Cyclopentamine is a sympathomimetic alkylamine, classified as a vasoconstrictor. Cyclopentamine was indicated in the past as an over-the-counter medication for use as a nasal decongestant, notably in Europe and Australia, but has now been largely discontinued possibly due to the availability, effectiveness, and safety of a structurally similar drug, propylhexedrine used for relief of congestion due to colds, common cold, hay fever, or other allergies. Cyclopentamine acts as a releasing agent of the catecholamine neurotransmitters norepinephrine (noradrenaline), epinephrine (adrenaline), and dopamine. Cyclopentamine effects on norepinephrine and epinephrine mediate its decongestant effects, while its effects on all three neurotransmitters are responsible for its stimulant properties. Cyclopentamine was acting as nonspecific spasmolytic, similar to papaverine, in the rabbit ileum. It was demonstrated that cyclopentamine was a very weak alpha-adrenergic receptor stimulant and a weak beta-adrenergic receptor blocker. Cyclopentamine also potentiated the auto-inhibition produced by high doses of isoproterenol and the effect lasted as long as the autoinhibition persisted. It was suggested that the blockade by both drugs was the result of a direct action on the beta receptors. When ingested orally in sufficient quantities, cyclopentamine produces similar effects to amphetamine, methamphetamine, and propylhexedrine.

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.

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.

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

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.

Dimethisoquin (also known as Quinisocaine and QUOTANE) is a topical anesthetic used as an antipruritic. It was shown that dimethisoquin inhibits nicotinic acetylcholine receptors (alpha4/beta4 and alpha4/beta2) with the maximum inhibition potency occurring for the α4β4 subtype.

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.

Metabutethamine hydrochloride was used as a local anesthetic.