Test 190  (Ocular pharmacology)
1. The following are true about ophthalmic drugs:
a. non-ionized drugs are more lipid soluble and 
    therefore penetrate the eye better

b. ionized drugs are more stable in tear and penetrate
    the stroma better

c. most ocular drugs are weak acid

d. making the pH of an ophthalmic drug more basic 
    will increase ocular penetration 

e. contact time with the cornea is increased by increasing
    the viscosity of the drugs


2. Malignant hyperthermia:

a. is an autosomal recessive disorder

b. occurs with exposure to inhalation anaesthesia 

c. causes hypokalaemia

d. causes elevated serum creatinine kinase

e. should be treated with intravenous dantrolene


3. Adrenaline:
a. stimulates the a receptor more than b receptors

b. decreases trabecular outflow

c. increases aqueous production

d. can be used to prolong the action of local anaesthetic

e. can be added to the irrigation fluid during cataract 
    surgery to maintain pupil dilatation

. 4. Apraclonidine:
a. is an agonist of both a1 and a2 receptors

b. increases trabecular outflow

c. loses its effect on intraocular pressure control over time

d. crosses the blood brain barrier readily

e. causes eyelid retraction in patients with Horner's 

5. 5-fluorouracil:

a. is derived from Streptococcus caespitosis

b. is a purine analog

c. inhibit thymidylate synthetase

d. does not inhibit proliferating cells which are not 
    synthesizing DNA

e. inhibits fibroblast proliferation

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