Methylxanthine caffeine. Medical search. Frequent questions

Caffeine is structurally related to other methylxanthines, theophylline, and theobromine. (drugs.com)
All chocolate contains caffeine and theobromine. (vethelpdirect.com)
Chocolate contains methylxanthine compounds known as theobromine and caffeine. (sitstay.com)
Many natural sources of caffeine also contain widely varying mixtures of other xanthine alkaloids , including the cardiac stimulants theophylline and theobromine and other substances such as polyphenols which can form insoluble complexes with caffeine. (wikidoc.org)
The most commonly employed methods for the analysis of coffee and tea cause the extraction of matrix interferents such as the methylxanthines caffeine and theobromine, which hinder the analysis of anthraquinone. (rsc.org)
Theobromine is a methylxanthine compound very similar to caffeine that is present in chocolate. (bigrockanimalclinic.com)
Theophylline is a methylxanthine, a class of molecule similar to the xanthines caffeine and theobromine found in a normal diet. (medscape.com)

SELECTION CRITERIA: We included randomized trials in preterm infants, in which methylxanthines (aminophylline, caffeine, or theophylline) were compared to placebo or no treatment for any indication (i.e. prevention of apnea, treatment of apnea, or prevention of re-intubation). (lu.se)
caffeine levels are approximately 25% of theophylline levels after theophylline administration and approximately 3 to 8% of caffeine administered would be expected to convert to theophylline. (drugs.com)
Adenosine is antagonized competitively by methylxanthines such as caffeine and theophylline, and potentiated by blockers of nucleoside transport such as dipyridamole. (nih.gov)
Various advantages regarding to specificity, simplicity at operation, rapid response, potential miniaturized platform, low power requirement, and relatively low cost of the analysis make DNA-based biosensors great candidates for detection of many targets, including methylxanthine-based drugs, such as theophylline (TP), used for treating respiratory and cardiovascular problems, such as chronic obstructive pulmonary disease. (databasefootball.com)
Theophylline is metabolized in the liver by the hepatic P450 system enzymes CYP1A2 and CYP3A4 into its metabolites 1,3-dimethyluric acid, 1-methyluric acid, and 3-methylxanthine before being excreted in the urine. (medscape.com)

Caffeine is a central nervous system (CNS) stimulant of the methylxanthine class. (wikipedia.org)
Caffeine, a central nervous system stimulant, is an odorless white crystalline powder or granule, with a bitter taste. (drugs.com)
Caffeine is a stimulant and diuretic that increases the flow of urine and increases the amount of water taken in by the body. (themocracy.com)
Esgic (butalbital, acetaminophen , and caffeine capsule) is a combination of a barbiturate, a non-salicylate analgesic and antipyretic , and a central nervous system stimulant indicated for the relief of the symptom complex of tension (or muscle contraction) headache. (rxlist.com)
Caffeine is a bitter white crystalline xanthine alkaloid that acts as a psychoactive stimulant drug and a mild diuretic (speeds up urine production) [1] in humans and other animals. (wikidoc.org)
In humans, caffeine is a central nervous system (CNS) stimulant , having the effect of temporarily warding off drowsiness and restoring alertness. (wikidoc.org)
Unlike cocoa, which contains the central nervous-system stimulant caffeine and the muscle stimulant Theo bromine, carob does not contain any stimulating methylxanthines. (asianonlinerecipes.com)
Caffeine is a trimethylxanthine stimulant of the central nervous system found in many infusions (coffee, tea, mate, guarana) in cocoa / chocolate and in cola drinks and in supposedly energy drinks. (e-lactancia.org)

