Caffeine and nicotine are the most popular stimulants used today, with roughly 400 million cups of coffee consumed daily and 36.5 million current cigarette smokers, according to a 2015 study conducted by the Centers for Disease Control and Prevention. Nicotine, however, is treated separately psychiatrically under tobacco use disorder. Conversely, caffeine misuse does not qualify as an addictive disorder; thus it can not be diagnosed as a stimulant use disorder or any other substance use disorder. Certain isolated conditions related to caffeine are recognized in the DSM-5’s "substance-related" section, however: caffeine intoxication, caffeine withdrawal and other caffeine-induced disorders (e.g., Anxiety and Sleep Disorders). Signs and symptoms
Short-term effects
Even in small doses, stimulants cause a decrease in appetite, an increase in physical activity and alertness, convulsions, an elevated body temperature, increased respiration, irregular heartbeat, and increased blood pressure; some of which can cause sudden death depending upon the medical history of the user, even among first-time users. Long-term effects
The long-term use of stimulants can ultimately cause very serious medical issues, including addiction. Stimulant addiction, similar to other kinds of addiction, involves neurobiological changes that cause sensitization of the reward system to the stimulus in question (stimulants, in this case). People who use stimulants for a prolonged period frequently experience physiological changes that can be detrimental to their quality of life and require long-term treatment.
Thus, evidence is still rare whether these two disorders are separate entities, or rather clusters on a phenotypic continuum of PRPS1-related disease. Diagnosis
Arts syndrome should be included in the differential diagnosis of infantile hypotonia and weakness aggravated by recurrent infection with a family history of X-linked inheritance. Sequence analysis of PRPS1, the only gene associated with Arts syndrome, has detected mutations in both kindreds reported to date. Arts syndrome patients were also found to have reduced levels of hypoxanthine levels in urine and uric acid levels in the serum. In vitro, PRS-1 activity was reduced in erythrocytes and fibroblasts. Treatment
Currently, purine replacement via S-adenosylmethionine (SAM) supplementation in people with Arts syndrome appears to improve their condition. This suggests that SAM supplementation can alleviate symptoms of PRPS1 deficient patients by replacing purine nucleotides  and open new avenues of therapeutic intervention. Other non-clinical treatment options include educational programs tailored to their individual needs. Sensorineural hearing loss has been treated with cochlear implantation with good results. Ataxia and visual impairment from optic atrophy are treated in a routine manner. Routine immunizations against common childhood infections and annual influenza immunization can also help prevent any secondary infections from occurring.Regular neuropsychological, audiologic, and ophthalmologic examinations are also recommended. Carrier testing for at-risk relatives and prenatal testing for pregnancies at increased risk are possible if the disease-causing mutation in the family is known. References


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