Over-the-counter (OTC) drugs are medicines sold directly to a consumer without a requirement for a prescription from a healthcare professional, as opposed to prescription drugs, which may be supplied only to consumers possessing a valid prescription. In many countries, OTC drugs are selected by a regulatory agency to ensure that they contain ingredients that are safe and effective when used without a physician's care. OTC drugs are usually regulated according to their active pharmaceutical ingredient (API) and strengths of final products.
Cold medicines are a group of medications taken individually or in combination as a treatment for the symptoms of the common cold and similar conditions of the upper respiratory tract. The term encompasses a broad array of drugs, including analgesics, antihistamines and decongestants, among many others. It also includes drugs which are marketed as cough suppressants or antitussives, but their effectiveness in reducing cough symptoms is unclear or minimal.
Guaifenesin, also known as glyceryl guaiacolate, is an expectorant medication taken by mouth and marketed as an aid to eliminate sputum from the respiratory tract. Chemically, it is an ether of guaiacol and glycerine. It may be used in combination with other medications. A 2014 study found that guaifenesin does not affect sputum volume in upper respiratory infections.
Ethylmorphine is an opioid analgesic and antitussive.
Phenyltoloxamine is an antihistamine with sedative and analgesic effects. It is available in combination with other drugs such as paracetamol (acetominophen).
Dextromethorphan, sold under the brand name Robitussin among others, is a cough suppressant used in many cough and cold medicines. In 2022, the US Food and Drug Administration (FDA) approved the combination dextromethorphan/bupropion to serve as a rapid-acting antidepressant in people with major depressive disorder.
Pentoxyverine (rINN) or carbetapentane is an antitussive commonly used for cough associated with illnesses like common cold. It is sold over-the-counter as Solotuss, or in combination with other medications, especially decongestants. One such product is Certuss, a combination of guaifenesin and pentoxyverine. The drug has been available in the form of drops, suspensions and suppositories.
Dimethoxanate is a cough suppressant of the phenothiazine class.
Cloperastine (INN) or cloperastin, in the forms of cloperastine hydrochloride (JAN) and cloperastine fendizoate, is an antitussive and antihistamine that is marketed as a cough suppressant in Japan, Hong Kong, and in some European countries. It was first introduced in 1972 in Japan, and then in Italy in 1981.
Dropropizine is a cough suppressant that is sold in Germany, Central America, South America, and some African countries such as Congo. It is sold as suppositories, tablets, and syrup. It is used to stop a cough caused by allergies or a cold.
Dibunate is a cough suppressant. As the sodium salt, it has been marketed under the name Becantyl, Becantex, or Linctussal with a dosage of 20 to 30 mg, as either syrup or tablets.
Zipeprol is a centrally acting cough suppressant developed in France in the 1970s. It is not a morphinan derivative. Zipeprol acts as a local anaesthetic and has mucolytic, antihistamine and anticholinergic properties. It is sold with several brand names such as Zinolta and Respilene. It is not available in the United States or Canada and has been discontinued in Europe. It is still available in some countries in Asia and South America.
Butamirate is a cough suppressant. It has been marketed in Europe and Mexico, but not in the United States.
Clobutinol is a cough suppressant formerly distributed by Boehringer Ingelheim and its licensees under the names Lomisat and Silomat, by Bioter as Biotussin, and by Violani-Farmavigor as Pertoxil. It has been withdrawn from the market worldwide.
Benproperine (INN) is a cough suppressant. It has been marketed in multiple countries in Central America and Europe, as the phosphate or pamoate salts in either tablet, dragée, or syrup form. Trade names include Blascorid in Italy and Sweden, Pectipront and Tussafug in Germany, and Pirexyl in Scandinavia. The recommended dosage for adults is 25 to 50 mg two to four times daily, and for children 25 mg once or twice daily. Adverse effects include dry mouth, dizziness, fatigue, and heartburn.
Dimemorfan (INN), or dimemorfan phosphate (JAN), also known as 3,17-dimethylmorphinan, is an antitussive of the morphinan family that is widely used in Japan and is also marketed in Spain and Italy. It was developed by Yamanouchi Pharmaceutical and introduced in Japan in 1975. It was later introduced in Spain in 1981 and Japan in 1985.
Domiodol is a mucolytic and expectorant. It has been marketed in Italy by Maggioni under the trade name Mucolitico Maggioni and sold in syrup, sachet, and tablet form, with a dosage of 60mg three to four times daily in adults. Contraindications include severe renal or hepatic insufficiency.
Eprazinone is a mucolytic and bronchospasm relieving drug. It has been marketed in many European countries, but not in the US or United Kingdom.
Alloclamide is an antitussive and antihistamine drug marketed in Finland and Spain. It has never been marketed in the US.
Dextrofemine, sold under the brand names Marsyl and Dysmalgine, is a uterine spasmolytic and muscle relaxant of the amphetamine family. It is the dextrorotatory enantiomer of racefemine. The drug acts as a β-adrenergic receptor agonist and sympathomimetic. It was marketed in France in 1966 but appears to no longer be marketed. Other tocolytics with similar chemical structures as phenethylamines or amphetamines include bedoradrine, buphenine, fenoterol, hexoprenaline, isoxsuprine, ritodrine, and terbutaline.
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