Details of Drug Interaction | MecDDI

Drug General Information (ID: DDIF2CYZE0)
Drug Name			Apomorphine		Drug Info		Guanfacine		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Dopaminergic Antiparkinsonism Agents				Antiadrenergic Agents
Structure

Mechanism of Apomorphine-Guanfacine Interaction (Severity Level: Moderate)
Additive hypotensive effects Click to Show/Hide Mechanism Graph

Drug Name		Apomorphine				Guanfacine
Mechanism 1		Antihypertensive agent				Antihypertensive agent Alpha-2 adrenergic receptor Agonist
Key Mechanism Factor 1
		Factor Name		Adrenergic receptor alpha-2				Structure Sequence
		Protein Family		G-protein coupled receptor 1 family
		Protein Function		Alpha-2 adrenergic receptors mediate the catecholamine-induced inhibition of adenylate cyclase through the action of G proteins. The rank order of potency for agonists of this receptor is oxymetazoline > clonidine > epinephrine > norepinephrine > phenylephrine > dopamine > p-synephrine > p-tyramine > serotonin = p-octopamine. For antagonists, the rank order is yohimbine > phentolamine = mianserine > chlorpromazine = spiperone = prazosin > propanolol > alprenolol = pindolol. Click to Show/Hide
Mechanism Description		Additive hypotensive effects by the combination of Apomorphine and Guanfacine
Mechanism 2		Hypotensive effects				Antihypertensive agent Alpha-2 adrenergic receptor Agonist
Key Mechanism Factor 2
		Factor Name		Adrenergic receptor alpha-2				Structure Sequence
		Protein Family		G-protein coupled receptor 1 family
		Protein Function		Alpha-2 adrenergic receptors mediate the catecholamine-induced inhibition of adenylate cyclase through the action of G proteins. The rank order of potency for agonists of this receptor is oxymetazoline > clonidine > epinephrine > norepinephrine > phenylephrine > dopamine > p-synephrine > p-tyramine > serotonin = p-octopamine. For antagonists, the rank order is yohimbine > phentolamine = mianserine > chlorpromazine = spiperone = prazosin > propanolol > alprenolol = pindolol. Click to Show/Hide
Mechanism Description		Additive hypotensive effects by the combination of Apomorphine and Guanfacine

Recommended Action
Management		Caution and close monitoring for altered efficacy and safety are recommended if patients receive apomorphine with an antihypertensive agent or vasodilator. Patients should be made aware of the possible side effects (e.g., dizziness, lightheadedness, orthostasis) and be cautioned about driving, operating machinery, or performing other hazardous tasks. They should also be advised to avoid rising abruptly from a sitting or recumbent position and to contact their physician if they experience symptoms of hypotension such as dizziness, lightheadedness, or fainting.

References
1	Bailey DG, Dresser GK "Natural products and adverse drug interactions." Can Med Assoc J 170 (2004): 1531-2. [PMID: 15136542]
2	Ho PC, Ghose K, Saville D, Wanwimolruk S "Effect of grapefruit juice on pharmacokinetics and pharmacodynamics of verapamil enantiomers in healthy volunteers." Eur J Clin Pharmacol 56 (2000): 693-8. [PMID: 11214778]
3	Product Information. Apokyn (apomorphine). Mylan Pharmaceuticals Inc, Morgantown, WV.