Novel methylxanthine derivative-mediated anti-inflammatory effects in inflammatory bowel disease

Table 2 Major biological effects of methylxanthine derivatives

Compound	Molecular weight (g/mol)	Biological effects	Side effects
Caffeine	194.19	Increases alertness, slightly increases metabolic rate[80], increases blood pressure, is a diuretic, improves sports performance[81]	Caffeine dependency, restlessness, insomnia, and anxiety at high levels (250-500 mg daily[82])In extreme amounts (> 600 mg daily chronically): Gastrointestinal (GI) disturbance1, irregular/rapid heartbeat, mania, depression, and psychosis[83]
Pentoxifylline	278.31	Improves blood circulation through peripheral blood vessels, prevents nausea/ altitude sickness, improves red blood cell deformability (i.e., sickle cell anemia), reduces blood viscosity, reduces formations of platelet aggregation/thrombus[84]	Irregular heartbeat, chest pain, dizziness, edema in extremitiesAcute toxicity in rats determined at 1772 mg/kg[85]
Theophylline	180.164	Relaxes bronchial smooth muscle, increases heart contractility, rate, and efficiency, increases blood pressure, increases renal circulation, stimulates respiratory center of CNS, treatment for COPD, asthma, infant apnea[86,87]	Interactions with many drug (cimetidine and phenytoin), and causes nausea, arrhythmias, insomnia, irritability, dizziness, seizures and tachyarrhythmias at toxic concentrations (> 20 mg/mL)[86]

¹GI disturbance is marked by nausea, vomiting, abdominal pain, diarrhea, bowel incontinence, and anorexia. COPD: Chronic obstructive pulmonary disease; CNS: Central nervous system.