Psychopharmacology

Psychopharmacology

Aashish PariharLecturer

College Of NursingAIIMS, Jodhpur

• Psychopharmacology is the study of the effects of drugs on affect, cognition, and behavior• Efficacy refers to the maximal therapeutic that a drug can achieve.• Potency describe the amount of the drug needed to achieve the

maximum effect. • Half life is the time taken for half of the drug to be removed from the

blood stream.• Agonist a drug that binds to and activates a receptor • Antagonist a drug that binds to but does not activate (block) a

receptor

Psychopharmacology

• Neurotransmitters are the chemical messengers that travel from one brain cell to another and are synthesized by enzymes from certain dietary amino acids or precursors

Receptors are molecules situated on the cell membrane that are binding sites for neurotransmitters.

Psychopharmacology

Psychopharmacology

Drug Action on Synaptic Transmission

Psychopharmacology

Agonist drugs are in red, Antagonists are in blue

Presynaptic Drug Actions• Presynaptic autoreceptors regulate the amount of NT released from

the axon terminal• Drugs that activate presynaptic autoreceptors reduce the amount of NT

released, an antagonistic action• Drugs that inactivate presynaptic autoreceptors increase the amount of NT

released, an agonistic action

• Presynaptic heteroreceptors are sensitive to NT released by another neuron, can be inhibitory or facilitatory

Psychopharmacology

Effect of drug in neurotransmission• Release• Blockade• Changes in receptor sensitivity• Blocked reuptake• Interference with storage vesicles• Precursor chain interference

Psychopharmacology

Classifications of psychotropic drugs• Antipsychotics • Antidepressants• Mood stabilizing agents• Anxiolytics• Antiepileptic drugs• Antiparkinsonian drugs• Miscellaneous (stimulants, drugs used for de addiction, drugs used in child psychiatry)

Psychopharmacology

Antiparkinsonian drugs

Antiparkinsonian drugs• Classification of antiparkinsonian Drugs:• Drugs acting on dopaminergic system:• Dopamine precursors – Levodopa (l-dopa)• Peripheral decarboxylase inhibitors – carbidopa and

benserazide• Dopaminergic agonists: Bromocriptyne, Ropinirole and

Pramipexole• MAO-B inhibitors – Selegiline, Rasagiline• Dopamine facilitator - Amantadine

• Drugs acting on cholinergic system• Central anticholinergics – Teihexyphenidyl (Benzhexol),

Procyclidine, Biperiden• Antihistaminics – Orphenadrine, Promethazine

Antiparkinsonian drugs• Dopamine and Tyrosine Are Not Used for Parkinson Disease

Therapy, Why?

–Dopamine Doesn't Cross the Blood Brain Barrier

–Huge amount of tyrosine decreases activity of rate limiting enzyme Tyrosine Hydroxylase

Antiparkinsonian drugs• Levodopa

• Single most effective agent in PD• Inactive by itself but immediate precursor of Dopamine• Peripherally - 95% is decarboxylated in peripheral tissues in gut

and liver to dopamine– This dopamine acts on peripheral organs like heart, blood vessels

and CTZ etc. (NOT CNS)• 1 - 2% crosses BBB, taken up by neurons and DA is formed– Stored and released as neurotransmitter

Antiparkinsonian drugs• Levodopa• Actions of Levodopa – CNS• Effective in Eliminating Most of the Symptoms of Parkinson Disease

(initially motor)– Bradykinesia and Rigidity Respond Quickly – Reduction in Tremor Effect with Continued therapy

• Secondary symptoms - Handwriting , speech, facial expression and interest in life improves gradually

• L -Dopa less Effective in Eliminating Postural Instability and Shuffling Gait Meaning Other Neurotransmitters are Involved in Parkinson Disease

• Behavioural Effects:– Partially Changes Mood by elevating mood, and increases

Patient sense of well being - General alerting response– Disproportionate increase in sexual activity– No improvement in dementia – psychiatric symptoms

Antiparkinsonian drugs• Levodopa• Actions of Levodopa –CVS:–Cardiac Stimulation Due to Beta adrenergic effect on Heart –Though stimulates peripheral adrenergic receptor – no rise in