Caffeine and 14 of its metabolites are quantified in urine by use of high performance liquid chromatography-electrospray ionization-tandem quadrupole mass spectrometry (HPLC-ESI-MS/MS) with stable isotope labeled internal standards. (cdc.gov)
This is the first two year cycle that caffeine and caffeine metabolites were measured. (cdc.gov)
Urinary caffeine and caffeine metabolites were measured in a one third subsample of persons 6 years and over. (cdc.gov)
Caffeine and its metabolites have antioxidant activity, scavenging reactive oxygen species. (karger.com)
Objective -To determine the presence of adenosine receptor subtypes A 1 and A 2a in equine forebrain tissues and to characterize the interactions of caffeine and its metabolites with adenosine receptors in the CNS of horses. (avma.org)
35 S]GTPγS exchange revealed that caffeine and its metabolites act as pure adenosine receptor antagonists at concentrations that correspond to A 1 and A 2a receptor binding affinities. (avma.org)
Conclusions and Clinical Relevance -Results of our study affirm the presence of guanine nucleotide binding protein linked adenosine receptors (ie, high-affinity A 1 and A 2a adenosine receptors) in equine forebrain tissues and reveal the antagonistic actions by caffeine and several biologically active caffeine metabolites. (avma.org)
Determination of caffeine and its metabolites in human skin homogenate by high-performance liquid chromatography. (cdc.gov)
A method has been developed for the separation and quantification of caffeine and its metabolites in human skin homogenate. (cdc.gov)

Caffeine is a bitter, white crystalline purine, a methylxanthine alkaloid, and is chemically related to the adenine and guanine bases of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). (wikipedia.org)
Caffeine is an alkaloid from the methylxanthines family. (naturvital.co.uk)

Compared with those who do not use caffeine, intake for caffeine users was associated with less chest pain ( P = 0.0013), less aminophylline administration ( P = 0.0371), lower resting and peak heart rate ( P = 0.0497 and 0.0314, respectively), and lower diastolic blood pressure response ( P = 0.0468). (snmjournals.org)
Specifically, caffeine intake was associated with less aminophylline use and chest pain. (snmjournals.org)

The amount of caffeine in each type of tea varies. (themocracy.com)
For example, caffeine is sometimes added to coffee to increase the amount of caffeine in a cup of coffee. (themocracy.com)
However, it is important to note that each type of tea has a different amount of caffeine per serving. (themocracy.com)
Green and black teas have more than double the amount of caffeine (52 mg vs 24 mg) in 100-ml servings than Thai tea. (themocracy.com)
The amount of caffeine varies depending on the type of Thai tea and also depends on how much time has passed since the leaves were picked. (themocracy.com)
For example, green tea has about half the amount of caffeine (24 mg per 100 ml) as black tea (52 mg per 100 ml). (themocracy.com)
You should read the nutrition label to be aware of the amount of caffeine per serving of coffee. (healthline.com)
That's less than half the amount of caffeine in a regular cup. (healthline.com)
A 3.5-ounce (100-gram) serving of pure cocoa can contain the same amount of caffeine as 2.5 cups of coffee, while milk chocolate contains less. (healthline.com)
There is insufficient evidence on the recommended amount of caffeine during lactation. (e-lactancia.org)

Caffeine acts by blocking binding of adenosine to the adenosine A1 receptor, which enhances release of the neurotransmitter acetylcholine. (wikipedia.org)
Caffeine has a three-dimensional structure similar to that of adenosine, which allows it to bind and block its receptors. (wikipedia.org)
Most of these effects have been attributed to antagonism of adenosine receptors, both A 1 and A 2 subtypes, by caffeine, which has been demonstrated in receptor binding assays and observed at concentrations approximating those achieved therapeutically. (drugs.com)
Caffeine, one of the most consumed central nervous system (CNS) stimulants, is an antagonist of A 1 and A 2A adenosine receptors. (frontiersin.org)
Nowadays, not many reports on DNA-methylxanthines interactions have been published, so we decided to perform an electrochemical and spectrometric study of the interaction of TP with double-stranded (dsDNA) or single-stranded (ssDNA) salmon sperm DNA, guanosine (GMP), or adenosine monophosphates (AMP) using square wave and cyclic voltammetry. (databasefootball.com)
caffeine decreases effects of adenosine by pharmacodynamic antagonism. (medscape.com)
Antagonism of adenosine actions in the equine CNS by these stimulants may be responsible for some central actions of methylxanthine drugs, including motor stimulation and enhanced racing performance. (avma.org)
The direct effects of caffeine on arrhythmogenesis are complex with both potentially arrhythmic effects (including sympathetic activation) and potentially antiarrhythmic effects (including adenosine receptor blockade and antioxidant properties). (msdmanuals.com)

