Phenobarbital

Norm   
Therapeutic concentration 65–172µmol/l
Toxic concentration more than 194µmol/l

Synonyms: Luminal^®, Luminalum, Phenaemal^®, Phenaemaletten^®
Serum
Red cap

In adults, the half-life of barbiturates is 96 hours. It is shorter for children – 62 hours, for newborns – 103 hours. The steady-state concentration of the drug in the blood is achieved after 3–4 weeks of treatment. Phenobarbital (phenobarbital) is a sedative and anticonvulsant drug. Monitoring of phenobarbital concentration in the blood is performed in patients with epilepsy who are continuously treated with this drug. It is taken per os. The drug is completely absorbed in the small intestine. The maximum concentration in the blood is reached a few hours after a single dose. Approximately 50% of the unchanged drug is excreted through the kidneys. The drug concentration is first determined two hours after intravenous injection. Later, the drug concentration in the blood is determined every 3–4 weeks.

Source | Handbook of Basic Laboratory Tests | Doctor of Medical Sciences Gintaras Zaleskis