Hyoscyamine

Hyoscyamine

Clinical data
Trade names	Anaspaz, Levbid, Levsin
AHFS/Drugs.com	Monograph
MedlinePlus	a684010
Pregnancy category	C
Routes of administration	Oral, Injection
ATC code	A03BA03 (WHO)
Legal status
Legal status	AU: S4 (Prescription only) US: ℞-only
Pharmacokinetic data
Bioavailability	50% Protein binding
Metabolism	Hepatic
Biological half-life	3–5 hrs.
Excretion	Urine
Identifiers
IUPAC name (S)-(1R,3r,5S)-8-methyl-8-azabicyclo[3.2.1]octan-3-yl 3-hydroxy-2-phenylpropanoate
CAS Number	101-31-5 Y
PubChem CID	154417
DrugBank	DB00424 Y
ChemSpider	10246417 Y
UNII	PX44XO846X
ChEBI	CHEBI:17486 Y
ChEMBL	CHEMBL1697729 N
ECHA InfoCard	100.002.667
Chemical and physical data
Formula	C17H23NO3
Molar mass	289.375 g/mol
3D model (Jmol)	Interactive image
SMILES CN3[C@H]1CC[C@@H]3C[C@@H](C1)OC(=O)[C@H](CO)c2ccccc2
InChI InChI=1S/C17H23NO3/c1-18-13-7-8-14(18)10-15(9-13)21-17(20)16(11-19)12-5-3-2-4-6-12/h2-6,13-16,19H,7-11H2,1H3/t13-,14+,15+,16-/m1/s1 Y Key:RKUNBYITZUJHSG-FXUDXRNXSA-N Y
NY (what is this?)

Hyoscyamine (also known as daturine) is a tropane alkaloid. It is a secondary metabolite found in certain plants of the family Solanaceae, including henbane (Hyoscyamus niger), mandrake (Mandragora officinarum), jimsonweed (Datura stramonium), tomato (Solanum lycopersicum) and deadly nightshade (Atropa belladonna). It is the levorotary isomer of atropine (third of the three major nightshade alkaloids) and thus sometimes known as levo-atropine. Hyoscyamine should not be confused with hyoscine, an older alternate name for the related nightshade-derived anticholinergic scopolamine for which it is the precursor.

Brand names for hyoscyamine include Symax, HyoMax, Anaspaz, Egazil, Buwecon, Cystospaz, Levsin, Levbid, Levsinex, Donnamar, NuLev, Spacol T/S and Neoquess.

Hyoscyamine is an antagonist of muscarinic acetylcholine receptors (antimuscarinic). It blocks the action of acetylcholine at parasympathetic sites in sweat glands, salivary glands, stomach secretions, heart muscle, sinoatrial node, smooth muscle in the gastrointestinal tract, and the central nervous system. It increases cardiac output and heart rate, lowers blood pressure and dries secretions. It may antagonize serotonin. At comparable doses, hyoscyamine has 98 per cent of the anticholinergic power of atropine. The other major belladonna-derived drug scopolamine has 92 per cent of the antimuscarinic potency of atropine.