Some people experience sleep disruption or anxiety if they consume caffeine, but others show little disturbance. (wikipedia.org)
In North America, 90% of adults consume caffeine daily. (wikidoc.org)
This is especially important to watch out for if you tend to experience negative side effects when you consume caffeine. (healthline.com)

For example, there is some evidence that yaupon holly ( Ilex vomitoria ) may contain caffeine as well as other chemicals that may have health benefits . (themocracy.com)
Here are 10 common foods and drinks that contain caffeine. (healthline.com)
Cocoa beans contain caffeine, with the amount depending on the percentage of cocoa in the product. (healthline.com)
The gummies contain caffeine, prompting the body to use its stored energy more efficiently. (naspcenter.org)

However, pure powdered caffeine, which is available as a dietary supplement, can be lethal in tablespoon-sized amounts. (wikipedia.org)
Participants in this issue of Policy Forum were asked if they believed FDA was justified in issuing the Warning Letters on pure powdered caffeine and, more broadly, to address FDA's and their own roles in assuring the safety of dietary supplement products on the market. (fdli.org)

Consumption of caffeine after abdominal surgery shortens the time to recovery of normal bowel function and shortens length of hospital stay. (wikipedia.org)
[4] One 2008 study suggested that women consuming 200 milligrams or more of caffeine per day had about twice the miscarriage risk as women who drank none, while another 2008 study found no link between miscarriage and caffeine consumption. (wikidoc.org)
Moderate coffee consumption does not produce significant levels of caffeine in plasma or urine of infants , and may be undetectable or below therapeutic levels in the neonatal period. (e-lactancia.org)
showed that consumption of caffeine equivalent to 2-4 cups of coffee 90 min before regadenoson-stress SPECT myocardial perfusion imaging has the potential to adversely affect diagnostic accuracy ( 10 ). (snmjournals.org)

some authorities recommend that pregnant women limit caffeine to the equivalent of two cups of coffee per day or less. (wikipedia.org)
Each mL contains 20 mg caffeine citrate (equivalent to 10 mg of caffeine base) prepared in solution by the addition of 10 mg caffeine anhydrous to 5 mg citric acid monohydrate, 8.3 mg sodium citrate dihydrate and Water for Injection, USP. (drugs.com)
For example, a 100-gram (3.5-cup) serving of green or black tea has about twice as much caffeine as an equivalent amount of black or green coffee. (themocracy.com)

Mean half-life (T 1/2 ) and fraction excreted unchanged in urine (A e ) of caffeine in infants have been shown to be inversely related to gestational/postconceptual age. (drugs.com)
Caffeine is also a diuretic and can increase urine flow, which has been shown to help with weight loss , as well as lowering blood pressure and increasing blood flow to the heart, which can reduce blood pressure. (themocracy.com)
Caffeine is cleared through metabolism and excretion in the urine. (nih.gov)

Our Esgic (butalbital, acetaminophen, and caffeine capsule) Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication. (rxlist.com)
Butalbital, acetaminophen and caffeine are supplied in capsule form for oral administration. (rxlist.com)
Esgic ® Capsules (butalbital, acetaminophen and caffeine capsules USP 50 mg/325 mg/40 mg) are indicated for the relief of the symptom complex of tension (or muscle contraction) headache. (rxlist.com)
It consists of a fixed combination of butalbital, acetaminophen and caffeine. (nih.gov)

Caffeine is also found in cocoa beans, guarana berries, kola nuts, maté leaves, yerba mate leaves, and various other plants such as yaupon holly. (themocracy.com)
The most commonly used caffeine-containing plants are coffee , tea , and to a lesser extent [9] cocoa . (wikidoc.org)

