Question
Posted on: March 6 2013Suppositories with pentobarbital.
We have received in the pharmacy a prescription for Nembutal (= pentobarbitalsodium) 60mg Pro Suppo. The preparation in itself is not a problem but can pentobarbitalsodium be absorbed in the rectum? I believe that phenobarbitalsodium cannot be absorbed in the intestine by the local pH.
Answer
Below you'll find two abstracts of publications on this subject.
Phenobarbital was administered to five patients, eight to 20 years of age, by four different administration routes: Intravenous, intramuscular, oral, and rectal. At each administration, extent of bioavailability, elimination rate constant, absorption rate constant, and volume of distribution of or were calculated using a one-compartment open model. The results obtained suggest that rectal administration of or is more reliable than intramuscular or oral administration of the drug for rapid treatment in children.
68 Infants received 7--15 mg or and sodium-or/kg body weight by suppositories of different melting-points and hydroxyl-values (Witepsol H 12, W 35, E 76). The kinetic analysis of the serum concentration curve shows that the rate of rectal absorption is significantly increased if sodium-or instead of or is applied. The absorption rate is faster using suppositories with a lower melting-point (32.5 degrees C) compared to suppositories with a higher one (37.5 degrees C). Increasing The amount of hydroxyl values in the vehicle the absorption rate of or becomes faster. Comparing the area under the serum concentration curve after intravenous and rectal application in 8 infants the absorption ratio was 74%.