Methantheline is a synthetic quarternary ammonium antimuscarinic used to relieve cramps or spasms of the stomach, intestines, and bladder. It is indicated for the treatment of peptic ulcer disease, irritable bowel syndrome, pancreatitis, gastritis, biliary dyskinesia, pylorosplasm, and reflex neurogenic bladder in children. It can be used together with antacids or other medicines, such as H2-receptor antagonists, in the treatment of peptic ulcer. Methantheline bromide (diethyl-methyl [2-(9 xanthenyl carbonyloxy) ethyl] ammonium bromide) is marketed to treat neurogenic bladder instability. In comparison with atropine, it influences the parasympathetic nervous transmission more by ganglionic rather than peripheral muscarinic receptor blockade. Methantheline inhibits the muscarinic actions of acetylcholine on structures innervated by postganglionic cholinergic nerves as well as on smooth muscles that respond to acetylcholine but lack cholinergic innervation. Clinical effects after single therapeutic doses of 50-100 mg last for about 6 hours which is longer than after atropine. The drug relaxes smooth muscles of the gastrointestinal and urogenital tract. Furthermore, it inhibits bronchial, salivary and sweat glands secretion, lowers the production of gastric juice and disturbs accommodation. A recent randomised double-blind placebo-controlled study using a new commercial preparation of methantheline bromide (Vagantin, Germany) demonstrated significant sweat reduction and was evaluated as is an effective and safe treatment of axillary hyperhidrosis.

Diphemanil methylsulfate (Prantal), a quarternary amine, is a highly specific parasympathetic blocking agent.

Evans Blue (EBD) is an azo dye which has a very high affinity for serum albumin. It can be useful in physiology in estimating the proportion of body water contained in blood plasma. Evans Blue Dye is widely used to study blood vessel and cellular membrane permeability as it is non-toxic, it can be administered as an intravital dye and it binds to serum albumin – using this as its transporter molecule. The EBD–albumin conjugate (EBA) can be: (i) identified macroscopically by the striking blue colour within tissue; (ii) observed by red auto-fluorescence in tissue sections examined by fluorescence microscopy; and (iii) assessed and quantified by spectrophotometry for serum samples, or homogenised tissue. has recently been utilised in mdx mice to identify permeable skeletal myofibres that have become damaged as a result of muscular dystrophy. EBD has the potential to be a useful vital stain of myofibre permeability in other models of skeletal muscle injury and membrane-associated fragility. Evans Blue is a potent inhibitor of L-glutamate uptake into synaptic vesicles. It also inhibits AMPA and kainate receptor-mediated currents (IC50 values are 220 and 150 nM respectively). P2X-selective purinoceptor antagonist.

Dihydroergocornine is an ergot alkaloid, one of the three components of ergoloid (trade name Hydergine). Dihydroergocornine (as the component of Ergoloid mesylates) has been used to treat dementia and age-related cognitive impairment (such as in Alzheimer disease), as well as to aid in recovery after stroke. There is no specific evidence which clearly establishes the mechanism by which Hydergine® (ergoloid mesylates) preparations produce mental effects, nor is there conclusive evidence that the drug particularly affects cerebral arteriosclerosis or cerebrovascular insufficiency. Hydergine may stimulates dopaminergic and serotonergic receptors and blocks alpha-adrenoreceptors.

Dihydroergocristine is an ergot alkaloid that has an partial agonist activity on dopaminergic and alpha-adrenergic receptors and antagonist activity on serotonin receptors. The drug was approved by FDA in combination with other alkaloids (dihydroergocornine, dihydro-alpha-ergocryptine and dihydro-beta-ergocryptine mesylate salts) under the name Hydergine for the treatment of dimentia and cerebrovascular insufficiency.

Dihydro-alpha-ergocryptine is an ergot alkaloid that has an agonist activity on D2 dopaminergic receptors and a partial agonist activity on D1 receptors. It also demonstrated antagonistic activity towards alpha-adrenergic receptors. The drug was approved by FDA in combination with other alkaloids (dihydroergocornine, dihydroergocristine and dihydro-beta-ergocryptine mesylate salts) under the name Hydergine for the treatment of dimentia and cerebrovascular insufficiency.

Hexamethonium is a nicotinic cholinergic antagonist. It was used to treat hypertension, but has never been approved and was discontinued because of the non-specified treatment. When this drug tried to use in medical study via inhalation, one of the volunteer died, the death has been described as “particularly disturbing ”because it was a healthy volunteer who had no thing to gain by taking part in the study. This volunteer participated in a study designed to provoke a mild asthma attack in order to help doctors discover the reflex that protects the lungs of healthy people against asthma attacks. Hexamethonium is poorly absorbed from the gastrointestinal tract and does not cross the blood-brain barrier. Now it is widely used a research tool.

Thiphenamil, an antispasmodic drug with a local anesthetic activity, inhibits contraction. The clinical trials have shown that thiphenamil could suppress upper urinary tract contractility, and was suggested to use the drug for renal colic and stone management. In addition, this drug was studied for the treatment of detrusor incontinence in patients with detrusor instability. The results showed, that the drug caused a significant decrease in problems due to loss of urine when the patient was taking the drug compared to the placebo.

Caramiphen is a muscarinic M1 acetylcholine receptor antagonist, which was used for the treatment of Parkinson Disease and cough, but then there using were discontinued. Caramiphen is also used in local anesthesia, and effect could be achieved through the suppression of voltage-gated Na⁺ currents.