Caffine Intoxication and Dependency
Abstract
Caffeine, one of the world's most popular psychoactive substances, is sought for its central nervous system stimulant effects. If coffee, tea, and soda alone do not provide the desired stimulation, some consumers are turning to the newest fad in the caffeine market, energy drinks. These beverages are loaded with caffeine and sugar, infused with herbal additives, and marketed particularly to youth. Caffeine produces dose-dependent symptoms, and intoxication may develop with overconsumption. Caffeine is also recognized for its addictive properties, and discontinuation results in a withdrawal syndrome. Nurse practitioners are encouraged to consider caffeine intoxication, addiction, and withdrawal syndrome in the differential when patients complain of characteristic symptoms. Ongoing nutritional assessment and education on moderation are key to reducing the overuse of caffeinated energy drinks.
Introduction
If you have relied on an afternoon double-shot caramel macchiato or a 64-ounce Mountain Dew guzzler to get you through the day, you are not alone. People have been getting their caffeine buzz for decades. Liquid Cocaine, Rock Star, and Red Bull are examples of the newest trend for those not satisfied with soda and coffee alone. Containing caffeine levels significantly higher than the current Food and Drug Administration (FDA) caffeine restriction, these popular beverages effectively bypass the FDA caffeine restriction of 72 mg per 12 fluid ounces by virtue of the argument that they fall within the 1994 Dietary Supplement Health and Education Act (Figure 1).[1] Most contain the added ingredients high fructose corn syrup, sucrose, and herbal additives such as taurine, L-carnitine, ginseng, and milk thistle, offering the illusion of a healthy alternative for a quick-energy high.
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Figure 1. |
Energy drinks pose a unique challenge to health care providers and the community at large. More than 500 new energy drinks have been launched this year and this 3.4 billion dollar a year industry continues to grow.[2] Advertisements appeal to youth and are made attractive by claims of increased performance, attention, endurance, and weight loss. Products are printed with the logos, "zero crash," "sustained energy," and "party like a rock star." Manufacturers of the energy drink Cocaine went so far as to print the word cocaine on the can in such a manner that it resembles a line of illicit powdered cocaine.
Presentation
Caffeine intoxication may manifest itself in many ways and is often difficult to distinguish in the presence of a vague patient history or chief complaint. Virtually every organ system is affected when caffeine is taken in excess Table 1). Patients with caffeine intoxication often present with nausea and emesis that can be difficult to control. Additionally, less severe characteristic symptoms of high consumption of caffeine originate from the stimulatory and psychoactive properties of the drug. Patients may complain of agitation, nervousness, headache, tremor, and sleep disturbances. More life-threatening manifestations that require additional testing and treatment include tachydysrhythmias and electrolyte disturbances, including hypokalemia, hypomagnesemia, and hypophosphatemia. Hyperglycemia, metabolic acidosis with increased serum lactate, and seizures may also occur.[4] The clinical presentation typically resolves between 4 to 6 hours after consumption.
Assessment
Laboratory assessment of caffeine blood levels cannot be easily obtained, but are not necessary for the management of clinical symptoms. A urine drug screen and thyroid studies are beneficial when exploring the differentials of substances of abuse or hyperthyroidism. An electrolyte panel is necessary for the careful assessment and correction of hypokalemia and hypomagnesemia. This is particularly important in the presence of ventricular dysrhythmia.
