Caffeine

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Cat Number

PIPE-0778

CAS Number

58-08-2

For research use only. We do not supply to patients.

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Product Detail Description Scientific Support Advanced Innovations Customer Q&A

CAS Number

58-08-2

EINECS

200-362-1

Storage

Store at room temperature

Synonyms

Guaranine; 1,3,7-Trimethylxanthine; Methyltheobromine; Theine

Molecular Formula

C8H10N4O2

Molecular Weight

194.19

Smiles

CN1C=NC2=C1C(=O)N(C(=O)N2C)C

Appearance

White crystalline powder

Melting Point

234-238℃

Boiling Point

178℃

Relative Density

1.23

General Description

Caffeine is a naturally occurring methylxanthine alkaloid found in coffee, tea, and numerous plants, recognized as the world's most widely consumed psychoactive substance. The compound is highly lipid-soluble, allowing rapid distribution across the blood-brain barrier.

Mechanism of Action

Caffeine acts primarily as a non-selective antagonist of adenosine A1 and A2A receptors, blocking the sedative and vasodilatory effects of endogenous adenosine. This antagonism leads to increased release of neurotransmitters such as dopamine, norepinephrine, and acetylcholine. The result is central nervous system stimulation, including enhanced alertness, improved reaction time, and decreased perception of fatigue.

Application

Beyond its well-known role in combating drowsiness and enhancing mental focus, caffeine is FDA-approved for the treatment of apnea of prematurity in neonates, where it reduces the frequency of breathing pauses. It is also added to over-the-counter analgesics to improve pain relief, particularly for tension headaches and migraine. Caffeine citrate is the preferred formulation in preterm infants due to its favorable pharmacokinetics and safety profile.

This review of peer‑reviewed literature (1975–2021) analyzes caffeine’s mechanisms of action in animal models. By blocking adenosine receptors, caffeine causes tachycardia with potential arrhythmogenic risk via unopposed β1 stimulation. In lung tissue, caffeine inhibits hyperoxia‑induced inflammation, decreasing pro‑inflammatory cytokine expression and preventing functional and structural changes. Beyond its well‑known central nervous system effects, caffeine provides tissue protection, particularly anti‑inflammatory actions in the lung.

Fig. 1 Effects of caffeine on pneumocytes. (Villanueva-García D, et al., 2021)

References

Villanueva-García D, et al. Caffeine: cardiorespiratory effects and tissue protection in animal models. Exp Anim. 2021;70(4):431-439.

In 32 young males, the acute effects of caffeine (vs. placebo) on autonomic control and cardiorespiratory parameters were assessed after 30 minutes of treadmill exercise at 60% VO₂peak, followed by 60 minutes of recovery. Caffeine significantly delayed the recovery of RMSSD and SD1 (time‑domain parasympathetic indices) compared to placebo. Systolic blood pressure differences persisted longer with caffeine, and diastolic blood pressure was affected only in the caffeine protocol. However, caffeine did not influence respiratory rate, oxygen saturation, or frequency‑domain heart rate variability indices. The authors conclude that caffeine delays parasympathetic recovery but has limited overall impact on post‑exercise autonomic regulation.

Fig. 2 Flowchart sample loss during the study. (Gonzaga LA, et al., 2017)

References

Gonzaga LA, et al. Caffeine affects autonomic control of heart rate and blood pressure recovery after aerobic exercise in young adults: a crossover study. Sci Rep. 2017;7(1):14091.

Does Caffeine require special storage conditions for long-term stability?

Caffeine is chemically stable under normal conditions. Store in tightly sealed containers in a cool, dry place, protected from strong odors as it can absorb them.

What is the recommended storage temperature for Caffeine?

Store at controlled room temperature (15-25°C). It is thermally stable, but avoid excessive heat above 40°C to prevent sublimation (loss of material by vaporization).

Is Caffeine hygroscopic, and how does this affect its physical properties?

The anhydrous form is slightly hygroscopic and may form the monohydrate under high humidity (>70% RH), which can affect flowability. Store with desiccant if needed.

How is the impurity theobromine or theophylline controlled in Caffeine API?

These related xanthine impurities are quantified using a validated HPLC method, ensuring they remain below pharmacopoeial (USP/EP) limits.