BP –Orthostatic Hypotension - some individuals – central DA and

NA action– In elderly cardiovascular problems - transient tachycardia,

cardiac arrhythmias and hypertension–Tolerance to CVS action develops within few weeks

• CTZ: DA receptors cause stimulation – nausea and vomiting – tolerance• Endocrine: Decrease in Prolactin level and increase in GH

release

Antiparkinsonian drugs• LevodopaPharmacokinetics• Absorbed rapidly from small intestine • High First Pass Effect– Competition for amino acids present in food competes for the carrier– Also depends on gastric emptying and pH

• Peak plasma conc. 1-2 hrs. and half life - 1 to 3 Hrs• Metabolized in liver and peripherally - secreted in urine unchanged or conjugated

with glucoronyl sulfate• Central entry into CNS (1%) - mediated by membrane transporter for aromatic

amino acids – competition with dietary protein• In CNS – Decarboxylated and DA is formed – therapeutic effectiveness• Transport back by presynaptic uptake or metabolized by MAO.

Antiparkinsonian drugs• LevodopaPharmacokinetics

Antiparkinsonian drugs• LevodopaADRs

• Initial Therapy:Nausea and vomiting - 80% of patients Postural hypotension , but asymptomatic : 30 % of patients tolerance

develops – disappear after prolonged treatmentCardiac arrhythmias (due to beta adrenergic action and peripheral CA

synthesis) - tachycardia, ventricular extrasystoles and, rarely, atrial fibrillationExacerbation of angina


• Prolonged therapy:1. Abnormal movements: Facial tics, grimacing, tongue thrusting,

choreoathetoid movements of limb after few months of treatment2. Behavioural effects:– 20 to 25% of Population– Trouble in Thinking (Cognitive Effects)– L- dopa can induce: Anxiety, psychosis, confusion, hallucination, delusion– Hypomania - Inappropriate Sexual Behavior; "Dirty Old Man", "Flashers“

- Drug Holiday (1 - 3 weeks)


• Prolonged therapy – contd :Fluctuation in Motor Performance:

Initial therapy – each dose - good duration of action 9more than half-life)Suggesting Nigrostriatum retains capacity to store and release

Prolonged therapy – “buffering” capacity is lost – each dose causes fluctuation of motor state - each dose has short duration of action– short therapeutic effect (1 – 2 Hrs) – bradykinesia and rigidity comes back quickly - "On-off" Phenomenon

Like a Light Switch: Without WarningDYSKINESIA – excessive abnormal involuntary movements even in on phase

(more troublesome)Dyskinesia often with high plasma conc. of levodopaDyskinesia = Bradykinesia and Rigidity in terms of patient comfortness

Antianxiety drugs• Anti-anxiety medications, as the name implies, are prescribed to

reduce anxiety.

• They are prescribed for a number of illnesses: • Generalized Anxiety (GAD)• Post-Traumatic Stress Disorder (PTSD)• Phobias• Obsessive Compulsive Disorder (OCD)• Panic Disorder• Insomnia related to Anxiety

Antianxiety drugs• ClassificationBarbiturates:Benzodiazepines Non barbiturates and non benzodiazepines

Antianxiety drugs• Benzodiazepines are considered CNS depressants.

• How do they work? Enhance the actions of the neurotransmitter, GABA, which slows down brain activity. This produces a drowsy or calming affect.

• They are used to produce sedation, induce sleep, relieve anxiety and muscle spasms, and to prevent seizures.

Antianxiety drugs• Side Effects: drowsiness, dizziness, loss of coordination, fatigue,

mental slowing, confusion.

• Withdrawal reactions are possible. S/S: anxiety, shakiness, headache, dizziness, seizures.

• Precautions: with elderly, lung disease, liver disease, kidney disease, sleep apnea

• Contraindications: acute narrow angle glaucoma

Antianxiety drugs• Safety Concerns: • risk of addiction: should be only used short term.• Patient should not drive or operate heavy machinery.• Not to be mixed with ETOH, opiates, OTC cough/allergy medications, dental

anesthetics – can be life threatening (resp. depression)• Discuss use of OTC medications and supplements and other prescribed drugs

with MD before taking them with this type of medication.• MUST NOT be discontinued abruptly. Taper schedule is prescribed.

