Mental health Flashcards
Benzodiazepines
E.g. diazepam, lorazepam, temazepam
Use: first-line for seizures and status epilepticus, first-line for alcohol withdrawal reactions, sedation for interventional procedures, short-term treatment of severe anxiety or insomnia
MOA: facilitate and enhance the binding of GABA to GABAa receptor, causing reduced anxiety, sleepiness, sedation and anticonvulsive effects.
Adverse effects: dose-dependent drowsiness, sedation and coma. Loss of airway reflexes in OD (leading to airway obstruction and death). Dependence and withdrawal reaction.
Cautions: dose reduction in elderly
CI: respiratory impairment, neuromuscular disease (myasthenia gravis), liver failure (precipitate hepatic encephalopathy)
Interactions: increased effects by CYP inhibitors (amiodarone, diltiazem, macrolides, fluconazole, protease inhibitors)
SSRIs
E.g. citalopram, fluoxetine, paroxetine, sertraline
Use: first-line for moderate-severe depression, panic disorder, OCD
MOA: selective serotonin reuptake inhibitors, preventing neuronal uptake of serotonin and increasing its availability for neurotransmission
Adverse effects: GI upset, weight and appetite disturbance, hypersensitivity reactions
Cautions:
CI: poorly controlled epilepsy, mania, peptic ulcer disease, hepatic impairment
Interactions: MAOi, drugs which prolong the QT interval
SNRIs
SNRIs
E.g. duloxetine, venlafaxine
Use: second-line for depression, GAD
MOA: serotonin and NA reuptake inhibitor, increasing neurotransmitter availability for neurotransmission. Improve mood and physical symptoms in depression.
Adverse effects: GI upset, CNS effects (headache, abnormal dreams, insomnia, confusion, convulsions), hypoNa+, serotonin syndrome, suicidal ideation
Cautions: reduce dose in hepatic or renal impairment, elderly are at risk of adverse effects, avoid venlafaxine in arrhythmias, sudden drug withdrawal (GI upset, neurological and influenza-like symptoms, sleep disturbance; this more likely with venlafaxine)
Interactions: increased risk of adverse effects when combined with SSRIs
Reboxetine
Use: major depression
MOA: Selective NA reuptake inhibitor
Adverse effects: accommodation disorder, akathisia, anxiety, decreased appetite, chills, constipation, dizziness, dry mouth, headache, hyperhidrosis, HTN, hypotension, insomnia, nausea, palpitations, paraesthesia, sexual dysfunction, skin reactions, tachycardia, taste altered
Cautions: bipolar, CVD, epilepsy, BPH, angle-closure glaucoma, urinary retention, hepatic impairment
Mirtazapine
Use: second-line for depression, GAD
MOA: serotonin and NA reuptake inhibitor, increasing neurotransmitter availability for neurotransmission. Improve mood and physical symptoms in depression. Also is a potent antagonist at H1 receptors, but notmuscarinic.
Adverse effects: GI upset, CNS effects (headache, abnormal dreams, insomnia, confusion, convulsions), hypoNa+, serotonin syndrome, suicidal ideation
Cautions: reduce dose in hepatic or renal impairment, elderly are at risk of adverse effects
Interactions: increased risk of adverse effects when combined with SSRIs
TCAs
E.g. amitriptyline, imipramine, lofepramine
Use: moderate-severe depression (second-line), neuropathic pain
MOA: inhibit neuronal reuptake of 5HT and NA from synaptic cleft, increasing their availability for neurotransmission. Improve mood and physical symptoms. Also block muscarinic, H1, alpha1, alpha 2 and D2 receptors.
Adverse effects: antimuscarinic effects (dry mouth, constipation, urinary retention, blurred vision), sedation and hypotension (both due to H1 and alpha 1 blockade). Arrhythmias, ECG changes (QT and QRS prolongation), convulsions, hallucinations, mania, breast changes, sexual dysfunction and EPSEs (last 3 due to DA blockade). OD can cause severe hypotension, arrhythmias, convulsions, coma and respiratory failure. Sudden withdrawal can cause GI upset, neuro and influenza-like symptoms.
Cautions: elderly, epilepsy or CVD (adverse effect risk is heightened). BPH, glaucoma or patients who are constipated may have their condition worsened.
Interactions: do not give with MAOi (both drugs have the same MOA).
Phenelzine
Non-selective MAOIs
Use: depressive illness
MOA: irreversible inhibition of IC MAO, causing accumulation of monoamines
Adverse effects: postural hypotension, hepatitis, HTN
Cautions: acute porphyria, blood disorder, concurrent ECT, DM, elderly, epilepsy, severe HTN, tyramine-rich food
CI: cerebrovascular disease, manic phase, phaeochromocytoma, severe CVD
Moclobemide
Use: depressive illness, social anxiety disorder
MOA: reversible inhibitors of monoamine oxidase A
Adverse effects: anxiety, constipation, diarrhoea, dry mouth, dizziness, headache, hypotension, irritability, nausea, paraesthesia, skin reactions, sleep disorder, vomiting
Cautions: agitation, bipolar (may induce mania), thyrotoxicosis
CI: acute confusion, pheochromocytoma
Opioid withdrawal
Methadone and buprenorphine are use as substitution therapy in opioid dependence.
