2. PROPERTIES OF ARSENIC (AS)
It is a heavy metallic inorganic irritant poison
Inorganic arsenic compounds are poisonous:
Arsenic trioxide, sodium arsenite, arsenic sulphide,
copperarsenite, etc.
Metallic arsenic is non poisonous if ingested
because it is not absorbed
3. MECHANISM OF ACTION
Arsenic ion binds with sulphydryl group (-SH) of
enzymes in the liver, lungs, intestinal walls,
spleen
It replaces phosphorus in bones where it may
remain for years
It also gets deposited in the hairs
4. SIGNS & SYMPTOMS
Arsenic poisoning clinically manifests in three
forms 1. ACUTE FULMINATING TYPE:
•
Symptoms occur within half an hour when
heavy dose (3-5 gm) is taken
•
Acts on sulphhydryl groups of enzymes and
capillaries inhibiting cellular metabolism and
causing marked dilation of capillaries and
myocardial failure resulting in shock and
death
5. 2.SUB ACUTE TYPE( GASTROENTERITIS TYPE):
• When small doses of arsenic are given at repeated intervals
• Resembles case of cholera or food poisoning
Arsenic poisoning
Cholera
Vomiting precedes purging
Purging precedes vomiting
Stools are rice water
initially and later turn
bloodstained
Stools are rice water
throughout and passed as
involuntary jet
Pain in the throat
No pain in the throat
Voice remains unaffected
Voice rough & whistling
Conjunctiva is inflamed
Conjunctiva is normal
Vomitus contains mucus,
bile and streaks of blood
Vomitus is watery
6. 3. CHRONIC TYPE:
Presents with a sequence of 5 different set of manifestations
Gastrointestinal: presents with gradual weight loss,
malnutrition, fatigue, loss of appetite
Catarrhal changes: presents with running nose,
headache, conjunctivitis, bronchial catarrh
Raindrop pigmentation: known to produce milk & roses
complexion initially, followed by patchy brown
pigmentation of the skin (especially forehead, neck,
shoulders)
7. 3. CHRONIC TYPE:
It might also show hyperkeratosis of the skin of
palms and soles
Mees lines: whitish lines 1-2 mm breadth across the
nails of fingers and toes
Arsenical neuritis: polyneuritis, optic neuritis,
paresthesias, atrophy of extensors resulting in wrist
and foot drop
Diagnosis: urinary As level of > 100 mg/24 hrs.
Blood levels are not reliable
8. TREATMENT
Butter and greasy substances act as demulcents
Gastric lavage with warm water or freshly prepared
hydrated ferric oxide solution
Hemodialysis is the line of choice in massive arsenic
poisoning
BAL is the specific antidote. (3 – 5 mg/kg 4 hourly deep
IM for 2 days followed by 2 – 3 mg/kg 6 hourly for 2
days and then every 12 hours for 7 days)
DMSA, Penicillamine can also be used
Symptomatic therapy
Inj. Vitamin B1 helps in peripheral neuritis
9. POSTMORTEM FINDINGS
Stomach: velvety red or brownish, patchy areas
with ulceration. Gastric contents emit garlicky odor
Heart: subendocardial haemorrhage
Other viscera: fatty degeneration of liver, kidney &
heart
Brain may show inflammation with haemorrhagic
spots
10. MEDICOLEGAL IMPORTANCE
It was considered as an ideal homicidal poison as it
was Cheap
Easy to obtain
Could be easily mixed and given
Symptoms were similar to cholera
Accidental poisoning with those who consume for its
aphrodisiac effects
Accidental poisoning with contaminated tube well
water is common in Asia