Antipsychotic drugsSynonymous

•Neuroleptic drugs

• Anti-schizophrenic drugs

•Major tranquilizers

•Dopamine receptor antagonists

Antipsychotic drugsClassification:TYPICAL ANTIPSYCHOTICSa. Phenothiazine derivatives• Aliphatic Derivative: CHLORPROMAZINE• Piperidine Derivative: THIORIDAZINE• Piperazine Derivative: FLUPENAZINE,

PERPHENAZINE, TRIFLUOPERAZINEb. Thioxanthene Derivative: THIOTHIXENEc. Butyrophenone: HALOPERIDOL

Antipsychotic drugsClassification:ATYPICAL ANTIPSYCHOTICS• CLOZAPINE LOXAPINE• OLANZAPINE QUETIAPINE• RISPERIDONE MOLINDONE• ZIPRASIDONE• SERTINDOLE ARIPIPRAZOLE

Antipsychotic drugsDifference between Typical Antipsychotics and Atypical Antipsychotics• 1. The side effects • 2. The efficacy • 3. Atypical anti psychotics are excreted faster.• 4. Atypical anti psychotics are less likely to cause extra pyramidal motor control and tardive dyskinesia • 5. Atypical anti psychotics are easier to discontinue and are less addictive.

Antipsychotic drugsDifference between Typical Antipsychotics and Atypical Antipsychotics• 6. Atypical anti psychotic drugs are recommended over typical psychotic drugs.• 7. Atypical anti psychotics fail to produce prolactin in the serum.• 8. Withdrawal symptoms are less likely with atypical anti psychotic drugs • 9. Akathesia to be less intense with these drugs than the typical antipsychotic.

Antipsychotic drugs

Antipsychotic drugsMechanism of action:(Typical Antipsychotics)

Antipsychotic drugsPharmacological action of Anti psychotic drugs:CNS-• Reduction in irrational behavior, agitation,

aggressiveness.• Disturbed thoughts and behavior gradually normalized• Relives anxiety• Hyperactivity , hallucination and delusions are

suppressed• Sedation• Lowers seizures threshold level• Extrapyramidal motor disturbances

Antipsychotic drugsPharmacological action of Anti psychotic drugs:ANS-• Exerts adrenergic blocking activity results in- postural hypotensionPalpitationInhibition of ejaculation• Exerts anticholinergic activity results in- dry mouthBlurring of visionConstipationUrinary hesitancy

Antipsychotic drugsPharmacological action of Anti psychotic drugs:CVS-• Hypotension due to adrenergic blocking action• Reflex tachycardia• Q-T prolongation and T wave suppressionEndocrine-• Increases secretion of prolactin hormone results in

gynecomastia and galactorrhea• Reduction of gonadotropin hormone results in

amenorrhea, infertility.

Antipsychotic drugsPharmacokinetics: • Most neuroleptic drugs are highly lipophilic, bind avidly to

proteins, and tend to accumulate in highly perfused tissues. • Oral absorption is incomplete and erratic.• IM injection is more reliable. With repeated administration,

variable accumulation occurs in body fat and possibly in brain myelin. • Half-lives are generally long, and so a single daily dose is

effective. • After long-term treatment and drug administration is

stopped, therapeutic effects may outlast significant blood concentrations by days or weeks. This may result from tight binding of parent drug of active metabolites in the brain.• Metabolites are excreted in urine and bile.

Antipsychotic drugsUses: : • Schizophrenia• Schizoaffective disorder• Mania• Organic brain syndrome• Anxiety• Preanaesthtic medication• Intractable hiccough• Tetanus• Alcoholic hallucination• Huntington’s disease• Tourette’s syndrome

Antipsychotic drugsContraindications:These drugs are contraindicated in •Hypersensitivity • CNS depression • Blood dyscrasias • Parkinson’s disease• Liver, renal, or cardiac insufficiency

Antipsychotic drugsPrecautions:• Elderly, severely ill, or debilitated, and to diabetic clients or clients with respiratory insufficiency, prostatic hypertrophy, or intestinal obstruction.• Individuals should avoid exposure to extremes in temperature while taking antipsychotic medication. • Safety in pregnancy and lactation has not been established.