Caffeine is used as a primary treatment for apnea of prematurity, but not prevention. (wikipedia.org)
Although methylxanthines are widely used to prevent and treat apnea associated with prematurity and to facilitate extubation, there is uncertainty about the benefits and harms of different types of methylxanthines. (lu.se)
OBJECTIVES: To assess the effects of methylxanthines on the incidence of apnea, death, neurodevelopmental disability, and other longer-term outcomes in preterm infants (1) at risk for or with apnea, or (2) undergoing extubation. (lu.se)
Only the Caffeine for Apnea of Prematurity (CAP) study (enrolling 2006 infants) reported on this outcome. (lu.se)
Although the mechanism of action of caffeine in apnea of prematurity is not known, several mechanisms have been hypothesized. (drugs.com)
Apnea, the absence of breathing, is the most frequently reported disorder of breathing control in premature infants, and neonatal care units habitually use methylxanthine derivatives such as caffeine to treat these patients who are less than a month old. (sciencedaily.com)
The caffeine group consisted of 11 neonates receiving an oral caffeine citrate treatment for apnea caused by unknown reasons. (sciencedaily.com)

Caffeine citrate is on the WHO Model List of Essential Medicines. (wikipedia.org)
In the presence of citric acid it forms caffeine citrate salt in solution. (drugs.com)
The structural formula and molecular weight of caffeine citrate follows. (drugs.com)
Caffeine citrate should be administered with caution in preterm neonates with impaired renal or hepatic function. (drugs.com)
Serum concentrations of caffeine should be monitored and dose administration of caffeine citrate should be adjusted to avoid toxicity in this population. (drugs.com)
A 1 mL/kg (20 mg/kg caffeine citrate providing 10 mg/kg as caffeine base) loading dose of caffeine citrate was administered intravenously, followed by a 0.25 mL/kg (5 mg/kg caffeine citrate providing 2.5 mg/kg of caffeine base) daily maintenance dose administered either intravenously or orally (generally through a feeding tube). (drugs.com)

Because caffeine overdoses, intentional or unintentional, are relatively common in the United States, physicians and other medical personnel must be aware of caffeine toxicity to recognize and treat it appropriately. (medscape.com)
The thyroid should be examined because thyrotoxicosis may mimic caffeine toxicity. (medscape.com)
Laboratory studies are indicated in patients with moderate-to-severe symptoms of caffeine toxicity. (medscape.com)
The introductory overview also provides background on caffeine, including how much Americans consume daily, differences in how individuals respond to caffeine, how the body processes caffeine, and what is known about its toxicity. (fdli.org)

After oral administration of 10 mg caffeine base/kg to preterm neonates, the peak plasma level (C max ) for caffeine ranged from 6 to 10 mg/L and the mean time to reach peak concentration (T max ) ranged from 30 minutes to 2 hours. (drugs.com)
Caffeine levels in the cerebrospinal fluid of preterm neonates approximate their plasma levels. (drugs.com)
Caffeine metabolism in preterm neonates is limited due to their immature hepatic enzyme systems. (drugs.com)
Studies examining the pharmacokinetics of caffeine in neonates with hepatic or renal insufficiency have not been conducted. (drugs.com)
Currently, pharmacologic treatment for these neonates is typically limited to caffeine or other methylxanthines. (biospace.com)
As these adults consume their coffee, they do so unaware that some of the youngest Americans are also getting a treatment of caffeine -- not to stay awake, but to assist in treating a major sleep disorder found in some neonates. (sciencedaily.com)
These receptors are believed to be an important target for caffeine action in premature neonates. (sciencedaily.com)
The question of an increase in peripheral chemoreceptor responsiveness (associated or not with a direct, central action of caffeine) remains debatable, particularly in human neonates. (sciencedaily.com)
Now a team of French physiologists has conducted a study to (1) assess whether caffeine treatment in premature neonates stimulates ventilation through peripheral chemoreceptors and (2) determine the potential influence of sleep states. (sciencedaily.com)
After three weeks of treatment, the neonates were compared with a control group (11 neonates not undergoing caffeine therapy) matched for age and body mass. (sciencedaily.com)

Black tea contains 2% to 4% caffeine, which affects thinking and alertness. (medlineplus.gov)

