Isoetharine is a beta-2 adrenergic receptor agonist, which was developed by Max Bockmuhl, Gustav Erhart and Leonhard Stein at the Hochst laboratories of I.G. Farbenindustrie in 1934. By binding to beta-2 adrenergic receptors on bronchial cell membranes, isoetharine increases the level of cAMP and thus stimulates the relaxation of smooth-muscle cells, stabilizes mast cells and inhibits histamine release. Isoetharine was approved by FDA for the symptomatic relief of bronchiospasms in patients with chronic bronchitis or emphysema (aerosol and solution for inhalation), however, later on the drug was discontinued.

Isoetharine is a beta-2 adrenergic receptor agonist, which was developed by Max Bockmuhl, Gustav Erhart and Leonhard Stein at the Hochst laboratories of I.G. Farbenindustrie in 1934. By binding to beta-2 adrenergic receptors on bronchial cell membranes, isoetharine increases the level of cAMP and thus stimulates the relaxation of smooth-muscle cells, stabilizes mast cells and inhibits histamine release. Isoetharine was approved by FDA for the symptomatic relief of bronchiospasms in patients with chronic bronchitis or emphysema (aerosol and solution for inhalation), however, later on the drug was discontinued.

PHENYRAMIDOL (ANALEXIN®), also known as fenyramidol, is an aminopyridine derivative, used as analgesic and muscle relaxant. It is considered as a drug that possibly causes hepatotoxicity.

Protokylol, a sympathomimetic drug has been utilized in general clinical practice as a bronchodilator. Protokylol (brand names Caytine, Ventaire) is a β-adrenergic receptor agonist which was used as a bronchodilator in Europe and the United States.

Isoxsuprine (used as isoxsuprine hydrochloride) is a drug used as a vasodilator in humans (under the trade name Duvadilan) and equines. Isoxsuprine is a β2 adrenoreceptor agonist that causes direct relaxation of uterine and vascular smooth muscle via β2 receptors. Isoxsuprine it is used in humans for treatment of premature labor, i.e. a tocolytic, and as a vasodilator for the treatment of cerebral vascular insufficiency, Raynaud's phenomenon, and other conditions. Isoxsuprine may increase the heart rate, cause changes in blood pressure, and irritate the GI tract. It should, therefore, be used with caution if combined with other drugs that affect blood pressure, such as sedatives and anesthetic drugs. Isoxsuprine is most commonly used to treat hoof-related problems in the horse, most commonly for laminitis and navicular disease, as its effects as a vasodilator are thought to increase circulation within the hoof to help counteract the problems associated with these conditions.

Pipradrol (Meratran) is a psychoactive agent and a central nervous system stimulant useful in the field of psychiatry. In vitro study has shown that pipradrol inhibits the reuptake of and stimulates the release of dopamine and norepinephrine. In these pharmacodynamic actions it is less potent than d-amphetamine. It was shown that pipradrol conditioned place preference (CPP) was blocked by selective D1 dopamine antagonist SCH23390 suggesting that a rewarding effect of pipradrol establishment of a CPP may involve activation of D1 dopamine receptors. Pipradrol was initially used as an adjunct in the dietary management of obesity as well as for the treatment of dementia. There have been a number of reports on the properties of pipradrol showing its favorable effects in the treatment of depression and fatigue status as well as a variety of other conditions including narcolepsy, spasmodic torticollis, schizophrenia and in geriatric practice. Pipradrol has a definite cerebral stimulating effect without affecting the blood pressure or respiration and has been used to counteract post-anasthetic and chlorpromazine depression in man. Structurally related to -phenylmethylamphetamine, a potent stimulant with a long half-life, pipradrol differs from amphetamine in that its action is more intense at higher centres, it lacks pressor activity, there is no post-excitement depression, and it does not depress the desire for food as occurs with amphetamine. The drug however is enhancing the existing pathologic behavior such as exacerbating pre-existing anxiety and is considered the drug of abuse. Meratran has certain indications and contraindications. Indications are schizophrenics without delusions having restriction of interest and activity and with depressant features, psycho-motor retardation and/or blocking of communication, long-term hospitalized schizophrenics with severe deterioration while contraindications are patients with delusions, anxiety, disturbed patients with cerebral arteriosclerosis. Pipradrol was made illegal in many countries in 1970s due to its abuse potential. It is classified under the Misuse of Drugs Act as a Class C substance. The combination of pipradrol with multivitamins and minerals marketed as Alertonic Elixir is used as adjunctive therapy in combating fatigue resulting from emotional or nutritional causes.

Nylidrin (Buphenine, Arlidin) is a beta-adrenergic agonist. Nylidrin causes peripheral vasodilation, a positive inotropic effect, and increased gastric volume of gastric juice. It is used in the treatment of peripheral vascular disorders and premature labor. In peripheral vascular disorders, Arlidin (nylidrin HCl) increases walking ability and promotes healing of trophic ulcers. Nylidrin hydrochloride acts predominantly by beta-receptor stimulation. Beta stimulation with nylidrin has been demonstrated in a variety of isolated tissues from rabbits, guinea pigs and dogs. It has been shown to dilate arterioles in skeletal muscle and to increase cardiac output in the anesthetized dog and cat and in unanesthetized man. An increase in cerebral blood flow and a decrease in vascular resistance has also been reported. The result of this combination of actions is a greater blood supply to ischemic tissues, with usually minimal change in blood pressure. Arlidin may be of benefit in elderly patients with mild to moderate symptoms that are commonly associated with organic mental disorders. Short-term (3 months’ duration) and long-term (12 months’ duration) clinical studies have demonstrated a modest improvement in ability to perform general activities of daily living, self-care and in a capability for social interactions. The mechanism whereby nylidrin may provide relief of selected symptoms in some elderly patients with organic brain disorders is not known.

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.

Methoxamine is an alpha-adrenergic agonist that induces prolonged peripheral vasoconstriction, and can also stimulate the release of arginine vasopressin in humans. In clinical trials, methoxamine was found to improve fecal incontinence. It had been marketed by Glaxo-Smith-Kline under the brand name Vasoxyl but has been discontinued. Methoxamine was also found to stimulate the induction of hiPSC-derived hepatoblasts to ALBUMIN+ cells.