Tripelennamine (sold as Pyribenzamine by Novartis) is a drug that is used as an antipruritic and first-generation antihistamine. Histamine acting on H1-receptors produces vasodilatation, hypotension, flushing, headache, tachycardia, and bronchoconstriction. Histamine also increases vascular permeability and potentiates pain. Tripelennamine can be used in the treatment of asthma, hay fever, rhinitis, and urticaria, but is now less common as newer antihistamines have replaced it.

Alverine is a smooth muscle relaxant used for the treatment irritable bowel syndrome. Alverine may increase calcium influx during action potentials due to inhibition of the inactivation of L-type calcium channels, but may also suppress evoked activity by inhibiting the sensitivity of contractile proteins to calcium.

Thimerosal is organomercury antiseptic and antifungal agent, used as a preservative in vaccines, immuloglobulins, nasal sprays, contact lens solutions. In USA, European Union countries thiomersal is no longer used in childhood vaccines due to public fears, although the FDA review of 1999 foud no evidence of harm from the use of thimerosal as a vaccine preservative, other than local hypersensitivity reactions. Thimerosal was used as a component of topical antiseptic solution and antiseptic ointment for treating cuts, nasal sprays, eye solutions, vaginal spermicides, diaper rash treatments, but re-evaluation of the drug in 1980-s demonstrated ineffectiveness and toxicity in topical pharmaceutical products, and topical thimerosal was withdrawn from the market. The mechanism of action of thimerosal has not been fully elucidated. It is believed that thimerosal inhibits sulfhydryl-containing active site of various enzymes and binds to sulfhydryl compounds, such as glutathione, cysteine, and SH groups of protein. In addition, thimerosal activates the InsP3 calcium channel on endoplasmic reticular membrane, thereby triggering the release of calcium from intracellular stores resulting in a calcium-induced calcium-influx of extracellular calcium. Consequently, thimerosal may induce or inhibit cellular functions dependent on calcium signaling.

Methapyrilene is an antihistamine and anticholinergic of the pyridine chemical class which was developed in the early 1950s. It was sold under the trade names Co-Pyronil and Histadyl EC. It has relatively strong sedative effects, to the extent that its primary use was as a medication for insomnia rather than for its antihistamine action. Together with scopolamine, it was the main ingredient in Sominex, Nytol, and Sleep-Eze. It also provided the sedative component of Excedrin PM. Manufacturers voluntarily withdrew methapyrilineb drug products from the market in May and June 1979, when methapyrilene was demonstrated to cause liver cancer in rats when given chronically.

Alverine is a smooth muscle relaxant used for the treatment irritable bowel syndrome. Alverine may increase calcium influx during action potentials due to inhibition of the inactivation of L-type calcium channels, but may also suppress evoked activity by inhibiting the sensitivity of contractile proteins to calcium.

Alverine is a smooth muscle relaxant used for the treatment irritable bowel syndrome. Alverine may increase calcium influx during action potentials due to inhibition of the inactivation of L-type calcium channels, but may also suppress evoked activity by inhibiting the sensitivity of contractile proteins to calcium.

Mephenytoin is an antiepileptic drug which can be useful in the treatment of epilepsy. The primary site of action appears to be the motor cortex where spread of seizure activity is inhibited. Possibly by promoting sodium efflux from neurons, mephenytoin tends to stabilize the threshold against hyperexcitability caused by excessive stimulation or environmental changes capable of reducing membrane sodium gradient. This includes the reduction of posttetanic potentiation at synapses. Loss of posttetanic potentiation prevents cortical seizure foci from detonating adjacent cortical areas. Mephenytoin reduces the maximal activity of brain stem centers responsible for the tonic phase of tonic-clonic (grand mal) seizures. The mechanism of action of mephenytoin is not definitely known, but extensive research strongly suggests that its main mechanism is to block frequency-, use- and voltage-dependent neuronal sodium channels, and therefore limit repetitive firing of action potentials. Mephenytoin is no longer available in the US or the UK. It is still studied largely because of its interesting hydroxylation polymorphism.

Benzethonium chloride, also known as hyamine, is a synthetic quaternary ammonium salt. It has surfactant, antiseptic, and anti-infective properties and it is used as a topical antimicrobial agent in first aid antiseptics. It is also found in cosmetics and toiletries such as mouthwashes, anti-itch ointments, and antibacterial moist towelettes. Benzethonium chloride exhibits a broad spectrum of microbiocidal activity against bacteria, fungi, mold and viruses. The US Food and Drug Administration (FDA) specifies that the safe and effective concentrations for benzethonium chloride are 0.1-0.2% in first aid products. Aqueous solutions of benzethonium chloride are not absorbed through the skin. It is not approved in the US or Europe for use as a food additive. Being a quaternary ammonium salt, it is more toxic than negatively charged surfactants. However, in a two-year study on rats, there was no evidence of carcinogenic activity. Benzethonium chloride was characterized as a novel anticancer compound possessing both in vitro and in vivo efficacy justifying further investigation.

Benzethonium chloride, also known as hyamine, is a synthetic quaternary ammonium salt. It has surfactant, antiseptic, and anti-infective properties and it is used as a topical antimicrobial agent in first aid antiseptics. It is also found in cosmetics and toiletries such as mouthwashes, anti-itch ointments, and antibacterial moist towelettes. Benzethonium chloride exhibits a broad spectrum of microbiocidal activity against bacteria, fungi, mold and viruses. The US Food and Drug Administration (FDA) specifies that the safe and effective concentrations for benzethonium chloride are 0.1-0.2% in first aid products. Aqueous solutions of benzethonium chloride are not absorbed through the skin. It is not approved in the US or Europe for use as a food additive. Being a quaternary ammonium salt, it is more toxic than negatively charged surfactants. However, in a two-year study on rats, there was no evidence of carcinogenic activity. Benzethonium chloride was characterized as a novel anticancer compound possessing both in vitro and in vivo efficacy justifying further investigation.