Dalcotidine is a histamine H2 receptor antagonist that demonstrated potent gastric mucosal protective activity on acute gastric lesions and duodenal ulcers. Dalcotidine was discontinued in phase III of clinical trials in Japan.

(-)-Propranolol is a small molecule β-adrenergic receptor antagonist and the active isomer of (±)-Propranolol preparations. (-)-Propranolol blocks the binding of epinephrine, norepinephrine, and other endogenous catecholamines to the β-adrenergic receptor, impeding increases in cardiac flow velocity and general stimulation of the sympathetic nervous system signaled by the association of these molecules to the β-adrenergic receptor. In addition to blockade of agonist binding, antagonism of the β-adrenergic receptor by (-)-Propranolol produces negative chronotropic and inotropic action, effectively dampening the force and rate of cardiac contraction. These negative chronotropic and inotropic effects correlate to a demonstrated suppression of adrenaline-induced cardiac arrhythmia by (-)-Propranolol. Suppression of β-adrenergic receptor activation by (-)-Propranolol has been widely exploited in counteracting situations sensitive to heightened cardiac activity including hypertension, angina pectoris, and cardiac ischemia.

Carazolol is a beta1/beta2 adrenoreceptor blocking agent. Activity and safety of the drug were evaluated in clinical trials that were conducted in healthy subjects and in patients suffering from either chronic bronchitis or asthma. The drug, however, was not developed for human use. Instead, carazolol is used in to reduce stress in animals during transportation. In veterinary medicine, carazolol is given by intramuscular injection to pigs is indicated in stress-inducing situations. In cattle, carazolol is intended to be used for the prevention of shipment stress caused by transportation and formation of new herds.

Chloropyramine is an antagonist of H1 histamine receptors. It is indicated for the treatment of various forms of allergic reactions. Chloropyramine is a drug capable of (1) inhibiting the biochemical function of VEGFR-3 and FAK, (2) inhibiting proliferation of a diverse set of cancer cell types in vitro, and (3) reducing tumor growth in vivo.

Alfurolol is a beta-adrenergic blocker. It is non-selective blocking drug with both intrinsic sympathomimetic activity and weak membrane stabilizing activity. There is also evidence that, unlike other beta-blocking drugs, only extremely small amounts of alfurolol cross the blood-brain barrier: because of this property, it has very little effect on the CNS. Alfurolol consistently produced a reduction in exercise heart rate at all times during the seven-hour period of observation, and the reductions were significantly different from the corresponding values after placebo treatment. Alfurolol is active both on heart rate and systolic pressure.

Clocapramine is a chlorinated derivative of carpipramine. The hydrochloride has been given orally in the treatment of schizophrenia. Clocapramine is an antagonist of the Dopamine D2 and Serotonine (5-HT2) receptors. It has been implicated in at least one strange death, including a suicide. It augments the paroxetine in the panic disorder treatment.

Cyproterone belongs to a group of medications known as steroidal antiandrogens. It suppresses testosterone and its metabolites. It has approximately three-fold lower potency as an antagonist of the androgen receptor relative to cyproterone acetate. Cyproterone acetate is used to treat advanced prostate cancer and acne.

BQ-123 is a selective endothelin receptor-1 antagonist; it is used as a biochemical tool in the study of endothelin receptor function. BQ-123 was suspected to contribute to the regulation of vascular tone humans. However, a study involving young normotensive subjects did not demonstrate any major role for BQ-123 regulation of vascular tone.

Mebhydrolin (INN) or mebhydroline is a histamine H1-receptor antagonist. It is not available in the United States, but it is available in various other countries under the brand names Bexidal and Diazolin. It is used for symptomatic relief of allergic symptoms caused by histamine release, including nasal allergies and allergic dermatosis.

Timepidium bromide is a quaternary ammonium antimuscarinic used for the symptomatic treatment of visceral spasms. It is a muscarinic antagonist.