Antipsychotic drugsAdverse drug reactions:Anticholinergic effects-• Dry mouth• Blurred vision• Constipation• Urinary retentionNausea, GI upsetSkin rashesSedationPhotosensitivity Orthostatic hypotension

Antipsychotic drugsAdverse drug reactions:Hormonal effects• Decreased libido, gynecomastia• Amenorrhea• Infertility• Weight gainECG changes• Q-T prolongation and T wave suppressionDecreased threshold level Agranulocytosis Hypersalivation

Antipsychotic drugsAdverse drug reactions: Extrapyramidal symptoms • Pseudo-parkinsonism (tremor, shuffling gait, drooling,

rigidity) • Akinesia (muscular weakness) • Akathisia (continuous restlessness and fidgeting) • Dystonia (involuntary muscular movements [spasms] of

face, arms, legs, and neck)• Oculogyric crisis (uncontrolled rolling back of the eyes)

Antipsychotic drugsExtrapyramidal symptoms • Pseudo-parkinsonism

(tremor, shuffling gait, drooling, rigidity)

Akinesia Akathisia

Antipsychotic drugsExtrapyramidal symptoms • Dystonia Oculogyric crisis

Antipsychotic drugsAdverse drug reactions: Tardive dyskinesia (bizarre facial and tongue

movements, stiff neck, and difficulty swallowing)

Antipsychotic drugsAdverse drug reactions: Neuroleptic malignant syndrome (NMS) Symptoms include -Severe parkinsonian muscle rigidity, Hyperpyrexia up to 107 f, Tachycardia, Tachypnea, Fluctuations in blood pressure,Diaphoresis, Rapid deterioration of mental status Stupor and coma.

Antipsychotic drugsNursing management of ADR:For Anticholinergic effects :• Provide the client with sugarless candy or gum, ice, and frequent sips

of water. • Ensure that client practices strict oral hygiene. • Explain that this symptom will most likely subside after a few weeks.• Advise client not to drive a car until vision clears.• Clear small items from pathway to prevent falls. • Order foods high in fiber• Encourage increase in physical activity and fluid intake if not

contraindicated. • Instruct the client to report any difficulty urinating; monitor intake and

output.

Antipsychotic drugsNursing management of ADR:For Nausea and GI upset:• Tablets or capsules may be administered with food to

minimize GI upset.• Concentrates may be diluted and administered with

fruit juice or other liquid.• They should be mixed immediately before

administration.

Antipsychotic drugsNursing management of ADR:For Skin Rash:• Report appearance of any rash on skin to physician.• Avoid spilling any of the liquid concentrate on skin• Contact dermatitis can occur with some medications.

Antipsychotic drugsNursing management of ADR:For Sedation:• Discuss with the physician the possibility of

administering the drug at bedtime.• Discuss with the physician a possible decrease in

dosage or an order for a less sedating drug.• Instruct client not to drive or operate dangerous

equipment while experiencing sedation.

Antipsychotic drugsNursing management of ADR:For Orthostatic hypotension :• Instruct the client to rise slowly from a lying or sitting

position• Monitor blood pressure (lying and standing) each shift• Document and report significant changes.

Antipsychotic drugsNursing management of ADR:For Photosensitivity:• Ensure that the client wears a protective sunblock

lotion, clothing, and sunglasses while spending time outdoors.

Antipsychotic drugsNursing management of ADR:For Hormonal effects:• Provide an explanation of the effects and reassurance of

reversibility. • If necessary, discuss with the physician the possibility of

ordering alternate medication. • Offer reassurance of reversibility• Instruct the client to continue use of contraception, because

amenorrhea does not indicate cessation of ovulation. • Weigh client every other day• Order a calorie controlled diet• Provide an opportunity for physical exercise• Provide diet and exercise instruction.

Antipsychotic drugsNursing management of ADR:For ECG Changes:• Caution is advised in prescribing this medication to

individuals with history of arrhythmias. • Conditions that produce hypokalemia and/or

hypomagnesemia, such as diuretic therapy or diarrhea, should be taken into consideration when prescribing. • Routine ECG should be taken before initiation of therapy and

periodically during therapy.• Monitor vital signs every shift.• Observe for symptoms of dizziness, palpitations, syncope, or

weakness.

Antipsychotic drugsNursing management of ADR:For Reduction of seizure threshold:• Closely observe clients with history of seizures.

Antipsychotic drugsNursing management of ADR:For Agranulocytosis:• There is a significant risk of agranulocytosis with clozapine.• A baseline white blood cell (WBC) count and absolute neutrophil

count (ANC) must be taken before initiation of treatment with clozapine and weekly for the first 6 months of treatment. • Only a 1-week supply of medication is dispensed at a time. • If the counts remain within the acceptable levels (i.e., WBC at

least 3,500/mm3 and the ANC at least 2,000/mm3) during the 6-month period, blood counts may be monitored biweekly, and a 2-week supply of medication may then be dispensed• If the counts remain within the acceptable level for the biweekly

period, counts may then be monitored every 4 weeks thereafter. • When the medication is discontinued, weekly WBC counts are

continued for an additional 4 weeks.

Antipsychotic drugsNursing management of ADR:For Hyper salivation (with clozapine) :• A significant number of clients receiving clozapine therapy

experience extreme salivation. • Offer support to the client because this may be an embarrassing

situation. • It may even be a safety issue (e.g., risk of aspiration) if the

problem is very severe.

Antipsychotic drugsNursing management of ADR:For Extrapyramidal symptoms (EPS) :• Pseudoparkinsonism (tremor, shuffling gait, drooling, rigidity) may appear 1

to 5 days following initiation of antipsychotic medication; occurs most often in women, the elderly, and dehydrated clients.

• Akathisia (continuous restlessness and fidgeting) occurs most frequently in women, symptoms may occur 50 to 60 days following initiation of therapy.

• Dystonia (involuntary muscular movements [spasms] of face, arms, legs, and neck) and oculogyric crisis occurs most often in men and in people younger than 25 years of age.

• Pseudoparkinsonism and akathisia can be treated with anticholinergics, antihistamine and dopaminergic agents.

• Dystonia and oculogyric crisis should be treated as an emergency situation. • The physician should be contacted, and intravenous or intramuscular

benztropine mesylate (Cogentin) is commonly administered. • Stay with the client and offer reassurance and support during this frightening

time.

Antipsychotic drugsNursing management of ADR:For Tardive dyskinesia :• All clients receiving long-term (months or years) antipsychotic

therapy are at risk. • The symptoms are potentially irreversible. • The drug should be withdrawn at the first sign, which is usually

vermiform movements of the tongue• Prompt action may prevent irreversibility.

Antipsychotic drugsNursing management of ADR:For Neuroleptic malignant syndrome (NMS) :• This is a rare, but potentially fatal, complication of treatment

with neuroleptic drugs. • Routine assessments should include temperature and

observation for parkinsonian symptoms.• Onset can occur within hours or even years after drug initiation,

and progression is rapid over the following 24 to 72 hours. • Discontinue neuroleptic medication immediately. • Monitor vital signs, degree of muscle rigidity, intake and output,

level of consciousness. • The physician may order bromocriptine (Parlodel) or dantrolene

(Dantrium) to counteract the effects of neuroleptic malignant syndrome

AntidepressantsIndications• Dysthymic disorder• Major depression with melancholia or psychotic

symptoms• Depression associated with organic disease, alcoholism,

schizophrenia, or mental retardation• Depressive phase of bipolar disorder• Depression accompanied by anxiety.

AntidepressantsClassification• Tricyclics• SSRIs (Selective serotonin reuptake inhibitor)•MAOIs (Mono amine oxidase inhibitors)•Others

AntidepressantsClassification• TricyclicsAmitriptyline, Nortriptyline Protriptyline Amoxapine, DoxepinClomipramine, Desipramine, Imipramine, Trimipramine

AntidepressantsClassification• SSRIs (Selective serotonin reuptake inhibitor)Citalopram, Escitalopram Fluoxetine, Paroxetine FluvoxamineSertraline

AntidepressantsClassification•MAOIs (Mono amine oxidase inhibitors)Isocarboxazid Phenelzine Tranylcypromine

AntidepressantsClassification•Others Bupropion Maprotiline Mirtazapine Trazodone Nefazodone Venlafaxine Duloxetine

AntidepressantsMechanism of action

AntidepressantsPharmacokineticsLipophiloic and protein boundHalf life long usually more than 1 dayMetabolized in liverExcreted in urine

AntidepressantsContraindications/Precautions •Hypersensitivity. •Myocardial infarction and angle-closure glaucoma. • Caution-Elderly or debilitated clients Hepatic, renal, or cardiac insufficiency. (The dosage usually must be decreased.)

Psychotic clients, prostatic hypertrophyHistory of seizures

AntidepressantsInteractions• Tricyclic antidepressantsHyperpyretic crisis, hypertensive crisis, severe seizures,

and tachycardia may occur when used with MAOIs. Additive CNS depression occurs with concurrent use of

CNS depressants. Additive sympathomimetic and anticholinergic effects

occur with use of other drugs possessing these same properties.

Increased effects of tricyclic antidepressants may occur with bupropion, cimetidine, haloperidol, selective serotonin reuptake inhibitors (SSRIs), and valproic acid.

AntidepressantsInteractions• SSRIsUse of SSRIs with cimetidine may result in increased

concentrations of SSRIs. Hypertensive crisis can occur if SSRIs are used within

14 days of MAOIs. Impairment of mental and motor skills may be

potentiated with use of alcohol. Serotonin syndrome may occur with concurrent use

of MAOIs, and other drugs that increase serotonin, such as tryptophan, amphetamines or other psychostimulants

AntidepressantsInteractions•MAOIsHypertensive crisis may occur with concurrent use of amphetamines,

methyldopa, levodopa, dopamine, epinephrine, norepinephrine, reserpine, vasoconstrictors, or ingestion of tyramine containing foods

Hypertension or hypotension, coma, convulsions, and death may occur with meperidine or other narcotic analgesics when used with MAOIs.

Additive hypotension may result with concurrent use of antihypertensives or spinal anesthesia and MAOIs.

Additive hypoglycemia may result with concurrent use of insulin or oral hypoglycemic agents and MAOIs.

Serious, potentially fatal adverse reactions may occur with concurrent use of other antidepressants, carbamazepine, cyclobenzaprine, maprotiline, furazolidone, procarbazine, or selegiline.

AntidepressantsAdverse effectsList of adverse effects with all classes of antidepressants•Dry mouth • Sedation •Nausea and GI upsets•Discontinuation syndrome

AntidepressantsAdverse effectsList of adverse effects with Tricyclics• Blurred vision • Constipation•Urinary retention •Orthostatic hypotension • Reduction of seizure threshold • Tachycardia; arrhythmias • Photosensitivity •Weight gain

AntidepressantsAdverse effectsList of adverse effects with SSRIs• Insomnia; agitation •Headache•Weight loss• Sexual dysfunction • Serotonin syndrome Symptoms include changes in mental status, restlessness, myoclonus, hyperreflexia, tachycardia, labile blood pressure, diaphoresis, shivering, and tremors.

AntidepressantsAdverse effectsList of adverse effects with MAOIs•Hypertensive crisis Symptoms of hypertensive crisis include severe occipital headache, palpitations, nausea/vomiting, nuchal rigidity, fever, sweating, marked increase in blood pressure, chest pain, and coma. • Priapism (With trazodone )•Hepatic failure (with nefazodone)

AntidepressantsHealth education/ nursing management• Treatment adherence• Use caution when driving or operating dangerous machinery• Not stop taking the drug abruptly• If taking a tricyclic, use sunblock lotion and wear protective

clothing • Report occurrence of any of the following symptoms to the

physician immediately: sore throat, fever, malaise, yellowish skin, unusual bleeding, easy bruising, persistent nausea/vomiting, severe headache, rapid heart rate, difficulty urinating, anorexia/weight loss, seizure activity, stiff or sore neck, and chest pain.

AntidepressantsHealth education/ nursing management• Rise slowly from a sitting or lying position to prevent a

sudden drop in blood pressure• Take frequent sips of water, chew sugarless gum, or suck on

hard candy • Good oral care • Not consume the following foods or medications while

taking MAOIs:Aged cheese, wine (especially Chianti), beer, chocolate, colas, coffee, tea, sour cream, beef/chicken livers, canned figs, soy sauce, overripe and fermented foods, pickled herring, preserved sausages, yogurt, yeast products, broad beans, cold remedies, diet pills. (TYRAMINE CONTAINING FOOD)

AntidepressantsHealth education/ nursing management• Avoid smoking while receiving tricyclic therapy. • Not drink alcohol while taking antidepressant therapy• Not consume other medications (including overthe-counter

medications) without the physician’s approval • Notify the physician immediately if inappropriate or

prolonged penile erections occur while taking trazodone • Establish seizure precaution especially with Bupripion

AntidepressantsHealth education/ nursing managementSerotonin syndrome • May occur when two drugs that potentiate serotonergic neurotransmission

such as tryptophan, amphetamines or other psychostimulants are used concurrently

• Most frequent symptoms include changes in mental status, restlessness, myoclonus, hyperreflexia, tachycardia, labile blood pressure, diaphoresis, shivering, and tremors.

• Discontinue offending agent immediately. • The physician will prescribe medications to block serotonin receptors, relieve

hyperthermia and muscle rigidity, and prevent seizures. • Artificial ventilation may be required. • The condition will usually resolve on its own once the offending medication

has been discontinued. • However, if the medication is not discontinued, the condition can progress to a

more serious state and become fatal

Mood stabilizing agents• Any medication that is able to decrease vulnerability to subsequent

episodes of mania or depression; and not exacerbate the current episode or maintenance phase of treatment.

Mood stabilizing agentsClassification of mood stabilizing drugs• Antimanic- Lithium carbonate• Anticonvulsants- Carbamazepine, Clonazepam, Valproic acid,

Lamotrigine, Gabapentin & Topiramate• Calcium channel blocker- Verapamil • Antipsychotics

Mood stabilizing agentsAntimanic(Lithium carbonate)

• Lithium as an antimanic drug was first discovered by FJ Cade in 1949.• Indications –Acute maniaProphylaxis for bipolar and unipolar mood disorderSchizoaffective disorderCyclothymiaImpulsivity and aggressionOthers like bulimia nervosa, trichotillomania, cluster headache,

borderline personality disorder.


Mechanism of action-• Exact mechanism is unknown, however it probably works by- accelerating presynaptic reuptake and destruction of

catecholamine.Inhibiting the release of catecholamineDecreasing postsynaptic serotonin receptor sensitivity.


Interaction-• Increased renal excretion of lithium with acetazolamide, osmotic diuretics,

and theophylline.• Decreased renal excretion of lithium with NSAIDsand thiazide diuretics. • There is an increased risk of neurotoxicity with carbamazepine, haloperidol,

or methyldopa. • Fluoxetine or loop diuretics may result in increased serum lithium levels. • Increased effects of neuromuscular blocking agents or tricyclic

antidepressants, • Use of lithium with phenothiazines may result in neurotoxicity,


Dosage-• 900-2100 mg in 2-3 divided dose.Blood lithium level-• Therapeutic level- 0.8-1.2 mEq/litre• Prophylactic level- 0.6-1.2 mEq/litre• Toxic lithium level - >2.0 mEq/litre


Pharmacokinetics-• Well absorbed orally• Neither protein bound nor metabolized• Kidney handles lithium in much same way as sodium.• Plasma half life is 16-30 hrs.