Management of Intoxication
Clinical management of caffeine intoxication is directed at controlling symptom presentation. An antacid of the provider's preference may improve symptoms related to gastritis. Emesis may safely be controlled with utilization of metoclopramide or ondansetron. Phenothiazine antiemetics are contraindicated because they can lower the seizure threshold, placing the patient at greater risk for seizure activity. Administration of oral diazepam or lorazepam is appropriate for symptomatic relief of agitation and anxiety. Diazepam IV 5 to 10 mg or lorazepam IV 2 to 4 mg are preferred starting doses for the treatment of seizure activity, realizing repeated doses may be necessary.[4] Sinus tachycardia is common, but typically does not require intervention. A dysrhythmia that threatens hemodynamic stability should be treated using standard advanced cardiac life support and pediatric advanced life support protocols.[4]
Caffeinism and Dependence
Caffeine meets all the requirements for being an addictive substance, including dependence, tolerance, and withdrawal. Caffeinism is a syndrome resulting from the chronic consumption of caffeine and addiction. The symptoms include nervous irritability, tremulousness, occasional muscle twitching, sensory disturbances, tachypnea, palpitation, flushing, arhythmias, diuresis, and gastrointestinal disturbances. Patients may present with generalized anxiety or depression. Because many do not view caffeine as addictive, patients may not think to provide a careful caffeine history. If not prompted by the nurse practitioner (NP), the potential for misdiagnosis exists. Withdrawal of caffeine may be an onerous task. Following an orderly progression, headache is often the most common initial complaint. This becomes evident within the first 12 to 24 hours after termination of caffeine. Additional symptoms include irritability, fatigue, dysphoric mood, difficulty concentrating/decreased cognitive performance, depression, and muscle aches and stiffness. Peak withdrawal effects are anticipated to occur 20 to 48 hours after removal of caffeine. The total duration of the withdrawal syndrome ranges between 2 days to 1 week.[14] Withdrawal is not limited to adults. Adolescents and children have also been reported to suffer from withdrawal effects. The incidence of caffeine addiction and withdrawal may increase as energy drinks are increasingly targeted to this population.
Caffeine should be removed from the diet gradually. Tapering a patient's daily consumption over a period of time may decrease the likelihood of withdrawal symptoms or reduce their severity. One strategy may be to begin mixing 1/2 energy drink with 1/2 non-caffeinated beverage, the ultimate goal being to move the patient toward replacing high caffeine energy drinks with healthier options such as water, whole fruit juices, or caffeine-free beverages. Referral to a dietician may provide that extra support for those in need of additional guidance.
Caffeine and Chronic Medical Conditions
Caffeine consumption elicits a prolonged stress response in the body by competitively antagonizing adenosine receptors, inhibiting phosphodiesterase, and increasing circulating catecholamines and intracellular cAMP. There is a corresponding increase in blood pressure and heart rate, release of blood glucose by the liver, an increase in gastric acid secretion, a decrease in lower esophageal sphincter tone, and an increased colonic contractile activity. These clinical effects make caffeine intake of particular importance for NPs providing care for the patient with hypertension, diabetes mellitus, gastroesophageal reflux disease, or irritable bowel syndrome. Medical management and disease control may be more difficult to achieve.
Education and Implications for the Nurse Practitioner
The landscape of commercially marketed energy beverages may change. The physiological effects of caffeine will remain constant. Patient education plays a key role in clinical practice. Promoting moderation, counseling on the acute adverse affects, as well as imparting an understanding of the addictive properties of caffeine is essential. A nutritional assessment, even if done in a brief format, may help the clinician glean an understanding of a patient's daily beverage consumption. Asking what and how much of a product is consumed per day provides a foundation to begin the education on caffeine. It is particularly important to begin this process with young children in the hopes it will be reinforced throughout their lifespan. Instruct patients and families to read labels and be familiar with other names caffeine may take (ie, guarana, cola nut). Those with chronic disease states such as diabetes mellitis, hypertension, irritable bowel syndrome or gastroesophageal reflux disease should be informed of the implications caffeine can have on the management of their disease state. Finally, if a patient presents with characteristic withdrawal symptoms, provide supportive reassurance, and symptom-based treatment. Advise the patient on the expected clinical signs and the course of the withdrawal syndrome. For those patients actively being treated for withdrawal symptoms recommend they return to the clinic for evaluation if symptoms persist for more than 2 weeks. Persistent symptoms may suggest an alternate diagnosis.