Scopolamine is naturally plant obtained alkaloid drug, obtained from family of Solanaceae, such as nightshade, jimsonweed and henbane. It is also called hyoscine. Scopolamine is very effective natural drug to treat the motion sickness, nausea and vomiting due to its ability to dispirit the central nervous system (brain and spinal cord). It has depressant act on parasympathetic nerve and in larger doses on autonomic ganglia. Scopolamine is also used to arid up secretions and widen the bronchi during anesthesia and to expand the pupil throughout opthalmological procedures. The drug is pharmacologically very active of several alkaloid substances found in belladonna, due to its superior solubility, that permits more speedy passageway to the site of action.
- Molecular formula: C17H21NO4
- Molar mass: 303.35 g/mol
- Metabolism: Liver
- Elimination half life: 4.5 hours
- Other name :Hyoscine Hydrobromide , scopolamine hydrobromide
BIOSYNTHESIS AND COMPOSTION
The biosynthesis of hyoscine starts with the decarboxylation of L-ornithine to putrescine by ornithine decarboxylase. Putrescine is methylated to N-methylputrescine by putrescine N-methyltransferase.
A putrescine oxidase that explicitly perceives methylated putrescine catalyzes the deamination of this compound to 4-methylaminobutanal, which at that point goes through an unconstrained ring development to N-methyl-pyrrolium cation. In the subsequent stage, the pyrrolium cation gathers with acetoacetic corrosive yielding hygrine. No enzymatic movement could be shown to catalyze this response. Hygrine further modifies to tropinone.
In this way, tropinone reductase I changes over tropinone to tropine, which gathers with phenylalanine-inferred phenyllactate to littorine. A cytochrome P450 named Cyp80F1 oxidizes and revamps littorine to hyoscyamine aldehyde. In the last advance, hyoscyamine goes through epoxidation catalyzed by 6beta-hydroxyhyoscyamine epoxidase yielding hyoscine.
BRIEF DESCRIPTION AND NATURAL SOURCE
Scopolamine is from the secondary metabolites obtained from plants, nightshade, henbane, jimson weed, corkwood and trumpets. These plants produce toxic compound, belladonna alkaloids, as a protective agent. It has a lot of benefits and the major highlight is prevention of motion sickness. Scopolamine stops the way of communication between the nerves of the vestibule and the vomiting centre. It is found to be more effective when taken before the onset of motion sickness. Basically it prevents the nausea and vomiting caused by motion sickness or anesthesia given during a surgery. Moreover scopolamine has many other benefits including stomach or intestinal problems, Parkinson condition and muscle spasm.
Scopolamine is also an effective inhibitor of gastrointestinal activities and relaxes the gastrointestinal tract. It has a superior central depressant effect than atropine, and its antiemetic action is accredited to an obstruction of muscarinic cholinergic receptors in the area postrema or allied nuclei of the dorsal vagal complex.
Scopolamine is available worldwide in different formulations including oral, parenteral, and transdermal.
USES IN PHARMACOLOGICAL APPLICATIONS
Scopolamine is an anticholenergic when applied in the form of a patch; drug patch scopolamine is widely used for prevention of motion sickness. The patch is placed behind the ear at dry, clean and hairless area where scopolamine patch can stickled up to 3 days. And the patch is applied 3 to 4 hours before contact to motion and must be worn as for as stimulus is there.
It can be further used to treat conditions like
■ Excessive sweating
■ Asthma attacks
■ Chemotherapy nausea
■ Smoking cessation therapy
■ Gastrointestinal spasm
■ Reducing gland secretion
Hence scopolamine has many therapeutic properties
SIDE EFFECTS AND PRECAUTIONS
Scopolamine may temporarily cause blur vision and widened pupils when it comes to contact with eyes.
Some other side effects involves acute angle closure glaucoma, toxic psychosis(uncertainty, perplexity, confabulation), drowsiness and impaired short term memory.
It should not be used for a long time because the side effects become severe.
Prolonged use may lead to increased gastrointestinal motility and hyper salivation.
Scopolamine should be used with caution for patients of myasthenia gravis, this condition is caused by the lack of proper nerve impulse transmission due to antibodies to acetylcholine receptors, which results muscle fatigue.
Patients should not use scopolamine patch if they have scheduled MRI. The layer of patch contains metal so it can burn the skin.
Proper hand washing to be carried out after touching the patch.
Pregnant women and breastfeeding mothers should use scopolamine with the advice of Doctor.
Some other mild side effects are Constipation, dry mouth, headache, dizziness and fever.