Caffeine is also found in various foods and beverages like chocolate, cola soft drinks, energy drinks, medications, teas, and foods such as bananas. (themocracy.com)
Cats weigh so little that even white chocolate can sometimes cause disease, despite the low levels of methylxanthines. (vethelpdirect.com)

In this study, we investigated the potential protective effects of this methylxanthine in the retinal tissue. (frontiersin.org)
We tested caffeine by using in vitro and in vivo paradigms of retinal inflammation. (frontiersin.org)
Human retinal pigment epithelial cells (ARPE-19) were exposed to lipopolysaccharide (LPS) with or without caffeine. (frontiersin.org)
Finally, the ischemia reperfusion (I/R) injury model was used in C57BL/6J mice to induce retinal inflammation and investigate the effects of caffeine treatment. (frontiersin.org)
In conclusion, these findings suggest that caffeine is a good candidate to counteract inflammation in retinal diseases. (frontiersin.org)
we investigated caffeine by using in vitro and in vivo paradigms of retinal inflammation. (frontiersin.org)

People may drink beverages containing caffeine to relieve or prevent drowsiness and to improve cognitive performance. (wikipedia.org)
Some people use caffeine-containing beverages such as coffee or tea to try to treat their asthma. (wikipedia.org)
Beverages containing caffeine, such as coffee , tea , soft drinks and energy drinks enjoy great popularity. (wikidoc.org)

The best-known source of caffeine is the coffee bean, the seed of the Coffea plant. (wikipedia.org)
The world's primary source of caffeine is the coffee bean (the seed of the coffee plant ), from which coffee is brewed. (wikidoc.org)
Tea is another common source of caffeine. (wikidoc.org)
It was once a main flavoring agent and source of caffeine in commercial colas like Coca-Cola. (healthline.com)
The kola nut is the seed of the kola tree and a natural source of caffeine ( 1 , 2 , 3 , 12 ). (healthline.com)

It is also important to note that other types of teas such as maté, yerba mate, guarana, and kola nut can have even higher amounts of caffeine than green and black teas. (themocracy.com)
However, coffee products may contain very different amounts of caffeine. (healthline.com)
Coffee is a brewed beverage that naturally contains varying amounts of caffeine, depending on the serving size and product brand. (healthline.com)

In consideration of the complex pharmacological profile of this drug, the effects of caffeine are not straightforward to be predicted ( Dai and Zhou, 2011 ), and although the current literature provides some evidence regarding the effects of caffeine in the CNS, few studies were carried out regarding its actions in the eye. (frontiersin.org)
When one also considers the indirect effects of caffeine and the possibility of effects of other active ingredients in coffee, it quickly becomes evident that prediction of the effects of habitual coffee ingestion on the propensity to tachyarrhythmias, in the general population or in a specific individual, is not possible. (msdmanuals.com)

Other, less commonly used, sources of caffeine include the yerba mate [10] and guarana plants, which are sometimes used in the preparation of teas and energy drinks. (wikidoc.org)

A cup of coffee contains 80-175 mg of caffeine, depending on what "bean" (seed) is used, how it is roasted, and how it is prepared (e.g., drip, percolation, or espresso). (wikipedia.org)
Although Thai tea is not a coffee plant, it has caffeine like other teas. (themocracy.com)
He coined the term "kaffein", a chemical compound in coffee, which in English became caffeine. (wikidoc.org)
[7] High caffeine levels have also been found in the surrounding soil of coffee bean seedlings. (wikidoc.org)
It is therefore understood that caffeine has a natural function as both a natural pesticide and as an inhibitor of seed germination of other nearby coffee seedlings [8] thus giving it a better chance of survival. (wikidoc.org)
Generally, dark-roast coffee has less caffeine than lighter roasts because the roasting process reduces the bean's caffeine content. (wikidoc.org)
[15] [16] Arabica coffee normally contains less caffeine than the robusta variety. (wikidoc.org)
On average, an 8-ounce (240-mL) cup of coffee contains about 100 mg of caffeine. (healthline.com)
At this level, 4 cups of coffee per day will keep you within the safe limit of 400 mg of caffeine for healthy adults. (healthline.com)
In case you're wondering, decaffeinated coffee still contains caffeine. (healthline.com)
One cup (240 mL) of decaf coffee contains 1-50 mg of caffeine, depending on the brand and serving size. (healthline.com)
Every morning, millions of adults consume voluminous cups of coffee, seeking the jolting effect of caffeine. (sciencedaily.com)
A cup of coffee can contain between 0.10 and 0.25g of caffeine, depending on the mixture and the method of preparation. (naturvital.co.uk)
As well as in the coffee grains of the fruits of the Coffea arabica L tree, caffeine is a substance that is present in other plans, such as cacao, guarana, tea or the cola nut. (naturvital.co.uk)
With respect to biological plausibility, the major, although not the only, pharmacologically active constituent of coffee is the methylxanthine caffeine. (msdmanuals.com)
Don't confuse black tea with other caffeine sources, including coffee, oolong tea, and green tea. (medlineplus.gov)
Coffee, tea, mate, methylxanthines and methylglyoxal / this publication represents the views and expert opinions of an IARC Working Group on the Evaluation of Carcinogenic Risks to Humans which met in Lyon, 27 February to 6 March 1990. (who.int)

