Barbiturates list is explained in detail in this article. Thiopentone is prepared commercially from highly alkaline solutions as sodium salt that is readily soluble in water or saline. It is supplied as a yellowish, hygroscopic powder. The pH of a 2.5% solution of thiopental is 10.5.
The properties of commercial preparations of barbiturates list are due to their highly alkaline pH. No other bacteriostatic agent is added; therefore, extreme care in preparation and handling should be exercised at all times to prevent the introduction of microbial contaminants.
Any solution of thiopental sodium with a visible precipitate should not be administered. The stability of pentbthal solutions depends upon several factors, including the diluent, temperature of storage and the amount of carbon dioxide from room air that gains access to the solution.
Any factor or condition which tends to lower pH (increase acidity) of thiopental solutions will increase the likelihood of precipitation of thiopental acid. Such factors include the use of diluents which are too acidic and the absorption of carbon dioxide which can combine with water to form carbonic acid.
Commercial preparations of barbiturates list often contain a mixture of six parts anhydrous sodium carbonate to prevent precipitation of the insoluble acid form of the thiopentone by atmospheric carbon dioxide.
Solutions of succinyicholine, tubocurarine or other drugs which have an acid pH such as opioids, catecholamines, and neuromuscular-blocking drugs, should not be mixed to prevent precipitations.
The powder form of thiopental is stable at room temperature indefinitely. The barbiturates list the solutions should be freshly prepared and used promptly; when reconstituted for administration to several patients, unused portions should be discarded after 24 hours.
At room temperature (22°C), reconstituted solutions ofthiopental remain stable and sterile for at least 6 days (Haws et al, 1998). Sterilization by heating should not be attempted. Sterile water, 5% dextrose, and 0.9% sodium chloride solutions are used for reconstitution.
Also for barbiturates list , the thiopentone commercially available only as racemic mixture, although the S(-) isomers of thiopental is twice as potent as the R(+) isomers.
Thiopental is usually prepared for clinical use in 2.5% solutions. A 5% solution is not recommended. 2.5% thiopental is less associated with venous thrombosis or pain than its 5% solution.
Pentathal or Phenobarbital tops the Barbiturates list of most commonly used drugs.