Procyclidine is a muscarinic antagonist that crosses the blood-brain. Procyclidine hydrochloride (brand name Kemadrin) is a synthetic antispasmodic compound of relatively low toxicity. It has been shown to be useful for the symptomatic treatment of parkinsonism (paralysis agitans) and extrapyramidal dysfunction caused by tranquilizer therapy. Procyclidine hydrochloride was developed at The Wellcome Research Laboratories as the most promising of a series of antiparkinsonism compounds produced by chemical modification of antihistamines. Kemadrin is indicated in the treatment of parkinsonism including the postencephalitic, arteriosclerotic, and idiopathic types. Partial control of the parkinsonism symptoms is the usual therapeutic accomplishment. Procyclidine hydrochloride is usually more efficacious in the relief of rigidity than tremor; but tremor, fatigue, weakness, and sluggishness are frequently beneficially influenced. It can be substituted for all the previous medications in mild and moderate cases. For the control of more severe cases, other drugs may be added to procyclidine therapy as indications warrant. The mechanism of action is unknown. It is thought that procyclidine acts by blocking central cholinergic receptors, and thus balancing cholinergic and dopaminergic activity in the basal ganglia. Pharmacologic tests have shown that procyclidine hydrochloride has an atropine-like action and exerts an antispasmodic effect on smooth muscle. It is a potent mydriatic and inhibits salivation. It has no sympathetic ganglionblocking activity in doses as high as 4 mg/kg, as measured by the lack of inhibition of the response of the nictitating membrane to preganglionic electrical stimulation.

Propyliodone (INN, trade name Dionosil) is a molecule used as a contrast medium. It was developed by a team at Imperial Chemical Industries in the late 1930s. Propyliodone used as radiopque medium for brochographic use. When directly instilled into the bronchi resulting in well-defined bronchograms for atleast 30 min. Because of its toxicity, Propyliodone should only be used if absolutely essential. It is of Synthetic origin and belongs to Iodinated Radio-opaque Compounds. It belongs to Radiopaque Agents pharmacological group on the basis of mechanism of action and also classified in Diagnostic Aids pharmacological group. Oral absorption of Propyliodone is found to be 101% and metabolism is reported Lungs and Gut wall. Propyliodone is primarily indicated in conditions like Paget's disease of bone, Radiological contrast agent. Propyliodone produces potentially life-threatening effects which include Fever, Anaphylaxis, Repiratory obstruction, Cerebral embolization, which are responsible for the discontinuation of Propyliodone therapy. The signs and symptoms that are produced after the acute overdosage of Propyliodone include Airway obstruction. The symptomatic adverse reactions produced by Propyliodone are more or less tolerable and if they become severe, they can be treated symptomatically, these include Headache, Fever, Malaise, Nausea and vomiting, Aching joints.

HEPTABARBITAL is an intermediate or short term barbiturate. It binds to the GABAA receptor at either the alpha or the beta subunit. This GABAA receptor binding decreases input resistance, depresses burst and tonic firing, especially in ventrobasal and intralaminar neurons, while at the same time increasing burst duration and mean conductance at individual chloride channels; this increases both the amplitude and decay time of inhibitory postsynaptic currents. HEPTABARBITAL was formerly used as a sedative and hypnotic drug.

Reserpine is an alkaloid, isolated from the Rauwolfia serpentina plant and developed by Ciba pharma. Reserpine was approved by FDA for the treatment of hypertension and psychotic disorders. The drug exerts its effect by blocking two vesicular monoamine transporters, VMAT1 and VMAT2. The blockade results in vesicles that lose their ability to store neurotransmitter molecules. Neurotransmitters, thus retained in cytosol, are then neutralized by MAO.

