Smooth muscle relaxants antispasmodics

Actions Antioxidant, anti diuretic, smooth muscle relaxant, antispasmodic, immunostimulant (stimulates interferon production, enhances antibody formation, stimulates phagocytosis, antistressor, adrenal tonic, thymus stimulant), antiulcer, anti-inflammatory, tumor inhibitor, free radical inhibitor, antihepatoxic, antimalarial, protects from effects of radiation exposure, gentle laxative, expectorant, demulcent, immunomodulator, antihyperglycemic, reduces gastric secretions, stimulates pancreatic secretions. 

Nonselective antimuscarinic drugs have been employed in the therapy of peptic ulcers (see Chapter 40) because they can reduce gastric acid secretion they also have been used as adjunctive therapy in the treatment of irritable bowel syndrome. Antimuscarinic drugs can decrease the pain associated with postprandial spasm of intestinal smooth muscle by blocking contractile responses to ACh. Some of the agents used for this disorder have only antimuscarinic activity (e.g., propantheline), while other drugs have additional properties that contribute to their antispasmodic action. Dicyclomine (Bentyl) and oxybutynin (Ditropan) at therapeutic concentrations primarily have a direct smooth muscle relaxant effect with little antimuscarinic action. 

It has got antispasmodic with direct smooth muscle relaxant action. It is used in morning and motion sickness. 

Antispasmodics (see below) are given for abdominal pain, although there is little objective evidence for their efficacy from controlled clinical trials. The generation of evidence is complicated by the variable nature of IBS symptoms, the patients who suffer from them, and the high rate of placebo response in this condition. There are two main classes of antispasmodic, the antimuscarinic drugs and drugs which are direct smooth muscle relaxants. 

SMOOTH MUSCLE RELAXANT and ANTISPASMODIC with SOme LOCAL ANAESTHETIC activity. 

ANTAGONIST and SMOOTH MUSCLE RELAXANT activity. It was formerly used as an antispasmodic in the treatment of irritable bowel syndrome. 

The four benzylisoquinolines of clinical interest are papaverine, used as an antispasmodic and peripheral vasodilator dioxyline, also a peripheral and coronary vasodilator the closely related ethaverine, which is another smooth muscle relaxant and trimetoquinol, which is a bronchodilator. Several new analogs of these compounds have been screened for pharmacological activity. ... 

Other recently reported activities of St. John s wort include in vitro and in vivo antispasmodic, smooth muscle relaxing, and bronchodilating effects (rabbit jejunum, guinea pig tracheal preparations, rat bladder, and whole mice) anticonvulsant effects in epileptic mice as well as inhibition of prolactin secretion in mice (100 mg/kg, 15 days). ... 

Colofac is the proprietary preparation of mebeverine, which is an antispasmodic useful in irritable bowel syndrome. Mebeverine is a direct relaxant of the smooth muscle and, unlike hyoscine, is not an antimuscarinic. 

Mebeverine is an antispasmodic that reduces gastric and intestinal motility by direct relaxation of the intestinal smooth muscle. It can be used to relieve pain in irritable bowel syndrome and diverticular disease. Like all antispasmodics, mebeverine is contraindicated in paralytic ileus. 

Mecfianism of Action A GI antispasmodic and anticholinergic agent that directly acts as a relaxant on smooth muscle. Therapeutic Effect Reduces tone and motility of GI tract. 

Methylchromone (Tricromyl or Crodimyl) possesses muscle relaxant properties and exerts a vasodilator effect on coronary blood vessels, whilst the flavone derivative Flavoxate (Urispas) (725) is an antispasmodic agent which reduces smooth muscle spasm in the urinary tract. The isofiavone Formononetin (726) is a diuretic and Dimeffine (Remeflin) (727) is a respiratory stimulant. 

The aromatic oil extracted from thyme leaves contains thymol and carvacol, which have preservative, antibacterial, and antifungal properties. Thyme is a bronchial antispasmodic that relaxes muscles in the respiratory tract, an effect that makes it a good treatment for bronchitis and whooping cough. Thyme also relaxes smooth muscles in the gastrointestinal tract and the uterus, making it effective as a digestive aid and reliever of menstrual cramps. 

Tertiary amines used for their antispasmodic properties are dicyclomine hydrochloride (Ben-tyl, others), oxyphencyclimine hydrochloride (daricon), flavoxate hydrochloride (Uripas), and oxyburynin chloride (Ditropan). The latter two are indicated specifically for urological disorders. These agents appear to exert some nonspecific direct relaxant effect on smooth muscle. In therapeutic doses they decrease spasm of the gastrointestinal tract, biliary tract, ureter, and uterus characteristic atropine-like effects on the salivary glands and the eye also are seen with oxybutynin. 

Documented effects In experiment on animals, this plant species had hypotensive, antispasmodic, anti-inflammatory, and styptic properties (Plant Resources of the USSR 1985). A methanol extract of the plant induced a dose-dependent relaxation of duodenal smooth muscle in rabbits (Atta and Mouneir 2004). Mice fed high doses of the plant died or had severe hepatic necrosis and gastritis after 4-7 days. Mice fed low doses of the plant had no clinical disease or large lesions, but developed mild multifocal hepatitis and gastritis (Schultheiss et al. 1995). 

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