Hello buddies!!! Its Vishnu..back again , with my 17th ppt... This time, its regarding BARBITURATE POISONING....which is of relevance in the subject CLINICAL TOXICOLOGY, studied in 4th year............ It includes all the required details for BARBITURATE POISONING....Along with fatal doses, and management strategies............. This will be of help for reading and reference , and also for 4th year students................... THANKS FOR READING!! DO KEEP SENDING UR REVIEWS!! Regards and love, rxvichu-alwz4uh! :) :)

1. BARBITURATE POISONING: A
PRECISE INSIGHT
PRESENTED BY :
VISHNU.R.NAIR,
4TH YEAR PHARM.D,
NATIONAL COLLEGE OF PHARMACY (NCP),
KERALA UNIVERSITY OF HEALTH SCIENCES
(KUHS), KERALA STATE.

2. INDEX/ CONTENTS OF THIS
PRESENTATION :
GENERAL ACKNOWLEDGEMENT 
DEFINITION OF BARBITURATES 
CLASSIFICATION OF BARBITURATES
MECHANISM OF ACTION AND TOXICITY
GENERAL USES OF BARBITURATES 
TOXICOKINETICS 
ADVERSE EFFECTS OF BARBITURATES 
TOXIC EFFECTS OF BARBITURATES
USUAL FATAL DOSES
POSTMORTEM APPEARANCES
TREATMENT OF BARBITURATE POISONING 

3.  GENERAL ACKNOWLEDGEMENT  :
• “NOTHING IS IMPOSSIBLE, UNLESS U RESOLVE TO GO FOR
IT”- ANONYMOUS
• THIS IS MY 17TH PPT OVERALL…AND 2ND ON TOXICOLOGY
• THANKING MY TOXICOLOGY TEACHER, AND MANY OTHER
TEACHERS, FOR HER GUIDANCE ON MAKING NOTES AND
REFERENCE , AND EMOTIONAL SUPPORT
• THANKING THE ALMIGHTY FOR EVERLASTING BLISS AND
LOVE
• THANKING MY PARENTS, COUSINS, FRIENDS(MY CLASS
,WATSAPP PHARM.D GROUP) , WELL-WISHERS AND

4.  DEFINITION OF BARBITURATES  :
“ DERIVATIVES of BARBITURIC ACID,
used as SEDATIVE-HYPNOTICS , and
also for the treatment of
EPILEPSY”………………

5.  CLASSIFICATION OF BARBITURATES  :
1. ULTRA-SHORT ACTING BARBITURATES :
- Duration of action: >0.5 hours
- Examples include:
a. THIOPENTAL
b. METHOHEXITAL
2. SHORT-ACTING BARBITURATES:
- Duration of action : >3-4 hours
- Examples include:
a. PENTOBARBITAL b. SECOBARBITAL

6. 3. INTERMEDIATE-ACTING BARBITURATES:
- Duration of action : >4-6 hours
- Examples include:
a. AMOBARBITAL
b. APROBARBITAL
c. BUTABARBITAL
d. BUTALBITAL
4. LONG-ACTING BARBITURATES:
- Duration of action: >6-12 hours
- Examples include:
a. MEPHOBARBITAL
b. PHENOBARBITAL…………………

7.  MECHANISM OF ACTION & TOXICITY  :
• BARBITURATES  Causes GENERALIZED DEPRESSION of neuronal activity in
brain
• DRUG  Interacts with BARBITURATE RECEPTOR  Leads to increase in
GABA-MEDIATED CHLORIDE CHANNEL CURRENTS  Causes SYNAPTIC
INHIBITION
• DRUG  also depresses CENTRAL SYMPATHETIC TONE & CARDIAC
CONTRACTILITY  Leads to HYPOTENSION……………………….

8.  GENERAL USES OF BARBITURATES  :
1. SEDATIVE-HYPNOTIC
2. PRE-OPERATIVE SEDATION
3. GTCS
4. FEBRILE CONVULSIONS
5. STATUS EPILEPTICUS

9.  TOXICOKINETICS  :
1. ORAL ROUTE  Preferred for SEDATIVE-HYPNOTIC action
2. I.V ROUTE  Preferred for :
a. STATUS EPILEPTICUS management
b. Induction/ maintenance of GENERAL ANAESTHESIA
3. Distributed widely
4. Undergoes HEPATIC OXIDATION to form metabolites , like:
A. ALCOHOLS
B. KETONES
C. PHENOLS
D. CARBOXYLIC ACIDS
5. Excreted as such in URINE/ as GLUCURONIC ACID conjugates…………………………

10.  ADVERSE EFFECTS OF BARBITURATES  :
1. RESIDUAL DEPRESSION (After the main effect of the drug ceases)
2. PARADOXICAL EXCITEMENT (especially in elderly)
3. HYPERSENSITIVITY REACTIONS :
- include:
A. Localized swelling of eyelid, lips or cheeks
B. Erythematous or exfoliative dermatitis

11.  TOXIC EFFECTS OF BARBITURATES  :
1. Slurred speech
2. Ataxia
3. Lethargy
4. Confusion
5. Headache
6. Nystagmus
7. CNS depression
8. ComA
9. Shock
10.Constricted pupils

12. 11. Hypothermia
12. Cutaneous bullae (blisters)
13. Respiratory arrest or CV collapse…………………
FOR MILD-MODERATE INTOXICATION:
- SLURRED SPEECH - ATAXIA - NYSTAGMUS
FOR HIGHERDOSES:
- HYPOTENSION - RESPIRATORY ARREST - COMA
- HYPOTHERMIA

13.  USUAL FATAL DOSES  :
1.FOR PHENOBARBITONE :
6-10 GRAMS
2. FOR AM0BARBITAL, SECOBARBITAL, PENTOBARBITAL:
2-3 GRAMS………………..

