Drug absorption in spinal cord injury.

The absorption characteristics of drugs in spinal cord injury (SCI) were studied using an actively transported drug [riboflavin (RBF)] and a passively absorbed drug [acetaminophen (ACE)]. RBF absorption was studied following oral administration of 150mg RBF as 5'-phosphate flavin mononucleotide in ten clinically complete quadriplegic patients (C1 to C7, two to 15 months post-onset) and six control subjects matched for age, sex, and weight. Urinary excretion was measured under fasting (F) and nonfasting (NF) conditions for time to peak, peak excretion rate, and percent dose recovered. The results showed a significant difference (p less than 0.05) for all parameters between F and NF conditions for both the SCI and able-bodied groups. However, there was no significant difference for the same parameters between the two groups. ACE absorption was studied in five SCI clinically complete quadriplegic patients (C1 to C7, two to 15 months post-onset following the administration of a 650mg tablet. Serum samples were analyzed for ACE content and showed: time of peak, 1.35 +/- 0.6hr; maximum serum level, 6.8 +/- 2.68 micrograms/ml; half-life, 2.89 +/- 1.81hr; absorption lag time, 18.1 +/- 1.8min; area under the serum level-time curve, 21.8 +/- 6.7 micrograms/.hr/ml. When compared to able-bodied population data in the literature, there was a significant increase in the time to peak and lag time, and a decrease in the maximum ACE serum concentration obtained.(ABSTRACT TRUNCATED AT 250 WORDS)