title: Absorption rate of methylxanthines following capsules, cola and chocolate.
abstract: OBJECTIVE
  To compare caffeine and theobromine absorption after oral administration of capsules, cola beverage and chocolate candy.
  
  
  METHODS
  Three males and four females who abstained from methylxanthines received five methylxanthine-containing treatments: caffeine in capsules (72 mg), administered twice; theobromine in capsules (370 mg); cola beverage (72 mg caffeine) and chocolate candy (72 mg caffeine and 370 mg theobromine). Plasma methylxanthine levels were assayed from samples collected before and 0.25, 0.50, 0.75, 1.0, 1.5, 2.0, and 3.0 h after caffeine capsule and cola treatments and, additionally, at 4.0 and 6.0 h after theobromine capsule and chocolate treatments.
  
  
  RESULTS
  Caffeine plasma concentrations increased rapidly and peaked at approximately 30 min following both capsule treatments 1 (Cmax: 1.93 micrograms.ml-1); and 2 (Cmax: 2.05 micrograms.ml-1). Relative to capsules, caffeine absorption from cola and chocolate was delayed and produced lower maximum caffeine plasma concentrations which peaked 1.5-2.0 h after treatment (For cola, Cmax: 1.57 micrograms.ml-1); and for chocolate, Cmax: 1.50 micrograms.ml-1. Theobromine plasma concentrations peaked approximately 3 h after capsule administration (Cmax: 6.72 micrograms.ml-1). Relative to capsules, theobromine absorption from chocolate was more rapid and produced higher maximum theobromine plasma concentrations which peaked approximately 2 h after treatment (Cmax: 8.05 micrograms.ml-1).
  
  
  CONCLUSIONS
  The results suggest that a usual dietary portion of the cola or chocolate used in this study would produce behaviorally discriminable plasma levels of caffeine in most subjects and of theobromine in at least one subject.
authors.affiliation: Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21224, USA.
authors.forename: G K
authors.initials: GK
authors.lastname: Mumford
authors.forename: N L
authors.initials: NL
authors.lastname: Benowitz
authors.forename: S M
authors.initials: SM
authors.lastname: Evans
authors.forename: B J
authors.initials: BJ
authors.lastname: Kaminski
authors.forename: K L
authors.initials: KL
authors.lastname: Preston
authors.forename: C A
authors.initials: CA
authors.lastname: Sannerud
authors.forename: K
authors.initials: K
authors.lastname: Silverman
authors.forename: R R
authors.initials: RR
authors.lastname: Griffiths
mesh_terms: D000042:Absorption; D000328:Adult; D002099:Cacao; D002110:Caffeine / Q000008:administration & dosage / Q000493:pharmacokinetics*; D002214:Capsules; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D014677:Pharmaceutical Vehicles; D013805:Theobromine / Q000008:administration & dosage / Q000493:pharmacokinetics*
chemical_list: D002214:Capsules; D014677:Pharmaceutical Vehicles; D002110:Caffeine; D013805:Theobromine