Drug General Information (ID: DDI32T4IHV)
Drug Name			Flavoxate		Drug Info		Levodopa		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Parasympatholytics				Dopaminergic Antiparkinsonism Agents
Structure

Mechanism of Flavoxate-Levodopa Interaction (Severity Level: Moderate)
Altered gastrointestinal dynamics Click to Show/Hide Mechanism Graph
Drug Name		Flavoxate				Levodopa
Mechanism		Decrease gastrointestinal motility				Absorption is influenced by gastrointestinal motility
Key Mechanism Factor 1
		Factor Name		Gastrointestinal Motility
		Factor Description		Gastrointestinal motility is an important factor in determining the absorption of orally administered drugs, and it controls the residence time of the drug in the digestive tract.
Mechanism Description		Altered absorption of Levodopa due to GI dynamics variation caused by Flavoxate

Recommended Action
Management		Although certain anticholinergic agents may be used as adjunctive therapy in Parkinson's disease, clinicians should recognize their potential to reduce the oral bioavailability of levodopa in some patients. Pharmacologic response to levodopa should be monitored more closely whenever anticholinergic agents are added to or withdrawn from therapy, and the dosages of the drugs adjusted as necessary.

References
1	Algeri S, Cerletti C, Curcio M, et al. "Effect of anticholinergic drugs on gastro-intestinal absorption of L-dopa in rats and man." Eur J Pharmacol 35 (1976): 293-9. [PMID: 1248506]
2	Bergmann S, Curzon G, Friedel J, et al "The absorption and metabolism of a standard oral dose of levodopa in patients with parkinsonism." Br J Clin Pharmacol 1 (1974): 417-24. [PMID: 22454921]
3	Birket-Smith E "Abnormal involuntary movements induced by anticholinergic therapy." Acta Neurol Scand 50 (1974): 801-11. [PMID: 4155220]
4	Fermaglich J, O'Dougherty DS "Effect of gastric motility on levodopa." Dis Nerv Syst 33 (1972): 624-5. [PMID: 4649158]
5	Hughes R, Polgar JG, Weightman D, Walton JN "Levodopa in Parkinsonism: the effects of withdrawal of anticholinergic drugs." Br Med J 2 (1971): 487-91. [PMID: 5579489]
6	Rivera-Calimlim L, Dujovne CA, Morgan JP, Lasagna L, Bianchine JR "Absorption and metabolism of L-dopa by the human stomach." Eur J Clin Invest 1 (1971): 313-20. [PMID: 5558777]