In medicine, the abbreviation Rx (often spelled) refers to the Latin word meaning recipe, recipere. A symbol for the term "prescription," which has evolved to indicate "take this medicine
This sign can be seen on many pharmacies and medical facilities. Likewise, you'll find it printed on containers of several pharmaceuticals.
Doctors always write Rx in prescription so as to denote that terms mentioned may represent one or more than one word.
The name "Rx” comes from the glyph for Jupiter. The symbol for Jupiter can be found in The Old Farmer's Almanac on page 42 (2001 edition) under the names as well as characters of the primary planets and aspects. This symbol resembles a fancy number 4, but with the line chart of the top side left part of notation more curved, like the right upper portion of letter R.
To get to Rx, where R's tail is intersected by the x, you just have to use your imagination a little. The x still hangs far below the R's tail in many modern pharmacy signs. Several mediaeval doctors and herbalists thought that the planets had some sort of influence over human health and the effectiveness of certain plants and shrubs employed in treatment.
These astronomical influences are clear in the recommendations given by the English naturalist Nicholas Culpeper in his publications from the 16th century. As a result of Jupiter's prominence in the healing process (possibly due to its size), the planet's symbol is now commonly used to denote pharmaceutical manufacturers and prescription drugs. The ancients believed the gods who ruled over the planets were an integral part of the planets themselves. So, the Rx symbol truly conveys, "Under the good graces of Jove, the deity of medicines, consume the following substances in the quantities indicated forth," as stated by experts.