Pseudoephedrine Caffeine

Classes of substances currently banned by the IOC include stimulants (amphetamines, cocaine, caffeine, pseudoephedrine), narcotics (heroin, methadone), anabolic agents (testosterone, nandrolone), diuretics (acetazolamide, spironolactone), and peptide hormones and their mimetics and analogs (erythropoietin, human growth hormone). Alcohol and marijuana at specified levels are also prohibited. For the latter, a level of as little as 15 ng/mL of 11-nor-A°-tetrahydrocannabinol-9-carboxylic acid is a violation of the rules. A complete... 

At one time, Coca-Cola actually contained a form of cocaine. These days, the primary stimulant in Coca-Cola and many other beverages is caffeine. Other stimulants are less obvious. Chocolate contains theobromine, a caffeinelike stimulant. Nondrowsy cold remedies contain pseudoephedrine, a relative of ephedra, another plant-alkaloid stimulant. 

Stimulant drugs commonly abused in the USA include methamphetamine ("crank," "crystal"), methylenedioxymethamphetamine (MDMA, "ecstasy"), and cocaine ("crack") as well as pharmaceuticals such as pseudoephedrine (Sudafed) and ephedrine (as such and in the herbal agent Ma-huang) (see Chapter 32). Caffeine is often added to dietary supplements sold as "metabolic enhancers" or "fat-burners" and is also sometimes combined with pseudoephedrine in underground pills sold as amphetamine substitutes. 

The main classes of over-the-counter stimulants contain caffeine, ephedrine/pseudoephedrine, or herbal varieties of stimulants. Each of these will be discussed in this chapter. 

For most substances, just their presence in a urine sample means a positive result. Other substances must be present in an amount higher than a certain threshold. According to Dr. Ayotte, a male athlete would have to consume "10 very strong French coffees within 15 min" to go over the 12 mg/L limit for caffeine. Ephedrines and pseudoephedrines, two decongestants that are found in cough remedies and that act as stimulants, have a cut-off level. This allows athletes to take them up to one or two days before a competition. 

ASA = aspirin NSAIDs = non-steroidal anti-inflammatory drugs, such as ibuprofen, naproxen, and diclofenac CNS stimulants include drugs such as pseudoephedrine, dextroamphetamine, theophylline, and caffeine MAO = monoamine oxidase CNS depressants include drugs such as benzodiazepines, barbiturates, and ethanol SSRIs = selective serotonin reuptake inhibitors, such as fluoxetine, sertraline, and paroxetine. Antidiabetic agents include drugs such as insulin, glipizide, glyburide, and metformin. 

Ephedrine and pseudoephedrine have been measured in guinea pig plasma using HPLC with fluorescence detection, following precolumn derivatization with 5-dimethylamino-napthalene-1-sulfonyl chloride in acetonitrile. The mobile phase was 0.6% phosphate buffer (pH 6.5)-methanol (3 8 v/v). Jacob et al. developed an LC-atmospheric pressure chemical ionization MS-MS method for the quantitaion of various alkaloids found in ephedra-containing dietary supplements and also in plasma and urine from subjects using these supplements. Using this method, the concentrations of ephedrine, pseudoephedrine, norephedrine, norpseudoephedrine, methylephedrine, methylpseudoephedrine and caffeine were determined in low nanogram quantities in plasma and urine. The analytical cycle time for this method was 12 min. 

Antidepressants selective serotonin reuptake inhibitors, tricyclic antidepressants Antihypertensives felodipine Antibiotics quinolones, isoniazid Bronchodilators albuterol, theophylline Corticosteroids prednisone Dopa agonists levodopa Herbals ma huang, ginseng, ephedra Nonsteroidal anti-inflammatory drugs ibuprofen Stimulants amphetamines, methylphenidate, caffeine, cocaine Sympathomimetics pseudoephedrine Thyroid hormones levothyroxine Toxicity anticholinergics, antihistamines, digoxin Withdrawal alcohol, sedatives... 

Phenylpropanolamine also increases caffeine plasma levels. Whether there is also an effect on theophylline distribution kinetics is a matter of some debate (Lake et al., 1990 Upton, 1991). Even if such an effect does exist, however, it is not known whether such an effect would be of any clinical significance in the case of ma huang, which contains only very small amounts of pure phenylpropanolamine. Reduced metabolism of pseudoephedrine is... 

A. To control excessive sinus tachycardia or ventricular arrhythmias caused by catecholamine excess (eg, theophylline or caffeine), sympathomimetic drug intoxication (eg, amphetamines, pseudoephedrine, or cocaine), or excessive myocardial sensitivity (eg, chloral hydrate, freons, or chlorinated and other hydrocarbons). 

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