mydriatics & cycloplegics class / power point presentation for O.A student 2nd year of SCEH, LAHAN,NEPAL

1. Mydriatics & Cycloplegics :
Defination, Mechanism of action,
indications,contraindications, side
effects
SCEH, Lahan.

2. Defination
• Mydriatics are the group of drugs that are used for dilatation of
pupil. :: detail fundus examination.
• Cycloplegics are drugs that are used for dilatation as well as
for paralysing sphincter muscle. Detailed fundus examination,
cycloplegic refraction.

3. Classification
• Natural alkaloids :Atropine, Hyoscine (Scopolamine).
• Semi synthetic : Homatropine.
• Synthetic :
a) Mydriatics : Cyclopentolate, Tropicamide.
b) Antisecretory- antispasmodics : Dicyclomine
c) Antiparkinsonism : Dicyclomine

4. ATROPINE
• Mechanism of action : block actions of Acetylcholine on
autonomic effectors & in the CNS via muscarinic receptor.
• Topical instillation causes
1. Mydriasis
2. Abolition of light reflex
3. Cycloplegics (lasts for 7-10 days).
4. Mild anaesthetic action on the cornea.

5. ATROPINE
• Has effect in other parts of our body : CNS, CVS, GI, Smooth
muscle, glands.

6. ATROPINE : Indications
• Mydriasis, detailed fundus examination and cycloplegic
refraction.
• Inflammatory condition : Uveitis, corneal ulcer,
endophthalmitis. Breaks synechiae , relieves ciliary spasm
• Used in glaucoma but only in neovascular & malignant
glaucoma.

7. ATROPINE : Side effects
• Photophobia.
• Blurring of vision.

8. ATROPINE : Contraindication
• Acute congestive Glaucoma .

9. Mydriatics
• Tropicamide : potent and quickest of all mydriatics drugs (lasts
for 6 hours).
• Tropicamide with phenylephrine : faster and more potent.
• Cyclopentolate : potent drug and works for 2-3 days after
instillation.

10. Indications
• Mydriasis, detailed fundus examination and cycloplegic
refraction.
• Inflammatory condition : Uveitis, corneal ulcer,
endophthalmitis. Breaks synechiae , relieves ciliary spasm
• Used in glaucoma but only in neovascular & malignant
glaucoma.

11. Side effects
• Photophobia.
• Blurring of vision.

12. Contraindication
• Acute congestive Glaucoma

13. Thank you