Pentoxil (Pentoxifylline Extended-release Tablets, USP) is indicated for the treatment of patients with intermittent claudication based on chronic occlusive arterial disease of the limbs. Pentoxil can improve function and symptoms but is not intended to replace more definitive therapy, such as surgical bypass, or removal of arterial obstructions when treating peripheral vascular disease. Pentoxifylline and its metabolites improve the flow properties of blood by decreasing its viscosity. In patients with chronic peripheral arterial disease, this increases blood flow to the affected microcirculation and enhances tissue oxygenation. The precise mode of action of pentoxifylline and the sequence of events leading to clinical improvement are still to be defined. Pentoxifylline inhibits erythrocyte phosphodiesterase, resulting in an increase in erythrocyte cAMP activity. Subsequently, the erythrocyte membrane becomes more resistant to deformity. Along with erythrocyte activity, pentoxifylline also decreases blood viscosity by reducing plasma fibrinogen concentrations and increasing fibrinolytic activity. It is also a non-selective adenosine receptor antagonist. Pentoxifylline administration has been shown to produce dose-related hemorrheologic effects, lowering blood viscosity, and improving erythrocyte flexibility. Pentoxifylline has been shown to increase leukocyte deformability and to inhibit neutrophil adhesion and activation. Tissue oxygen levels have been shown to be significantly increased by therapeutic doses of pentoxifylline in patients with peripheral arterial disease. Clinical trials were conducted using either extended-release pentoxifylline tablets for up to 60 weeks or immediate-release pentoxifylline capsules for up to 24 weeks. Dosage ranges in the tablet studies were 400 mg bid to tid and in the capsule studies, 200-400 mg tid. The incidence of adverse reactions was higher in the capsule studies (where dose related increases were seen in digestive and nervous system side effects) than in the tablet studies. Studies with the capsule include domestic experience, whereas studies with the extended-release tablets were conducted outside the U.S.

Since its discovery as component of the tea leaf by Albert Kossel in 1888, the history of theophylline (CAS 58-55-9) has been a long and successful one. At the turn of the century, theophylline became less expensive due to chemical synthesis and was primarily used as diuretic in subsequent years. It was Samuel Hirsch who discovered the bronchospasmolytic effect of theophylline in 1992, however, despite this pioneering discovery theophylline continued to be used primarily as diuretic and cardiac remedy. The molecular mechanism of bronchodilatation is inhibition of phosphodiesterase(PDE)3 and PDE4, but the anti-inflammatory effect may be due to histone deacetylase (HDAC) activation, resulting in switching off of activated inflammatory genes. Theophylline is indicated for the treatment of acute exacerbations of the symptoms and reversible airflow obstruction associated with asthma and other chronic lung diseases, e.g., emphysema and chronic bronchitis.

Betaine is a methyl derivative of glycine first isolated from the juice of sugar beets. Betaine is found in many common foods, but concentrated significantly in beets, spinach, wheat foods, and shellfish. In addition, betaine can be synthesized within the human body. Betaine participates in the methionine cycle, which produces vital biomolecules including proteins, hormones, phospholipids, polyamines, and nutrients. Betaine is used as a dietary supplement and has a beneficial effect on the human health. In the USA, FDA approved a betaine-containing drug Cystadane for the treatment of homocystinuria. The drug acts as a methyl group donor in the remethylation of homocysteine to methionine.

Caffeine is a methylxanthine alkaloid found in the seeds, nuts, or leaves of a number of plants native to South America and East Asia that is structurally related to adenosine and acts primarily as an adenosine receptor antagonist with psychotropic and anti-inflammatory activities. Upon ingestion, caffeine binds to adenosine receptors in the central nervous system (CNS), which inhibits adenosine binding. This inhibits the adenosine-mediated downregulation of CNS activity; thus, stimulating the activity of the medullary, vagal, vasomotor, and respiratory centers in the brain. The anti-inflammatory effects of caffeine are due the nonselective competitive inhibition of phosphodiesterases. Caffeine is used by mouth or rectally in combination with painkillers (such as aspirin and acetaminophen) and a chemical called ergotamine for treating migraineheadaches. It is also used with painkillers for simple headaches and preventing and treating headaches after epidural anesthesia. Caffeine creams are applied to the skin to reduce redness and itching in dermatitis. Healthcare providers sometimes give caffeine intravenously (by IV) for headache after epidural anesthesia, breathing problems in newborns, and to increase urine flow. In foods, caffeine is used as an ingredient in soft drinks, energy drinks, and other beverages.

Glycine (Cly) is a natural amino acid neurotransmitter that acts as a co-agonist at Glutamate [NMDA] receptors in the brain and is an activator of glycine receptors, GLRA1-3, GLRB. The abnormal Gly levels have been implicated in neuropsychiatric disorders. Alterations in Gly levels are implicated in several diseases of the central nervous system. Glycine was studied in phase II of clinical trials in patients with schizophrenia. The results have shown that using of glycine was associated with reduced symptoms with promising effect sizes and a possibility of improvement in cognitive function. Besides, glycine was also studied in clinical trials phase II in children with cystic fibrosis. The clinical, spirometric and inflammatory status of subjects with cystic fibrosis improved after just 8 weeks of glycine intake, suggesting that this amino acid might constitute a novel therapeutic tool for these patients. In addition, Gly was proposed as a biomarker for brain tumor malignancy. Glycine is a component of a nutrients mixture for peripheral administration to well-nourished mildly catabolic adult patients who require only short-term parenteral nutrition.

Methyl salicylate (or methyl 2-hydroxybenzoate), also known as wintergreen oil, is a natural product and is present in white wine, tea, porcini mushroom Boletus edulis, Bourbon vanilla, clary sage, red sage and fruits including cherry, apple, raspberry, papaya and plum. Methyl salicylate is topically used in combination with methanol and under brand name SALONPAS to temporarily relieves mild to moderate aches and pains of muscles and joints associated with: strains, sprains, simple backache, arthritis, bruises. The precise mechanism of action of methyl salicylate is not known, but there is suggested, that it cause dilation of the capillaries thereby increasing blood flow to the area.

3-Methylxanthine is a metabolite of caffeine and theophylline.