During the Reign of Terror, which began in July 1793 and lasted thirteen months, Paris was governed by the Committee of Public Safety who oversaw a regime of mass executions and public purges.Prior to the French Revolution, ancient philosophers wrote about tyrannicide, as tyranny was seen as the greatest political threat to Greco-Roman civilization. Medieval philosophers were similarly occupied with the concept of tyranny, though the analysis of some theologians like Thomas Aquinas drew a distinction between usurpers, who could be killed by anyone, and legitimate rulers who abused their power—the latter, in Aquinas view, could only be punished by a public authority. John of Salisbury was the first medieval Christian scholar to defend tyrannicide. Most scholars today trace the origins of the modern tactic of terrorism to the Jewish Sicarii Zealots who attacked Romans and Jews in 1st-century Palestine. They follow its development from the Persian Order of Assassins through to 19th-century anarchists. The "Reign of Terror" is usually regarded as an issue of etymology. The term terrorism has generally been used to describe violence by non-state actors rather than government violence since the 19th-century Anarchist Movement.In December 1795, Edmund Burke used the word "Terrorists" in a description of the new French government called Directory:
At length, after a terrible struggle, the [Directory] Troops prevailed over the Citizens ... To secure them further, they have a strong corps of irregulars, ready armed.
This in turn prevents the release of other allergy chemicals and increases the blood supply to the area, providing relief from the typical symptoms of hay fever. Levocetirizine, (R)-(-)-cetirizine, is essentially a chiral switch of (±)-cetirizine. This enantiomer, the eutomer, is more selective and less sedative and the (S)-counterpart, the distomer, is inactive. Chemistry
Chemically, levocetirizine is the active levorotary enantiomer of cetirizine, also called the l-enantiomer of cetirizine. It is a member of the diphenylmethylpiperazine group of antihistamines. History
Levocetirizine was first launched in 2001 by the Belgian pharmaceutical company UCB (Union Chimique Belge). Society and culture
Availability
On 31 January 2017, the Food and Drug Administration approved an over-the-counter preparation. Levocetirizine had previously received authorization by the FDA as a prescription drug in 2007, having already been brought to market throughout much of Europe. In India, a prescription-only drug containing levocetirizine hydrochloride and montelukast is sold as Crohist MK. Brand names
Preparations of levocetirizine are sold under the following brand names:

Xyzal  in Australia, Austria, Bulgaria, Croatia, Cyprus, Czech Republic, Finland, France, Hungary, India, Ireland (also Rinozal), Italy, Japan, Lithuania, Netherlands, Poland, Portugal, Romania, Taiwan, Thailand, Turkey, The Philippines, Serbia, Singapore, Slovakia, Slovenia, South Africa, Spain, Switzerland and UK. On May 25, 2007, the United States Food and Drug Administration approved Xyzal, where it is co-marketed by Sanofi-Aventis. Zobral in Cyprus
Levobert in India
Xusal in Germany and Mexico
Xozal in Greece
Degraler in Chile
Allevo in Egypt
Zilola, Histisynt, and Xyzal (UCB) in Hungary
Alcet, Curin, and Seasonix in Bangladesh
Vozet and Uvnil in India
T-Day Syrup in Pakistan
Curin in Nepal.