Details of Drug Interaction | MecDDI

Drug General Information (ID: DDIU3Q7HPK)
Drug Name			Terazosin		Drug Info		Levodopa		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Antineoplastics				Dopaminergic Antiparkinsonism Agents
Structure

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

Drug Name		Terazosin				Levodopa
Mechanism 1		Antihypertensive agent Alpha-1 adrenergic receptor Antagonist				Antihypertensive agent
Key Mechanism Factor 1
		Factor Name		Adrenergic receptor alpha-1				Structure Sequence
		Protein Family		G-protein coupled receptor 1 family
		Protein Function		This alpha-adrenergic receptor mediates its action by association with G proteins that activate a phosphatidylinositol-calcium second messenger system. Its effect is mediated by G(q) and G(11) proteins. Nuclear ADRA1A-ADRA1B heterooligomers regulate phenylephrine(PE)-stimulated ERK signaling in cardiac myocytes. Click to Show/Hide
Mechanism Description		Additive hypotensive effects by the combination of Terazosin and Levodopa
Mechanism 2		Antihypertensive agent Alpha-1 adrenergic receptor Antagonist				Hypotensive effects
Key Mechanism Factor 2
		Factor Name		Adrenergic receptor alpha-1				Structure Sequence
		Protein Family		G-protein coupled receptor 1 family
		Protein Function		This alpha-adrenergic receptor mediates its action by association with G proteins that activate a phosphatidylinositol-calcium second messenger system. Its effect is mediated by G(q) and G(11) proteins. Nuclear ADRA1A-ADRA1B heterooligomers regulate phenylephrine(PE)-stimulated ERK signaling in cardiac myocytes. Click to Show/Hide
Mechanism Description		Additive hypotensive effects by the combination of Terazosin and Levodopa

Recommended Action
Management		Hemodynamic responses should be monitored during coadministration, especially during the first few weeks of therapy. Dose adjustments of the antihypertensive agent may be required. Patients should be advised to notify their physician if they experience dizziness or syncope.

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. Stalevo 150 (carbidopa/entacapone/levodopa). Novartis Pharmaceuticals, East Hanover, NJ.