Like most xanthines, caffeine is rapidly absorbed and distributed in all body tissues and fluids, including the CNS, fetal tissues, and breast milk. (nih.gov)

Caffeine may help boost metabolism or speed up fat burning so that more calories are burned off, which can lead to weight loss . (themocracy.com)

Caffeine can produce a mild form of drug dependence - associated with withdrawal symptoms such as sleepiness, headache, and irritability - when an individual stops using caffeine after repeated daily intake. (wikipedia.org)
The aim of our study was to measure caffeine concentrations in vitreous samples after peroral caffeine intake. (karger.com)
However, the effects of daily caffeine intake on regadenoson stress are unknown. (snmjournals.org)
This study assessed the effects of daily caffeine intake on symptoms and hemodynamic changes during stress testing with regadenoson. (snmjournals.org)
Patients presenting for regadenoson stress myocardial perfusion imaging were asked their amounts of daily caffeine intake. (snmjournals.org)
The last intake of caffeine was at least 12 h before the test. (snmjournals.org)
No associations were found between caffeine intake and arrhythmia or systolic blood pressure response. (snmjournals.org)

While this is not FDA's first caffeine action 6,7 or its first demonstration of concern, 8,9 it does highlight the agency's continuing concerns about this stimulatory substance, particularly when caffeine's use as a food product is promoted for use at levels it considers unsafe and/or promoted to vulnerable populations, such as children and adolescents. (fdli.org)
Caffeine is a naturally occurring substance called methylxanthine. (themocracy.com)
Caffeine is the world's most widely consumed psychoactive substance , but unlike most others, it is legal and unregulated in nearly all jurisdictions. (wikidoc.org)
Some yerba mate enthusiasts assert that mateine is a stereoisomer of caffeine, which would make it a different substance altogether. (wikidoc.org)
Caffeine is the most commonly consumed psychostimulant substance in the world. (healthline.com)

It is structurally similar to the nucleobases and other methylxanthines, especially to caffeine. (databasefootball.com)

There is also evidence that caffeine possesses antioxidant properties, which may protect cells against the effects of UV radiation. (cosmeticsandtoiletries.com)

This is a methylxanthine compound, and its chemical properties are very similar to those of caffeine, which is very toxic to dogs and potentially other pets. (animalguardian.org)

Caffeine is the world's most widely consumed psychoactive drug. (wikipedia.org)

Avoid caffeine in any form as it contains methylxanthine that stimulates breast tissue and causes pain. (home-remedies-for-you.com)

The European Food Safety Authority reported that up to 400 mg of caffeine per day (around 5.7 mg/kg of body mass per day) does not raise safety concerns for non-pregnant adults, while intakes up to 200 mg per day for pregnant and lactating women do not raise safety concerns for the fetus or the breast-fed infants. (wikipedia.org)
The mean volume of distribution of caffeine in infants (0.8 to 0.9 L/kg) is slightly higher than that in adults (0.6 L/kg). (drugs.com)
In young infants, the elimination of caffeine is much slower than that in adults due to immature hepatic and/or renal function. (drugs.com)
Consuming up to 400 mg of caffeine per day has not been associated with adverse health effects in healthy adults ( 1 , 2 , 3 ). (healthline.com)

