Toxicology 4

toxicology is a very important topic for pg entrance.....so all about it has been discussed in detail as required for pg entrance....do make use of it...

1. -DR.AKIF A.B

2. 1. All are features of Cocaine intoxication EXCEPT:
ATactile hallucinations
BPinpoint pupil
CRestlessness
DTachycardia and tachypnoea

3. Ans. BPinpoint pupil
Cocaine poisoning
Q
-
tactile hallucinations (Magnan'ssymptoms = Cocaine bugs),
visual hallucinations,
black staining of tongue & teeth,
ulceration of the nasal septum due to sniffing,
dilated pupils : Since cocaine acts by increasing epinephrine/dopamine which
are sympathomimeticsand sympathomimeticsdilates pupil.

4. -CNS Stimulant
-Mech. ; Dopamine/Serotonin/Nor epinephrine
-Vasoconstrictor
-Derives from leaves of erythoxylumcocca
-Tactile hallucinations: also k/a Cocaine bugs/magnanbugs
-Paranoid delusions : is the fixed, false belief that one is being
harmed or persecuted by a particular person or group of people.
-If sniffed can cause Nasal septum perforation
-On oral intake : Black jet tongue
-Antidote = Amyl Nitrate

6. COCAINE ORAL INTAKE
Black Jet Tongue /Teeths

7. 2. Dhaturacauses intoxication when there is intake of:
ASeeds
BFlowers
CLeaves
DResinous intake

8. Ans. ASeeds
Dhaturafastuosa-
Fatal dose = 0.6 –1 gm (100 –120 seeds),
Fatal period = 24 hrs.

9. -Principle : Hyoscine/Atropine/Hyoscyamine/Scopola
-So all anti-cholinergic effects are seen
-Lethal Dose = 100-125seeds
-Seeds resembles chilly seeds
Antidote: Physostigmine/Pilocarpine

10. DATURA SEEDS
CHILLY SEEDS

11. 3.Q. All are features of Acute Morphine poisoning EXCEPT:
APin point pupil
BRespiratory depression
CHyperpyrexia
DFall in blood pressure

12. Ans. CHyperpyrexia
Opium poisoning
-if taken by mouth, symptoms begin in ½ hr,
-if taken by inj. Symptoms begin in 3-4 minutes.
1.Stage of excitement-sense of well-being, talkativeness, restlessness,
flushing.
2. Stage of Stupor-headache, n, v, tiredness, drowsiness, contracted pupils,
cyanosis, itching.
3. Stage of Coma-deep coma, flaccidity of muscles, pupils pin-point,
no secretions except sweat, skin cold,
temperature-subnormal, pulse slow, breathing slow,
Cheyne-Stokes respiration.

13. 4.Q. Cyanide poisoning occurs due to:
AInhibition of transmission at myoneuraljunction
BInhibition of cellular respiration
CCombination with sulphydrylradical of tissue enzyme
DInterfering with calcium metabolism

14. Ans. BInhibition of cellular respiration
Cyanides/HCN
Q
-↓ cytochromeoxidase, carbonic anhydrase,
thus blocks the final step of oxidative phosphorylationand prevents the
formation of ATP.
It reduces oxygen carrying capacity of the blood by combining with the Ferric
iron.

15. HYDROCYANIC ACID
-Also k/a Prussic Acid
-Derived from Linseed Plant
-Bitter almond smell
-Inhibits enzymes of respiratory chain : 1) Carbonic anhydrase
2) superoxide dismutase
3) Cytochromeoxidase
4) Succinatedehydrogenase
-Rx: Amyl Nitrite
+
Vit. B12
+
Na. Thiosulphate
Triple Antidote
Amyl nitrite + CN = Meth-Hb
Vit.B12 + CN = Cyanocobalamine
Na.thiosulphate+CN= Thiocyanate

16. 5.Q.Gastric lavageis contraindicated in all EXCEPT:
AComatose patient
BSulphuricacid poisoning
COxalic acid poisoning
DStrychnine poisoning

17. Ans. COxalic acid poisoning
C/I
Absolute-corrosive poisons except oxalic acid
Relative-Convulsions (strychnine, tetanus), coma, volatile poisons,
esophageal varices.