Buprenorphine: opioid-receptor partial agonist. Less sedating, fewer drug interactions.
Methadone: long-acting opioid agonist.
Smoking cessation
Drug therapy to control physical symptoms of nicotine withdrawal is used alongside non-pharmacological methods to address psychological/behavioural aspects of dependence.
Nicotine activates nicotinic ACh receptors in the CNS, increasing NTM levels and causing euphoria/relaxation. Withdrawal causes intense cravings, anxiety, depression and irritability, along with increased appetite and weight gain.
MOA: NRT prevents withdrawal symptoms by maintaining receptor activation. Varenicline is a partial agonist of the nicotinic receptor, reducing withdrawals symptoms and the rewarding symptoms of smoking (prevents binding of tobacco-derived nicotine). Bupropion increases conc. of NA and DA in the synaptic cleft by inhibiting reuptake.
Adverse effects: local irritation, GI upset, palpitations and abnormal dreams. Varenicline may cause nausea, headache, insomnia, abnormal dreams, suicidal ideation. Bupropion may cause dry mouth, GI upset, neurological and psychiatric effects. Skin rashes are common.
Cautions: haemodynamically unstable patients, those at risk of seizures, psychiatric disease, hepatic or renal impairment.
Interactions: Bupropion is metabolised by cytochrome P450 so levels are increased by CYP inhibitors (valproate) and reduced by inducers (phenytoin, carbamazepine).
Alcohol withdrawal and dependence
Chlordiazepoxide - long-acting benzo, for acute withdrawal
Pabrinex/thiamine - Wernicke’s prophylaxis and in acute withdrawal
Acamprosate - to maintain abstinence
Naltrexone - prevent relapse in opioid or alcohol dependent patients
Disulfiram - as an adjunct in the treatment of dependence
Lorazepam - first line in delirium tremens
Lithium
Use: mania, bipolar disorder, recurrent depression, aggressive or self-harming behaviour
MOA: unknown
Adverse effects: rarely causes nephropathy. Long-term use may cause thyroid disorder and mild cognitive impairment.
Cautions: avoid abrupt withdrawal, concurrent ECT (lowers seizure threshold), diuretics (risk of toxicity), elderly, epilepsy, myasthenia gravis, psoriasis, QT interval prolongation
CI: Addison’s, cardiac disease, dehydration, Brugada syndrome FHx, low na+ diet, hypothyroidism
Interactions: lots! levels required every 6 months
Sodium valproate
Mood stabiling anticonvulsant
Use: seizure prophylaxis in epilepsy, established status epilepticus, bipolar disorder (acute treatment of manic episodes)
MOA: weak inhibitor of neuronal Na+ channels, stabilising the rest membrane potentials and reducing neuronal excitability. Increases the content of GABA.
Adverse effects: GI upset (nausea, gastric irritation, diarrhoea), neurological upset (tremor, ataxia, behaviour disturbance), thrombocytopenia, transient increase in liver enzymes, hypersensitivity reactions (hair loss)
Cautions: hepatic impairment and severe renal impairment
CI: women of childbearing age, T1 of pregnancy
Interactions: increases plasma conc. and risk of toxicity of lamotrigine and drugs metabolised by CYP450 (warfarin). Conc. reduced by CYP inducers (carbamazepine, phenytoin) and increased by CYP inducers (macrolide, protease inhibitors). Efficacy is reduced in those that lower the seizure threshold (antipsychotics, tramadol).
Atypical antipsychotics
E.g. Risperidone, olanzapine, clozapine, quetiapine
Use: psychomotor agitation, schizophrenia, bipolar
MOA: block post-synaptic D2 receptors. Higher affinity for other receptors (particularly 5HT2a). More efficacious in treatment-resistant schizophrenia (compared to typical) and negative symptoms, and less risk of EPSEs.
Adverse effects: sedation, weight gain, DM, QT prolongation, breast symptoms, sexual dysfunction, EPSEs, agranulocytosis (clozapine)
Cautions: CVD
CI: severe heart disease or hx of neutropenia
Interactions: do not combine with DA-blocking antiemetics and drugs which prolong QT interval (SSRIs, macrolide, amiodarone, quinine)
Aripiprazole
Atypical antipsychotic
Use: schizophrenia, mania
MOA: 5HT2, D2, alpah1 and 2, H1 agonist
Adverse effects: anxiety, appetite, DM, GI discomfort, headache, hypersalivation, nausea, vision
Cautions:
CI: CNS depression, coma, phaeochromocytoma
Interactions:
