Cptp - Poisonig Mh Misuse of Drugs

8/10/2019 Cptp - Poisonig Mh Misuse of Drugs

http://slidepdf.com/reader/full/cptp-poisonig-mh-misuse-of-drugs 1/5



PCM

1. Pathways of conjugation aresaturated and co-factors aredepleted and as such moreparacetamol is metabolised viaCYP450

2. Glutathione (GSH) becomes

depleted so cannot detoxifyNAPQI3. Toxic effects

150 mg/kg or 12gm – Fatal 75 mg/kg if malnourished

Phase 1 – 0-24 hoursNausea, vomiting, nothing

Phase 2 – 24-72 hoursRUQ pain, elevated liverenzymes, prolonged PT

Phase 3 – 72-96 hoursHepatic necrosis,encephalopathy, coagulopathy,ATN

Phase 4 – 4 days- 2 weeksIf damage is not irreversible,complete resolution of hepaticdysfunction will occur

GI DECONTAMINATION1. Induce Emesis /Gastric Lavage2. Activated Charcoal

SPECIFIC ANTIDOTEN-Acetyl Cysteine (NAC) – 150

mg/kg IV Infusion over 15 Minutesfollowed by the same dose IV overnext 20 hours

Acetylsalicylicacid (Aspirin)

Methylsalicylate (Oil

ofWintergreen)

Inhibition of cyclooxygenaseresults in decreased synthesis ofProstaglandins, Prostacyclin, andThromboxanes

Stimulation of the CTZ in themedulla causes nausea and

vomiting CNS Direct toxicity Activation of the respiratory

center of the medulla results intachypnea, hyperventilation,respiratory alkalosis

Uncoupled oxidativephosphorylation in themitochondria generates heat andmay increase body temperature

Interference with cellular

metabolism leads to metabolicacidosis

Mild Toxicity - 150 mg/kg Moderate Toxicity – 250 mg/kg Severe Toxicity - > 500 mg/kg Fatal - > 700 mg/kg

MILD - MODERATE Fever Tinnitus Vertigo Nausea & Vomiting

Diarhoea Dehydration Hyperventilation

SEVERE Haemorrhages Hallucinations Hyper/Hypoglycaemia Pulmonary edema Convulsions Coma

Death

Symptomatic & Supportive IV fluids

1.26% Sodium Bicarbonate Alkalinization of Urine (If Plasma

Salicylate level - > 500mg/L) Hemodialysis(If Plasma Salicylate

level - > 700mg/L)

Morphine 50 mg of Morphine IM produces

toxicity in Non-tolerant adult Fatal Dose – 250 mg

Cyanosis Pin point pupil Shallow breathing Stupor Flaccidity Hypotension Convulsions

Respiratory Support IV fluids & Vasopressors Gastric Lavage with Potassium

permanganate Specific Antidote – Naloxone 0.4

– 2 mg IV repeat every 2 minutesuntil breathing is adequate



Coma Death due to Respiratory

paralysis

Iron Most common in infants and

children

60mg/kg iron causes serious toxicity Haemorrhage Hepatic necrosis Brain damage

Induce Emesis / Gastric lavageSpecific TherapyIron chelating agent Desferrioxamine

15 mg/kg/hr IV InfusionMax – 80 mg/kg/day

TCA

Inhibition of Presynapticneurotransmitter reuptake-Noradrenaline & Seratonin Cardiac fast sodium channels Central and peripheral

muscarinic acetylcholinereceptors

Peripheral alpha-1 adrenergicreceptors

Histamine (H1) receptors CNS GABA-A receptors

Three major toxic syndromes of TCAPoisoning1. Anticholinergic effects2. Cardiac toxicity3. CNS toxicity (sedation and

seizures)Death in TCA overdose is usually dueto CNS and Cardiotoxic effects.Anticholinergic Syndrome

Hot as hell Blind as a bat Dry as a bone

Mad as a hatter

Supportive ABC ECG monitoring

GI Decontamination If patients are alert and co-

operative and have ingested > 5mg/kg, charcoal may beadministered orally

If the patient is unconscious andrequires intubation to protectthe airway insert an orogastrictube, aspirate stomach contentsthen give activated charcoal

Seizures Diazepam 5-20 mg IVPhenobarbitone 15-18 mg/kg IVPhenytoin should be avoided (

sodium-channel blocking)Anticholinergic delirium

Mild delirium can often bemanaged with reassurance plusor minus benzodiazepines

Neuroleptics should be avoided(most of which have significantanticholinergic activity)

BDZ MILD: Drowsiness , Ataxia , COMA 1 (Stage 1): Responsive to SUPPORTIVE PROCEDURES &



Weakness MODERATE TO SEVERE :Vertigo ,

slurred speech, nystagmus,partial ptosis, lethargy ,hypotension, respiratorydepression, coma (stage 1 & 2 ).

painful stimuli but not to verbal ortactile stimuli, no disturbance inrespiration or BP.COMA 2 (Stage 2):Unconscious, notresponsive to painful stimuli, nodisturbance in respiration or BP.

SYMPTOMATIC / SPECIFICTREATMENT:

Airway , breathing & circulation. IV fluid administration. Endotracheal intubation. Assisted ventilation.

DECONTAMINATION: Stomach wash within 6-12 hrs. Activated charcoal. Emesis is contraindicated.

SPECIFIC ANTIDOTE Flumazenil –reversing the coma

induced by benzodiazepines. Mode of action – competitive

antagonism. Complete reversal of

benzodiazepine effect with atotal slow iv dose of 1mg.

Administered in a series ofsmaller doses beginning with 0.2mg & progressively increasingby 0.1- 0.2 mg every minute untila cumulative total dose of 3.5mg is reached.

Organophosphorus

Generally manifests in minutes tohoursEvidence of cholinergic excessSLUDGE = Salivation,

Lacrimation,Urination,Defecation,Gastric Emptying.

BBB = Bradycardia,Bronchorrhea,

Bronchospasm.

Respiratory insufficiency canresult from muscle weakness,

decreased central drive,increased secretions, andbronchospasm and it is theleading cause of death.

Cardiac arrhythmias, includingheart block and QTc prolongatio

Termination of exposure byremoval of contaminatedclothes, washing of skin

Gastric lavage. Maintenance of patent airway

Artificial respiration Intravenous fluids

Specific Antidotes(a) Inj.atropine 2mg iv (every 10 mintill signs of atropinization appears)(b) Inj.pralidoxime 1-2g iv (children20-40 mg/kg)



MENTALHEALTH

MOA INDICATION ADVERSE EFFECTS

SSRI– FLUOXETINE

SertralineCitalopramMirtazapine

Inhibit serotonin reuptake. Increasedconcentrations of the neurotransmitter in thesynaptic cleft and ultimately, to greaterpostsynaptic neuronal activity.

Depression, OCD, PTSD, Panic disorder,generalised anxiety disorder, premenstrualdystrophic disorder, bulimia nervosa (fluoxetine)

Nausea, sleep disturbance, sexual dysfunction,drowsiness, drug interaction

Mirtazapine – weight gain + sedation

TCA– AMITRIPTYLINE

Inhibits neurotransmitter reuptake.Blocking of receptors

Moderate to severe depression. Panic disorder.Migraine, chronic pain syndrome.

Blurred vision, dry mouth, urinary retention,sinus tachycardia, constipation, and aggravationof narrow-angle glaucoma.

SNRI -VENLAFAXINE

Inhibits NA reuptake and mild inhibitor ofdopamine reuptake at high doses.

DepressionNausea, headache, sexual dysfunction,constipation, sedation, insomnia, dizzy

1st generation -HALOPERIDOL

Competitive inhibitor of D2 dopamine receptors.

4. Schizophrenia5. Severe N&V6. Agitated and disruptive behaviour

Movement disorder. High potential of EPSDid not ameliorate “negative” symptoms

2nd generation – OLANZAPINERisperidoneQuetiapineAripiprazoleClozapine

Dopamine receptor-blocking activity in the brainand periphery.Serotonin receptor-blocking activity in the brain,particularly 5-HT2A receptors

EPS – dystonias, akathisias (x leh duduk diam,nak jalan je), bradykinesia, rigidity, tremor,tardive dyskinesia

Cptp - Poisonig Mh Misuse of Drugs

Documents

Transcript of Cptp - Poisonig Mh Misuse of Drugs