Digoxin is a cardiac glycoside derived from the purple foxglove flower. In 1785, the English chemist, botanist, and physician Sir William Withering published his findings that Digitalis purpurea could be used to treat cardiac dropsy (congestive heart failure; CHF). Digoxin has been in use for many years, but was not approved by the FDA for treatment of heart failure (HF) until the late 1990s. Another FDA indication for digoxin is atrial fibrillation (AF). Digoxin also has numerous off-label uses, such as in fetal tachycardia, supra-ventricular tachycardia, cor pulmonale, and pulmonary hypertension. Digitoxin inhibits the Na-K-ATPase membrane pump, resulting in an increase in intracellular sodium and calcium concentrations. Increased intracellular concentrations of calcium may promote activation of contractile proteins (e.g., actin, myosin). Digoxin also has Para sympathomimetic properties. By increasing vagal tone in the sinoatrial and atrioventricular (AV) nodes, it slows the heart rate and AV nodal conduction.

PENTHIENATE, a synthetic anticholinergic, depresses the motility and secretion of the stomach and reduces the motor activity of the intestine by blocking vagal stimulation. It is used in the treatment of peptic ulcer and dyspepsia.

Piperidolate hydrochloride is an antimuscarinic, inhibits intestinal cramp induced by acetylcholine (rats and dogs. It’s usually used to kill the cramp-like pain of gastric/duodenal ulcer, gastritis, enteritis, gallstones, cholecystitis and biliary tract dyskinesia and to improve some symptoms in threatened miscarriage/premature delivery. Piperidolate blocked the contraction of ACh, Ba ++ and electrical stimulations on the isolated rat, mouse and guinea-pig ileum and trachea. In guinea-pig teania caeci, piperidolate like papaverine blocked specifically the tonic response, however, piperidolate in high doses completely blocked both spike and tonic responses. These results indicate that spasmolytic action of piperidolate like that of papaverine may depend upon inhibition of the release of store Ca++. Moreover piperidolate, given at high doses, may inhibit the contractile elements in the smooth muscle. In the rat uterus pretreated with sex hormones, piperidolate nonspecifically blocked the contraction of ACh, Ba ++ and oxytocin and sex hormones had no influence on the spasmolytic action of piperidolate.

Thiamylal is a barbiturate that is administered intravenously for the production of complete anesthesia of short duration, for the induction of general anesthesia, or for inducing a hypnotic state. Thiamylal, a barbiturate, is used in combination with acetaminophen or aspirin and caffeine for its sedative and relaxant effects in the treatment of tension headaches, migraines, and pain. Barbiturates act as nonselective depressants of the central nervous system (CNS), capable of producing all levels of CNS mood alteration from excitation to mild sedation, hypnosis, and deep coma. In sufficiently high therapeutic doses, barbiturates induce anesthesia. Thiamylal binds at a distinct binding site associated with a Cl- ionopore at the GABAA receptor, increasing the duration of time for which the Cl- ionopore is open. The post-synaptic inhibitory effect of GABA in the thalamus is, therefore, prolonged.

AZAPETINE, a benzazepine derivative, is an alpha-1 adrenoceptor antagonist. It is a potent arterial vasodilator in the treatment of peripheral vascular diseases.

Tridihexethyl is a synthetic anticholinergic agent which was marketed under the brand name Pathilon as an adjunct in the treatment of peptic ulcer disease. However, it is no longer available in the US market. Tridihexethyl may block all three types of muscarinic receptors including M-1 receptors in the CNS and ganglia, M-2 receptors in the heart, and M-3 receptors. The muscarinic acetylcholine receptors mediate various cellular responses including inhibition of adenylate cyclase, the breakdown of phosphoinositides, and modulation of potassium channels through the action of G proteins. Tridihexethyl inhibits vagally mediated reflexes by antagonizing the action of acetylcholine. This, in turn, reduces the secretion of gastric acids in the stomach. Tridihexethyl was also examined for effect on patients with acquired nystagmus where four out of six patients showed improvement, but due to the profile usage of Tridihexethyl to treat nystagmus was limited.