<prompt> Which of the following drug is alpha 2 agonist?ApraclonidineTimololPG analoguesPG analogues  <response>: Apraclonidine - Selective alpha 2 agonist. Useful in glaucoma. Alpha agonists Brimonidine and apraclonidine are contraindicated in hypeensive crisis. Dipivefrin is a prodrug which is conveed into epinephrine inside ttre eyeUall, so can safely be used in hypeension. REF : katzung pharmacology : 14th ed 