Mercury

Application

Mercury (Hydrargyrum, Hg) and its compounds are rarely used in pharmacy today because of their toxicity and adverse effects. An exception is alternative medicine, in which mercury is also called mercurius (e.g., Mercurius solubilis, Mercurius vivus). The English name is Mercury or Quicksilver. In the 20th century, mercury compounds were still widely used and contained, for example, in the disinfectant Merfen (phenylmercuriborate = phenylmercury borate).

Structure and properties

Mercury (Hg) is a heavy, silvery-white metal that, unlike other metals, occurs in the liquid state under standard conditions. The melting point is -38.8 °C. Alloys with other metals are called amalgams. Mercury has a high density of 13.5 g/cm

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. It begins to vaporize already at room temperature. The vapors are toxic and should not be inhaled. Mercury occurs elementally, in the form of salts and in organic compounds. For example, the pharmacopoeia lists mercuric chloride (mercury(II) chloride, hydrargyri dichloridum, HgCl

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) monographed. For example, it exists as a white crystalline powder and is soluble in water. Other salts include mercury oxide, mercury sulfide, mercury nitrate, mercury cyanide, and mercury acetate. Mercury sulfide occurs in the mineral cinnabar (cinnabarite) and has an intense red color.

Effects

Mercury and its salts have antiseptic and protein precipitating properties.

Indications for use

Mercury and its compounds are rarely used today for the following indications. They are considered obsolete (outdated and obsolete):

Adverse effects

Mercury is toxic and must be handled with precautions. Toxicity depends on the compound and the site of administration. For example, the cardiovascular system, respiratory system, digestive tract, nervous system, skin and mucous membranes, liver, kidneys, muscles, and reproductive organs may be affected by poisoning.