14.  POSTMORTEM APPEARANCES  :
1. PERIPHERAL CYANOSIS
2. FROTH AT MOUTH AND NOSE
3. BARBITURATE BLISTERS , PRESENT ON:
- Buttocks
- Calves
- Forearms
4. HIGHLY CONGESTED LUNGS
5. STOMACH EROSION………………..

15.  TREATMENT OF BARBITURATE
POISONING  :
- There is no specific ANTIDOTE for BARBITURATE POISONING
- EMERGENCY & SUPPORTIVE MEASURES:
Include:
a. AIRWAY PROTECTION
b. ASSISTED VENTILATION(IF NECESSARY)
c. Treat COMA, HYPOTHERMIA and HYPOTENSION if they occur
d. For COMA, focus on the following treatment principles:
* DEXTROSE : For ADULTS (50% solution, 50 ml. I.V), for CHILDREN (25% solution, 2
ml/kg I.V)
• THIAMINE : 100 mg (I.V)
• NALOXONE : Initially 0.4 mg I.V  If no response to therapy  give 2 mg I.V  if
no response to therapy  give 10-20 mg I.V

16. E. For HYPOTHERMIA, focus on the following treatment principles:
• If patient is not in CARDIAC ARREST  REWARM SLOWLY , using BLANKETS,
WARM I.V FLUIDS
• If patient is in CARDIAC ARREST  Use GASTRIC/ PERITONEAL LAVAGE with
WARM FLUIDS , and perform CPR
• For VENTRICULAR FIBRILLATION  Use BRETYLIUM (5-10 mg I.V)
• Perform OPEN CARDIAC MASSAGE/ PARTIAL CARDIOPULMONARY BYPASS
under non-responsiveness of the above measures………………………..
F. For HYPOTENSION, focus on the following treatment principles:
• Use I.V FLUIDS/ LOW DOSE PRESSORS(DOPAMINE)
• Focus on PATIENT REWARMING
• FLUID CHALLENGE CONCEPT: Use NORMAL SALINE(10-20 ml/kg) / any
other CRYSTALLOID SOLUTION

17. • Give DOPAMINE (5-15 mcg/kg/min)
• If above measures are not effective  insert CENTRAL VENOUS PRESSURE (CVP)
MONITOR/ PULMONARY ARTERY CATHETER , to check :
1. If fluids are required
2. CARDIAC OUTPUT and SYSTEMIC VASCULR RESISTANCE, according to the
formula:
SVR= [80(MAP-CVP)]/ CO,
Where
MAP = MEAN ARTERIAL PRESSURE
CVP = CENTRAL VENOUS PRESSURE
• Normal value of SVR : 770-1500
• If CVP is low  give more IV FLUIDS
• If CO is low  give DOBUTAMINE/ DOPAMINE
• If SVR is low  give NOREPINEPHRINE (4-8 mcg/min)

18. G. Intubation
H. SUPPLEMENTAL OXYGEN
- DECONTAMINATIONPRINCIPLES:
1. FOR PRE-HOSPITAL DECONTAMINATION : Give ACTIVATED CHARCOAL (If
available)
2. FOR IN- HOSPITAL DECONTAMINATION :
- Give ACTIVATED CHARCOAL
- Focus on GASTRIC LAVAGE (In cases of MASSIVE INGESTION of BARBITURATES)
- ENHANCED ELIMINATION:
1. URINE ALKALINIZATION (Only for PHENOBARBITAL)
2. REPEAT DOSE ACTIVATED CHARCOAL (Only for PHENOBARBITAL)
3. HAEMODIALYSIS & HAEMOPERFUSION (In patients, not responding to SUPPORTIVE
CARE)…

19.  BIBLIOGRAPHY/ REFERENCE  :
1. ALBERTSON.E.T; “BARBITURATES”; “POISONING AND
DRUG OVERDOSE BY KENT.R.OLSON” ; 4TH EDITION;
MCGRAW HILL PUBLICATIONS; PAGE: 124-126
2. “ALCOHOLS & SEDATIVES: BARBITURATES”;
“TEXTBOOK OF FORENSIC MEDICINE& TOXICOLOGY
BY DR.V.V.PILLAY”; 17TH EDITION; PARAS MEDICAL
PUBLISHERS; PAGE: 598-599………………………

20. THANK YOU!!
THANKS FOR
READING!!
@ RXVICHU-