High Performance Liquid Chromatographic Analysis of Caffeine Concentrations in Plasma and Saliva

Alkaysi, H. N.; Salem, Mutaz S.; El–Sayed, Y. M.

doi:10.1111/j.1365-2710.1988.tb00165.x

Cited by 28 publications

(22 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Each subject provided a saliva sample 2.5 h before the first caffeine/placebo capsule, 5 min before bedtime, and 5 min after wake time. A rapid high-performance liquid chromatographic (HPLC) method was used for the analysis of caffeine in saliva (Alkaysi et al, 1988). The HPLC system consisted of a Spectra SYSTEM pump and a spectra SYSTEM UV detector (Thermoseparation Products Inc.).…”

Section: Methodsmentioning

confidence: 99%

Effects of Caffeine are more Marked on Daytime Recovery Sleep than on Nocturnal Sleep

Carrier

Fernandez‐Bolaños

Robillard

et al. 2006

Neuropsychopharmacol

View full text Add to dashboard Cite

Caffeine is often used to counteract sleepiness generated by sleep deprivation, jet lag, and shift-work, and is consumed at different times of day. Caffeine also has effects on sleep. However, little is known about the interaction between sleep deprivation, circadian timing, and caffeine consumption on sleep. In this study, we compared the effects of caffeine on nocturnal sleep initiated at habitual circadian time and on daytime recovery sleep. Thirty-four moderate caffeine consumers participated in both caffeine (200 mg) and placebo (lactose) conditions in a double-blind crossover design. Seventeen subjects followed their habitual sleep-wake cycle and slept in the laboratory during the night (Night), while 17 subjects were sleep deprived for one night and recovery sleep started in the morning (DayRec). All subjects received a capsule of 100 mg of caffeine (or placebo) 3 h before bedtime, and the remaining dose 1 h before bedtime. Compared to placebo, caffeine lengthened sleep latency, increased stage 1, and reduced stage 2 and slow-wave sleep (SWS) in both groups. However, caffeine reduced sleep efficiency more strongly in the DayRec group, and decreased sleep duration and REM sleep only in that group. The stronger effects of caffeine on daytime recovery sleep compared to nocturnal sleep are probably the consequence of the combined influence of increasing circadian wake propensity drive and the dissipation of homeostatic sleep pressure. We propose that the reduction of SWS by caffeine during daytime sleep increases the impact of the circadian wake signal on sleep. These results have implications for individuals using caffeine during night time. Neuropsychopharmacology (2007) 32, 964-972.

show abstract

Section: Methodsmentioning

confidence: 99%

Effects of Caffeine are more Marked on Daytime Recovery Sleep than on Nocturnal Sleep

Carrier

Fernandez‐Bolaños

Robillard

et al. 2006

Neuropsychopharmacol

View full text Add to dashboard Cite

show abstract

“…Previous research has shown that caffeine concentrations measured in saliva correlate highly with levels measured in blood (Alkaysi et al, 1988). Moreover, because plasma caffeine levels typically increase progressively during the day (due to intermittent consumption of caffeine beverages) and plateau by late afternoon or early evening, the best single-sample bioassay of daily caffeine intake is provided by samples obtained in the late afternoon (Lelo et al, 1986).…”

Section: Salivary Caffeinementioning

confidence: 98%

Effects of dietary caffeine on mood when rested and sleep restricted

James

Gregg

2004

Human Psychopharmacology

View full text Add to dashboard Cite

Prolonged use of caffeine can lead to physical dependence evidenced by characteristic withdrawal symptoms during abstinence. Debate exists as to whether mood enhancement by caffeine represents a net effect or merely the restoration of abstinence-induced mood decrements. One aim of this study was to determine the net effects on mood of dietary caffeine compared with prolonged abstinence. In addition, the study aimed to determine whether caffeine restores mood degraded by a non-caffeine source, namely, sleep restriction. A double-blind placebo-controlled cross-over design was employed in which 48 male and female volunteers alternated weekly between ingesting placebo and caffeine (1.75 mg/kg) three times daily for 4 consecutive weeks, while being either rested or sleep restricted. Mood was assessed using a computerized version of the profile of mood states (POMS), giving scores for overall mood and six mood dimensions. Gender had small effects on mood, whereas all mood dimensions were markedly adversely affected by sleep restriction. Caffeine had no significant net enhancing effects on mood when participants were rested, and produced no net restorative effects when mood was degraded by sleep restriction. On the contrary, caffeine-induced decrements in mood were observed during both conditions of rest and sleep restriction.

show abstract

“…To check compliance with the prescribed caffeine regimen, participants provided a 5-ml sample of saliva at 17.00 h for every day of the 4-week program. Previous research has shown that caffeine concentrations measured in blood and saliva are highly correlated [27]. Moreover, because plasma caffeine levels typically increase progressively during the day (due to intermittent consumption of caffeine beverages) and plateau by late afternoon or early evening, the best single-sample bioassay of daily caffeine intake is provided by samples obtained in the late afternoon [28].…”

Section: Experimental Designmentioning

confidence: 99%

Acute and Chronic Effects of Caffeine on Performance, Mood, Headache, and Sleep

1998

View full text Add to dashboard Cite

Despite being the most widely consumed psychoactive substance in the world, there is considerable confusion regarding the effects of caffeine. This study examined objective indices of performance, and self-reported mood, headache, and sleep in 36 healthy male and female habitual caffeine consumers exposed to a pattern of moderate intake. A double-blind placebo-controlled cross-over design with counterbalancing was employed in which all subjects participated in four experimental conditions involving the ingestion of placebo or caffeine 3 times daily for 6 days followed by a 7th (challenge) day of placebo or caffeine ingestion. No evidence was found that caffeine improved performance, either in the context of acute or habitual use. On the contrary, performance was found to be significantly impaired when caffeine was withdrawn abruptly following habitual use. Participants reported feeling more alert and less tired following acute ingestion of caffeine, but feeling less alert in conjunction with chronic exposure to the drug. In addition, caffeine withdrawal was associated with reported increasses in frequency and severity of headache, and with reports of sleeping longer and more soundly.

show abstract

High Performance Liquid Chromatographic Analysis of Caffeine Concentrations in Plasma and Saliva

Cited by 28 publications

References 7 publications

Effects of Caffeine are more Marked on Daytime Recovery Sleep than on Nocturnal Sleep

Effects of Caffeine are more Marked on Daytime Recovery Sleep than on Nocturnal Sleep

Effects of dietary caffeine on mood when rested and sleep restricted

Acute and Chronic Effects of Caffeine on Performance, Mood, Headache, and Sleep

Contact Info

Product

Resources

About