However, transdermal selegiline, known by its trade name Emsam, is still contraindicated. Transdermal selegiline results in higher plasma levels at which it behaves like a non-selective MAO inhibitor. Concominant use of entacapone, a component of carbidopa/levodopa/entacapone, with MAO inhibitors may increase toxicity of MAO inhibitors. Levodopa, also a component of carbidopa/levodopa/entacapone, in combination with MAO inhibitors may result in hypertensive reactions. Mechanism of action
Levodopa is the immediate precursor to dopamine. Entacapone is a selective, reversible catechol-O-methyltransferase (COMT) inhibitor that prevents the degradation of levodopa. Entacapone does not cross the blood–brain barrier. Carbidopa is a peripheral aromatic L-amino acid decarboxylase (AADC) inhibitor. Carbidopa, which also does not cross the blood–brain barrier, is combined with levodopa to prevent its conversion to dopamine in the periphery. Society and culture
Extension
As of 2010, applications for extending the indication of carbidopa/levodopa/entacapone to people requiring initiation of levodopa therapy have been under review by the European Medicines Agency (EMA) and the U.S. Food and Drug Administration (FDA), based on the favorable results from FIRST-STEP, a study conducted in North America and Europe by Novartis from 2005, to 2007 (see below). References
External links
"Carbidopa mixture with entacapone and levodopa". Drug Information Portal. U.S. National Library of Medicine. "Entacapone/Carbidopa/Levodopa (marketed as Stalevo) Information". U.S. Food and Drug Administration (FDA). 6 April 2017.
Portia may refer to:

Biology
Portia (spider), a genus of jumping spiders
Anaea troglodyta or Portia, a brush-footed butterfly
Portia tree, a plant native to Polynesia
Ctt. Portia, an orchid Cattlianthe

Medication
A form of birth control made of ethinylestradiol/levonorgestrel

Other uses
Portia (moon), a moon of Uranus
Portia Club, a womens club in Payette, Idaho/USA
Portia, Missouri, a community in the United States
PORTIA portfolio-management software from Thomson Financial
HMS Lennox (1914) or HMS Portia, a Laforey-class destroyer launched in 1914

People with the given name
Portia Arthur (born 1990), Ghanaian author, writer and reporter
Porcia Catonis, the wife of Roman senator Marcus Junius Brutus (fictionalized as  a character in William Shakespeares play Julius Caesar as "Portia")
Portia Dawson, American actress
Portia de Rossi or Portia DeGeneres, Australian-born actress
Portia Doubleday, American actress
Portia Geach (1873–1959), Australian artist and feminist
Portia Holman (1903–1983), Australian child psychiatrist
Portia Mansfield (1887–1979), American dance educator and choreographer
Portia Simpson-Miller, political leader of Jamaicas Peoples National Party and Prime Minister of Jamaica
Portia White, Canadian singer
Portia Zvavahera (born 1985), Zimbabwean painter
Portia, pen name of Abigail Adams (1744-1818)
Portia, pen name of Grizelda Elizabeth Cottnam Tonge (1803-1825)

Fictional
Portia (The Merchant of Venice), a character in William Shakespeares play The Merchant of Venice
Portia Quayne, the protagonist in The Death of the Heart by Elizabeth Bowen
Portia Gibbons, character on The Mighty B!