18. 6.Q. Anterior horn cells are affected in:
AStrychnine poisoning
BDhaturapoisoning
CBotulism
DNone of the above

19. Ans. AStrychnine poisoning (Strychnine
Q
(Strychnosnuxvomica= kuchila)-
1.Spasm of abdominal muscles may bend the body forward
(emprosthotonus) or to the side (pleurosthotonus), action is noted in
anterior horn cells
2. convulsions affect all muscles at a time
3. consciousness is not lost
4. Brain is preserved
5. Postmortem caloricity is seen.)

20. -nuxvomica/ kuchila
-Fatal dose = 1 crushed seed or 1 mg/kg
-Principle: Brucine/strychnine
-Inhibits glycinewhich is a inhibitory neurotransmitter and thus
inhibition of muscles is lost and all muscles contracts simultaneously.
-Acts at anterior horn cells of spinal cord
-Resembles tetanus
-Animal poison
-Arrow poison
-Increases Libido = Aphrodisiac property

21. -Pleurosthotonus/Ophistotonus/ Emprosthotonus
-Risussardonicus
-Postmortem caloricity : Strychnine increases body temperature after death
-Post-synaptic block
-Rigor mortis : Appears early and stays for long time
Note: Anything which leads to fatigue of muscles leads to early rigor and
since strychnine increases muscle contraction leads to early fatigue.
-Antidote: Diazepam
-Alkalinisationof Urine is done.
‘Ine’ containing substances:
alkalinisationis done for
treatment

23. -Botulismis a rare and potentially fatalillnesscaused by atoxin, produced by the
bacteriumClostridium botulinum.
-Botulinuminhibits the release within the nervous system ofacetylcholine,
a neurotransmitter, responsible for communication between motor
neurons and muscle cells.
-All forms of botulism lead toparalysisthat typically starts with the muscles
of the face and then spreads towards the limbs.
-In severe forms, botulism leads to paralysis of the breathing muscles and
causesrespiratory failure.
-Honeycan contain the organism, and for this reason, honey should not be fed to
children under 12 months.
-Treatmentis with an antitoxin.
-In those who lose their ability to breathe on their own,mechanical ventilationmay be
necessary for months.

25. Pleurothotonus
Risussardonicusis a highly characteristic, abnormal, sustained
spasm of the facial muscles that appears to produce grinning.
-Also seen with tetanus.
Risussardonicus

26. 7.Q.Golden hair’ is seen in poisoning with:
AArsenic
BLead
CMercury
DCopper

27. Ans. D(Copper.) > Arsenic

28. 8.Q. Organophosphoruscompounds act by:
AInhibiting cholinesterases
BStimulating cholinesterases
CStimulating acetylcholine receptors
DStimulating acetylcholine synthesis

29. Ans. AInhibiting cholinesterases
(Organophosphates
Q
-↓ acetylcholinesterase
true cholinesterase in RBCs, nervous tissue, skeletal muscle, and
Pseudocholinesterasein plasma, liver, heart, pancreas, brain.)
Read O.P poisoning in detail.

30. 9.Q. True about Strychnine poisoning is:
AAll muscles affected at the same time
BShoulder girdle affected first
CPelvic girdle affected first
DNone of the above

31. Ans. AAll muscles affected at the same time
Strychnine
Q
(Strychnosnuxvomica= kuchila)-
-spasm of abdominal muscles may bend the body forward (emprosthotonus)
or to the side (pleurosthotonus), action is noted in anterior horn cells
convulsions affect all muscles at a time
consciousness is not lost
Brain is preserved
Postmortem caloricity is seen

32. 10.Q. Sodium bicarbonate is used for gastric lavagein poisoning with:
AMethyl alcohol
BEthyl alcohol
COxalic acid
DMorphine

33. Ans. AMethyl alcohol
Methyl alcohol
Q
-Gastric lavagewith Sod. Bicarbonate, Ethyl alcohol 50%
in dose of 1 ml/kg i.v. every 2 hrs till 5 days, serum alcohol levels maintained
at 100-150 mg% at all times,
Haemodialysis.

34. -Fatal dose = 80-120ml
Responsible for symptoms
-TOC : Hemodialysis
-Antidote : Ethanol > Fomepizole
Inhibits alcohol
dehydrogenase
-Causes Putamennecrois