Atropine is a naturally occurring anticholinergic that blocks the effects of acetylcholine at muscarinic receptors. It is derived from plants like Atropa belladonna and Datura stramonium. Atropine has wide distribution in the body after absorption and is metabolized in the liver. It causes decreased secretions from glands, relaxes smooth muscles, increases heart rate, and can cause CNS stimulation in high doses. Adverse effects include dry mouth, blurred vision, urinary retention in elderly, and toxicity can cause hyperthermia and delirium. It is used for biliary colic, cystitis, pre-anesthesia, Parkinsonism, AV block, and urinary incontin

1. ATROPINE
DR GEETANJALI S VERMA
DR GEETANJALI VERMA

2. ANTI CHOLINERGICS
• Natural : Atropine, Scopolamine
• Semisynthetic: Homatropine, Atropine
methonitrate, Hyoscine butylbromide,
Ipratropium bromide, Tiotropium bromide
• Synthetic: Cyclopentolate, Tropicamide,
Oxybutinin, Trihexphenidyl, Glycopyrrolate
DR GEETANJALI VERMA

3. • Origin:
– Atropa belladona
– Datura stramonium
• Ester of tropic acid and tropine
• MoA
– Block muscarinic effects of Ach (competitive
antagonist)
– Do not interfere with release of Ach at cholinergic
nerve endings
– Does not distinguish between the M 1 , M 2 , and M 3
DR GEETANJALI VERMA

4. DR GEETANJALI VERMA

5. PHARMACOKINETICS
• Absorbed from the gut, parenteral sites and
mucous membranes
• Distribution: widely distributed in the body
• Metabolism: in liver (conjugation)
• 60% excretes unchanged in urine
• Effects disappear quickly within 2 Hrs except eye
• Crosses placental barrier & secreted in milk &
saliva
DR GEETANJALI VERMA

6. PHARMACODYNAMICS
SECRETIONS
• Salivary: dry mouth, difficult swallowing
• Gastric: reduces vol & total acidity
– Psychic, gastric & intestinal phases of gastric secretion
blocked partially
– Reduced secretion of mucin & gastric enzymes
• Others:
– Reduces secr in nose, mouth, pharynx, bronchi (viscid)
– Decr sweat
– No lacrimal inhibition
– Little effect on pancreatic & intestinal juices & bile
DR GEETANJALI VERMA

7. SMOOTH MUSCLE
• GI
– Reduces tone & motility (antispasmodic)
– Doesn’t interfere significantly with normal peristalsis
• Biliary tract : weak anti spasmodic
• Urinary tract: reduce tone of fundus of bladder &
enhance tone of trigonal sphincter -- uri retention
• Bronchi: relaxes musc of bronchi & bronchioles
• Uterus : -
• Eye: mydriasis (sphincter of iris & ciliary musc) –
paralysis of accomodation or cyclopegia
DR GEETANJALI VERMA

8. CVS
• Initially decreases HR – partial agonist of Ach
or stimulation of vagal nuclei
• Foll by tachy (↑ by 30-40 bpm) – blocking of
M2 ® in SA node
• Toxic doses: dilatation of cutaneous blood
vessels – atropine flush & hypotension
(depression of vasomotor center or periph
vasomotor paralysis)
DR GEETANJALI VERMA

9. CNS
• Mild stimulation of medullary vagal nuclei &
higher cerebral centres – ↓HR,↑ rate & depth
of resp
• Toxic doses: marked excitation
• Mod doses: controls tremors & rigidity in
parkinsonism
DR GEETANJALI VERMA

10. DR GEETANJALI VERMA

11. DR GEETANJALI VERMA

12. ADVERSE EFFECTS
• Due to extension of its pharma actions
– Dryness of mouth, difficult swallowing
– tachycardia
– Fever
– Constipation
– Blurring of vision, ppts glaucoma (elderly)
– Retention of urine (elderly)
– Local allergy: dermatitis, conjunctivitis, swelling of
eyelids
– Drugs causing synd of acute atropine intox: TCAs,
phenothiazines, anti histaminics
DR GEETANJALI VERMA

13. ACUTE BELLADONA POISONING
• Lethal dose: children 10-30mg, adults: 80-130mg
• Periph muscarinic blockade
– Dryness of mouth, difficult swallowing, thirst
– Tachy, palpitations
– Hyperpyrexia (inhibitino of sweating)
– Dil of pupils, blurred vision, photophobia
– Uri urgency, difficult micturition, retention
– Rash –face, neck , upper trunk
• Central actions
– Excitement, restlessness
– Motor incoord
– Slurring of speech, memory disturbance
– Confusion, hallucination, mania, delirium
– n/v, HTN
– Coma, paralysis of resp centre
DR GEETANJALI VERMA

14. • Diagnosis
Adding drop of pt’s urine in cat’s eye
pupillary dilatation
• t/t:
– Ingestion: gastic lavage
– Physostigmine 1-4mg (children 0.5-1mg) IV (pref
in CNS symp)
– Neostigmine 2-5mg sc
– Repeated at intervals of 1-2hrs
– Other symptomatic mgmt (dark room, tepid
sponging, oxygen, artificial vent, catheterisation)
DR GEETANJALI VERMA

15. PREPARATIONS
• Belladona dry extract (1%)
• Belladona tincture : dose 0.6-2ml
• Atropie sulfate 0.5 mg tab or powder 0.25-
2mg
• Atropine eye oint 1%
• Atropine sulfate inj 0.5mg in 1ml
• Atropine methonitrate (0.6% alcoholic soln in
dose 0.2-0.6mg)
DR GEETANJALI VERMA

16. USES
• GI
– Biliary colic (morphine)
– Cystitis (allay freq & urgency)
• Ocular
– Fundosc examn
– Acute iritis
– Iridocyclitis
– Keratitis
DR GEETANJALI VERMA

17. • Pre anesth med:
– Reduce secretions
• OP poisioning
• Parkinsonism
• CVS: AV block, hypersensitive carotid sinus
(counters syncope & brady)
• Uri incontinence
DR GEETANJALI VERMA

18. CONTRAIND
• Age > 40yrs (acute congestive glaucoma)
• Enlarged prostate (retention)
• Chronic lung condn
• Congestive cardiac condn
• Pyloric obstr, pylorospasm, cardiospasm
DR GEETANJALI VERMA

19. DR GEETANJALI VERMA