Contraindication and precaution-• Hypersensitivity• Cardiac or renal disease• Dehydration• Sodium depletion• Brain damage• Pregnancy and lactation. • Caution with thyroid disorders, diabetes, urinary retention, history of

seizures, and with the elderly


Adverse drug reaction-

• Neurological Tremors, Motor hyperactivityMuscular weakness• Renal PolydipsiaPolyuriaNephrotic syndrome• CVST-wave depression• DermatologicalAcne eruptionExacerbation of psoriasis

• GastrointestinalNausea, vomitingDiarrheaAbdominal painMetallic taste• Endocrine Abnormal thyroid functionGoiter Weight gain• OthersTeratogenicityEbstein’s anomalyToxicity in infant


Lithium toxicity-• The margin between the therapeutic and toxic levels of lithium carbonate is very

narrow. • Symptoms of lithium toxicity begin to appear at blood levels greater than 1.5 mEq/L • Symptoms include: At serum levels of 1.5 to 2.0 mEq/L: Blurred vision, ataxia, tinnitus, persistent

nausea and vomiting, severe diarrhea. At serum levels of 2.0 to 3.5 mEq/L: Excessive output of dilute urine, increasing

tremors, muscular irritability, psychomotor retardation, mental confusion, giddiness.

At serum levels above 3.5 mEq/L: Impaired consciousness, nystagmus, seizures, coma, oliguria/ anuria, arrhythmias, myocardial infarction, cardiovascular collapse.


Lithium toxicity-• Lithium levels should be monitored prior to medication administration. • The dosage should be withheld and the physician notified if the level reaches 1.5

mEq/L or at the earliest observation or report by the client of even the mildest symptom. • If left untreated, lithium toxicity can be life threatening.• The client must consume a diet adequate in sodium as well as 2500 to 3000 ml of

fluid per day. • Accurate records of intake, output, and client’s weight should be kept on a daily

basis.


Nursing management-• Take medication on a regular basis• Not drive or operate dangerous machinery • Not skimp on dietary sodium intake. • Avoid “junk” foods. • The client should drink six to eight large glasses of water each day • Avoid excessive use of beverages containing caffeine (coffee, tea, colas), which

promote increased urine output. • Notify the physician if vomiting or diarrhea occurs. • Carry a card or other identification noting that he or she is taking lithium. • Notify the physician as soon as possible if pregnancy is suspected or planned.


Nursing management-• Be aware of side effects and symptoms associated with toxicity. • Notify the physician if any of the following symptoms occur: persistent nausea and

vomiting, severe diarrhea, ataxia, blurred vision, tinnitus, excessive output of urine, increasing tremors, or mental confusion. • Refer to written materials furnished by health care providers while receiving self-

administered maintenance therapy. • Keep appointments for outpatient follow-up; have serum lithium level checked

every 1 to 2 months, or as advised by physician.

Drugs used in child psychiatryClonidine

• Used to control withdrawal symptoms from opioids, Tourette’s disorder, aggression and autism• It is an alpha 2 adrenergic receptor agonist• Dose is 0.1 mg BD• Side effects are dry mouth, dryness of eye, fatigue, irritability, sedation, dizziness,

nausea, vomiting, hypotension and constipation.

Drugs used in child psychiatryMethylphenidate (Retalin)

• Used in attention deficit and hyperkinetic disorder, narcolepsy, depressive disorder and obesity.• It is sympathomimetic drug• Dosage is 5-10 mg/day orally• Side effects are dyspepsia, weight loss, slowed growth, dizziness insomnia,

nightmares, tics and psychosis

Drugs used in child psychiatryAntabuse drugs (Disulfiram)

• It is used in the de-addiction from alcohol.• Its main effect is to produce a rapid and violently unpleasant reaction in a person

who ingests even a small amount of alcohol while taking disulfiram.• It cause flushing, headache, nausea and vomiting if a person drinks alcohol while

taking drug• One dose of disulfiram usually effective for 1-2 weeks.• Overdose can be dangerous, causing low blood pressure, chest pain, shortness of

breath and even death.

Psychopharmacology

Healthcare

Transcript of Psychopharmacology