Caffeine is present in most teas and green, black, or oolong teas. (themocracy.com)

It appears that caffeine in low doses improves airway function in people with asthma, increasing forced expiratory volume (FEV1) by 5% to 18% for up to four hours. (wikipedia.org)
Doses greater than 300 - 500 mg of caffeine daily can cause nervousness, irritability and insomnia in the infant (Santos 2012, Martin 2007, Clement 1989, Rustin 1989) , as well as decreased iron levels in breast milk and anemia in the infant (Muñoz 1988) . (e-lactancia.org)

Caffeine is used for both prevention and treatment of bronchopulmonary dysplasia in premature infants. (wikipedia.org)

Serum caffeine concentration determinations do not influence management. (medscape.com)

Habitual use of caffeine should be considered a risk factor for most menstrual abnormalities. (researchgate.net)

Hepatic biotransformation prior to excretion results in about equal amounts of 1-methylxanthine and 1-methyluric acid. (nih.gov)

On August 27, 2015, the US Food and Drug Administration (FDA) issued Warning Letters to five companies selling pure powdered bulk caffeine to consumers as a dietary supplement. (fdli.org)
Its concerns have related to caffeine-containing dietary supplements and energy drinks (a group of products that are marketed both as supplements and conventional food) 10,11,12 as well as to other conventional food, including caffeine-containing confectionary. (fdli.org)

These all contain substances called methylxanthines, which are found in cacao seeds. (dogsmith.com)

It is a methylxanthine derivative with molecular weight of 194.2 Da and Log P o/w of -0.07. (cosmeticsandtoiletries.com)

One review study showed that 300 mg of caffeine per day in healthy pregnant women is safe, with limited data suggesting that 1.1 mg of caffeine per pound (2.5 mg per kg) of body weight in children and adolescents may be safe ( 2 ). (healthline.com)

The aim was to assess whether, and to what extent, changes in rheological properties exerted by these two parameters could affect the in vitro release of caffeine from a hydrogel formulation. (cosmeticsandtoiletries.com)

Caffeine treatment for premature infants is supposed to increase breathing frequency, decrease the number of apneic spells, and reduce partial tension of carbon dioxide (PCO2) and the need for (and duration of) mechanical ventilation. (sciencedaily.com)
One study found no problems in infants whose mothers consumed 500 mg of caffeine daily for 5 days. (e-lactancia.org)

Consuming more than this during pregnancy is possibly unsafe and has been linked to an increased risk of miscarriage, increased risk of sudden infant death syndrome (SIDS), and other negative effects, including symptoms of caffeine withdrawal in newborns and lower birth weight. (medlineplus.gov)

thus, caffeine is typically withheld 12-24 h before stress with regadenoson. (snmjournals.org)

In hemodynamically stable patients with mild symptoms and a clear history of caffeine ingestion, no laboratory studies are indicated. (medscape.com)
The use of regadenoson stress for myocardial perfusion imaging in caffeine consumers is very common, safe, and associated with a lower incidence of certain symptoms than in non-caffeine consumers. (snmjournals.org)

Caffeine also increases cyclic AMP levels through nonselective inhibition of phosphodiesterase. (wikipedia.org)
on the contrary, caffeine treatment maintained physiological levels of BDNF in the retina of I/R eyes. (frontiersin.org)
Caffeine was also able to reduce IL-6 mRNA levels in the retina of I/R eyes. (frontiersin.org)

Anatomy11

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Analytical, Diagnostic and Therapeutic Techniques and Equipment3

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Phenomena and Processes16

Disciplines and Occupations1

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Theobromine7

Theophylline5

Stimulant8

Metabolites9

Alkaloid2

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Amount of caffeine10

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Consume caffeine3

Contain caffeine4

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Apnea7

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Effects of caffeine2

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Coffee17

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