Anxiolytics, Antidepressants and Antipsychotics 2

Bipolar Disorder

Manic Phase

Depressive Phase

1st line- Anti-psychotics (Haliperidol, RIsperidone, Olanzapine)

Sodium Valporate

Lithium- delayed action in acute mania

Electroconvulsive Therapy

Don't use anti-depressants and stimulants and some OTC medication such as cold remedies as they precipitate mania

Antidepressants used in combination with mood stabilizers. SSRI are less likely to result in mania compared to TCA.

Anti-psychotics used alone or with an anti-depressant. QUETIAPINE

LAMOTRIGINE- Used in severe depression

Prevent Relapse Treatment

Lithium, Valporate, Anti-psychotics (OLANZOPINE, QUETIAPINE, ARIPIPRAZOLE), CARBAMAZEPINE, LAMOTRIGINE and Anti-depressants

LITHIUM

Treatment and prophylaxis of mania, bipolar disorder, recurrent depression and self-harming behaviour

Narrow therapeutic window

Slow onset of action- usually takes 7-14 days to work

Renal excretion - kidneys

S.E- tremors, GIT, renal, coma

MOA- Mimics Na+ in tissues by entering through the Na+ channels and accumulating in the cell. It won't be pumped out through the Na+/K+ ATPase pump so there will be partial loss of K+ cell depolarisation

It inhibits IMPase which is the rate-limiting enzyme in inositol recycling. So the phosphatidyl inositol pathway is blocked and inositol phosphate is hydrolysed to free inositol

Mood stabilising drug as it can reduce both manic and depressive symptoms in bipolar disorder

Toxicity S.E- Thyroid disorders, hair loss, mild cognitive impairment, acne and weight gain

Toxicity symptoms are metallic taste, thirst from polyuria, weight gain and oedema and causes of toxicity include intentional overdose or reduced drug excretion. When conc >1.5

Patient counselling- Regular fluid intake, full compliance and regular monitoring essential and avoid crash diets

Anti-psychotics

First generation (typical) anti-psychotics

D2 receptor antagonist

To treat the positive symptoms such as hallucinations

CHLORPROMAZINE, FLUPHENAZINE, FLUPENTIXOL, HALOPERIDOL

Effect over 2-4 weeks

Depot (slow-acting) anti-psychotics are used for poor adherence such as the decanoate derivatives- haliperidol decanoate

Extrapyramidal SE- Acute symptoms such as dystonias, Parkinsons and Akathisia. Tardive Dyskinesia

Other S.E- Behavioural (apathy, inhibition of aggression, reduced initiative), Cardio (orthostatic hypotension), increased levels of prolactin, neuroepileptic malignant syndrome

Other S.E- sedation, weight gain, seizures, temperature regulation, skin problems, sexual dysfunction, blood dyscrasis and visual impairment

Second generation (atypical) anti-psychotics

Greater affinity for the serotonin receptors compared to the dopamine receptors

For the treatment of the negative symptoms

Less anti-cholinergic S.E and lower risk of cardiotoxicity

No effect on prolactin levels except for RISPERIDONE, AMISULPRIDE

OLANZAPINE and RISPERIDONE increases the risk of stroke in elderly with dementia

OLANZAPINE results in weight gain, obesity and hypertension

Also causes metabolic disorders such as diabetes, hyperlipidemia and glucose intolerance

CLOZAPINE- It is a weak D2 and marked 5-HT2, Muscarinic, alpha 1 and H1 antagonist and used with patients who are unresponsive and treatment resistant.

S.E of CLOZAPINE- Increased risk of agranulocytosis, myocarditis, intestinal obstruction and hypersalivation

Patients with schizophrenia are likely to smoke but the hydrocarbons in cigarette smoke induce the cytochrome P450 enzymes which decreases the serum levels of the anti-psychotic medication. The levels of CLOZAPINE are the most affected so when the patient stops smoking, the CLOZAPINE levels increase and so there will be an increased risk of seizures. The CLOZAPINE levels need to be monitored.