT] in the synaptic cleft
Side effects of SSRIs
Transient GI disturbance
lower libido
sexual problems
headache
anxiety
TCA examples
amitriptyline
imipramine
TCA indication
depression anxiety OCD chronic pain nocturnal enuresis
side effects of TCAs
Anticholinergic: dry mouth blurred vision constipation urinary retention drowsiness
CVS
postural hypotension
arrhythmias
TOXICITY IN OD cardiotoxic resp failure seizures convulsions coma
TCA contraindication
recent MI
arrhythmias
Mania is relative
MAOI examples
reversible and irreversible
reversible (RIMA): moclobemide
irreversible: phenelezine
MAOI side effects
CVS
Neuropsych
Sexual
GI
Hepatic
MAOI contraindications
+/- mania
hepatic impairment
cerebrovascular disease
phaeochromocytoma
MAOI cautions
Must carry a card indicating that they are taking MAOIS
Foods to avoid: cheese, pickled food, meats, broad beens, yeast extracts
Avoid undercooked food
avoid alcohol
otehr antidepressants not to be prescribed until 2weeks after stopping MAOis
LITHIUM indicaitons
BPAD: Maniia
Augments antidepressants in refractory depression
Tx of borderline and impulsive personality disorder
clozipine-related neutropenia, as it increases neutrophil count both acutely and chronically
Side effects of lithium
General
- weight gain
- fine tremor BUT COARSE tremor in TOXICITY
- muscle weakness
- oedema
GI:
- diarrhoe
- nausea
- vomiting
- metallic taste
renal
- nephrogenic DI
- long term -> renal scarring
Endocrine:
- hypothyroidism»_space; chech TFTs
- PTH and Ca disturbances
Cardiac:
T wave inversion
PREGNANCY: Ebstein’s anomaly especially in 1st trimester
Haem:
LEUCOCYTOSIS
lithium monitoring, toxic levels and Sx
serum levels 12 hPOST-DOSE, keep at 0.6-1.0mmol/l
toxic >1.5mmol/L
GI effects (anorexia, nausea, diarrhoea),
CNS effects (muscle twitching, weakness, ataxia, COARSE tremor);
> 2mmol/l: seizures can progress to death.
sodium valproate indications
antiepileptic
mood stabiliser
sodium valproate contraindications
acute porphyria, severe liver dysfunction
pregnancy: neural tube and craniofacial defects
Sodium vlaproate side effects:
sedation, cerebellar (tremr, ataxia), headache, GI upset, weight gain…
Sodium valproate:
Nausea is very common (take w food).
Valproate
Appetite↑, weight gain
Liver failure (watch lft esp. during 1st 6 months)
Pancreatitis
Reversible hair loss (grows back curly)
Oedema
Ataxia
Teratogenicity, tremor, thrombocytopenia
Encephalopathy (due to hyperammonaemia)
rarely suicidal thoughts
CARBAMAZEPINE/ indicaitons
Antiepileptic (but NOT absences),
mood stabiliser,
analgesic (neuralgia ( post-herpetic, trigeminal, DM-related);
side effects of carbamazepine
leucopenia, diplopia, blurred vision, impaired balance - dizziness, drowsiness, mild generalized erythematous rash, SIADH.
teratogen: neural tube
lamotrigine indications
epilepsy (esp partial, 1° or 2° generalised tonic–clonic).
lamotrigine side effects
cerebellar symptoms
skin reactions - often severe: SJS
blood disorders: low Hb, Low WCC, low paltelets
N&V
warning for patients on lamotrigine
report rash and any flu-like symptoms, signs of infection, bruising. DOn’t stop tablets suddenly
phenytoin indications
antiepileptic (blocks Na channels, stabilises neuronal membranes)
status epilepticus, tonic–clonic seizures, partial seizures
phenytoin side effecsts
SE (acute): dose-dependent: drowsiness (also confusion/dizziness), cerebellar fx, rash (common cause of intolerance and rarely ⇒SJS/TEN), N&V, diplopia, dyskinesia (esp orofacial).
If iv, risk of ↓BP, arrhythmias* (esp ↑QTc), ‘purple glove syndrome’ (hand damage distal to injection site), CNS/respiratory depression.
SE (chronic): gum hypertrophy, coarse facies, hirsutism, acne, l ow folate (⇒megaloblastic ↓Hb), Dupuytren’s, peripheral neuropathy, rickets, osteomalacia. Rarely, blood disorders, hepatotoxicity, suicidal thoughts/behaviour.
naloxone
opioid receptor antagonist
naltrexone
Opioid antagonist: ↓s euphoria of opioids if dependence and ↓s craving and relapse rate in alcoholic withdrawal (opioids thought to mediate alcohol addiction; not licensed for this in UK ).
Use: Opioid and alcohol withdrawal; start >1 wk after stopping
CI: if still taking opioids (can precipitate withdrawal), L (inc acute hepatitis).
alcohol detox acute
Chlordiazepoxide usually first line, but diazepam preferred if Hx of seizures (esp if occurred in context of alcohol withdrawal).
• If significant liver failure (↑AST or ALT) - shorteracting benzodiazepines (oxazepam or lorazepam). Only start once acute alcohol intoxication has resolved as benzodiazepines are CId in this state.
METHADONE
Opioid agonist: ↓euphoria, long t1/2 (→↓withdrawal symptoms) compared with other opioids.
Use: opioid dependence as aid to withdrawal.
CI/Caution/SE/Interactions: as morphine but levels not ↑by ritonavir, but are by voriconazole and cimetidine and ↑risk of arrhythmias with atomoxetine. Can ↑QTc (caution if FHx of sudden death).
Dose: individual requirements vary widely according to level of previous abuse
Consider the following as aids: in alchoholics
- Acamprosate: modulates alcohol withdrawal fx & limits –ve reinforcement of drinking cessation ⇒↓cravings and ↓relapse rate.
- Disulfiram: ⇒unpleasant symptoms if alcohol consumed.
- Naltrexone: ↓s pleasurable fx of alcohol and ↓s craving and relapse rate.
• Drugs for rapid tranquilisation of an agitated patient:
Haloperidol, lorazepam, promethazine
good for/reasons to choose Antipsychotics
Taking benzodiazepines, elderly (use with caution, esp if ↑ risk of CVA), delirium (non-alcohol withdrawal), psychosis ( hallucinations/ delusions /schizophrenia
bad for/reasons to not give Antipsychotics
Antipsychotic-naive, alcohol withdrawal, cardiac disease, movement disorder
PROMETHAZINE is what
Sedating antihistamine.
Use: insomnia. Also used iv/im for anaphylaxis and po for symptom relief in chronic allergies.
CI: CNS depression/coma, MAOI w/in 14 days.
Caution: urinary retention, ↑prostate, glaucoma, epilepsy, IHD, asthma, porphyria, pyloroduodenal obstruction, R (↓dose), L (avoid if severe)/P/B/E.
SE: antimuscarinic fx - hangover sedation, headache.
Warn: can ↓ability at driving/skilled tasks.
EXTRAPYRAMIDAL EFFECTS of antipsychotics
Abnormalities of movement control arising from dysfunction of basal ganglia.
• Parkinsonism: rigidity and bradykinesia tremor.
• Dyskinesias (abnormal involuntary movements); commonly:
– Dystonia (abnormal posture): dynamic (e.g. oculogyric crisis) or static (e.g. torticollis).
– Tardive (delayed onset) dyskinesia: esp orofacial movements.
– Others: tremor, chorea, athetosis, hemiballismus, myoclonus, tics.
• Akathisia (restlessness): esp after large antipsychotic doses.
All are commonly caused by antipsychotics (esp older ‘typical’ drugs) and are a rare complication of antiemetics (e.g. metoclopramide, rochlorperazine – esp in young women).
