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CAFFEINE

Other Names:

1,3,7-Trimethyl-1H-purine- 2,6(3H,7H)-dione, 1,3,7-trimethylxanthine, 1,3,7-triméthylxanthine, Anhydrous Caffeine, Cafeina, Caféine, Caféine Anhydre, Caféine Benzodate de Sodium, Caffeine Sodium Benzoate, Caffeine Anhydrous, Caffeine Citrate, Ca...
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Anhydrous Caffeine (CAFFEINE) Overview
Anhydrous Caffeine (CAFFEINE) Uses
Anhydrous Caffeine (CAFFEINE) Side Effects
Anhydrous Caffeine (CAFFEINE) Interactions
Anhydrous Caffeine (CAFFEINE) Dosing
Anhydrous Caffeine (CAFFEINE) Overview Information

Caffeine is a chemical found in coffee, tea, cola, guarana, mate, and other products.

Caffeine is most commonly used to improve mental alertness, but it has many other uses. 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.

Some people use caffeine for asthma, gallbladder disease, attention deficit-hyperactivity disorder (ADHD), shortness of breath in newborns, and low blood pressure. Caffeine is also used for weight loss and type 2 diabetes. Very high doses are used, often in combination with ephedrine, as an alternative to illegal stimulants.

Caffeine is one of the most commonly used stimulants among athletes. Taking caffeine, within limits, is allowed by the National Collegiate Athletic Association (NCAA). Urine concentrations over 15 mcg/mL are prohibited. It takes most people about 8 cups of coffee providing 100 mg/cup to reach this urine concentration.

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.

People with voice disorders, singers, and other voice professionals are often advised against using caffeine. However, until recently, this recommendation was based only on hearsay. Now developing research seems to indicate that caffeine may actually harm voice quality. But further study is necessary to confirm these early findings.

How does it work?

Caffeine works by stimulating the central nervous system (CNS), heart, muscles, and the centers that control blood pressure. Caffeine can raise blood pressure, but might not have this effect in people who use it all the time. Caffeine can also act like a “water pill” that increases urine flow. But again, it may not have this effect in people who use caffeine regularly. Also, drinking caffeine during moderate exercise is not likely to cause dehydration.

Anhydrous Caffeine (CAFFEINE) Uses & Effectiveness What is this?

Effective for:

  • Headache, including migraine and headache following surgery. Caffeine is an FDA-approved product for use with painkilling medications for improving pain relief.

Likely Effective for:

  • Mental alertness. Drinking caffeinated beverages throughout the day keeps the mind alert according to most research. Combining caffeine with glucose as an “energy drink” seems to improve mental performance better than either caffeine or glucose alone.

Possibly Effective for:

  • Improving athletic performance. Taking caffeine seems to increase physical endurance and might delay exhaustion. It might also reduce feelings of exertion while exercising for long periods. But caffeine doesn't seem to help with short-term, high-intensity exercise such as sprinting and lifting.
  • Preventing dizziness on standing up (orthostatic hypotension) in older people. Dizziness on standing is sometimes a result of low blood pressure. Drinking caffeinated beverages seems to increase blood pressure in older people with low blood pressure.
  • Preventing Parkinson’s disease. There is some evidence that suggests people who drink caffeinated beverages such as coffee, tea, and cola have a decreased risk of Parkinson’s disease.
  • Asthma. Caffeine appears to improve airway function somewhat in people with asthma for up to four hours.
  • Preventing type 2 diabetes, when caffeine is acquired from drinking coffee or tea. Drinking coffee or tea is associated with a lower risk of developing type 2 diabetes. It appears that the more the caffeine, the lower the risk. In North American men, consuming 417 mg of caffeine per day from coffee or tea is associated with 20% lower risk of developing type 2 diabetes compared to men who consume less than 37 mg per day. North American women consuming 258 mg to 530 mg of caffeine per day from coffee or tea seem to have 10% to 30% lower risk of developing type 2 diabetes compared to women consuming less than 140 mg per day. Similarly, Japanese adults who consume 416 mg or more of caffeine per day from beverages including coffee or green tea seem to have a 33% lower risk of developing type 2 diabetes compared to those who consume 57 mg/day or less.
  • Breathing problems in infants. Caffeine given by mouth or intravenously (by IV) appears to improve breathing in infants born too early. It seems to reduce the number of episodes of shortness of breath by at least 50% over 7-10 days of treatment.
  • Preventing gallstones. Drinking caffeinated beverages that provide 400 mg or more of caffeine per day seems to significantly reduce the risk of developing gallstone disease. The effect seems to be dose-dependent. Taking 800 mg caffeine per day seems to work best.
  • Weight loss, when given with other drugs. Taking caffeine in combination with ephedrine seems to help reduce weight short-term. Taking 192 mg of caffeine in combination with 90 mg of ephedra per day for 6 months seems to cause a modest weight reduction (5.3 kg or 11.66 pounds) in overweight people (people with a body mass index (BMI) between 25-40). This combination, along with limiting fat intake to 30 percent of calories and moderate exercise, also seems to reduce body fat, decrease “bad” low-density lipoprotein (LDL) cholesterol, and increase “good” high-density lipoprotein (HDL) cholesterol. But there can be unwanted side effects. Even in carefully screened and monitored otherwise healthy adults, caffeine/ephedra combinations can cause changes in blood pressure and heart rate.
  • Headache after epidural anesthesia.

Possibly Ineffective for:

  • Treating attention deficit-hyperactivity disorder (ADHD) in children.

Insufficient Evidence for:

  • Skin irritation, redness, and itching.
  • Improving exercise endurance.
  • Overdose.
  • Other conditions.
More evidence is needed to rate caffeine for these uses.


Anhydrous Caffeine (CAFFEINE) Side Effects & Safety

Caffeine is LIKELY SAFE for most adults when used appropriately. Caffeine can cause insomnia, nervousness and restlessness, stomach irritation, nausea and vomiting, increased heart rate and respiration, and other side effects. Caffeine can make sleep disorders in patients with acquired immunodeficiency syndrome (AIDS) worse. Larger doses might cause headache, anxiety, agitation, chest pain, and ringing in the ears.

Large doses may be UNSAFE and can cause irregular heartbeats and even death.

Special Precautions & Warnings:

Pregnancy and breast-feeding: Caffeine is POSSIBLY SAFE in pregnant or breast-feeding women in daily amounts of less than 200 mg. This is about the amount in 1-2 cups of coffee. Consuming larger amounts during pregnancy might increase the chance of miscarriage and other problems. Caffeine passes into breast milk, so nursing mothers should closely monitor caffeine intake to make sure it is on the low side. Caffeine in large amounts is POSSIBLY UNSAFE during breast-feeding. Caffeine can cause sleep disturbances, irritability, and increased bowel activity in breast-fed infants.

Anxiety disorders: Caffeine might make these conditions worse. Use with care.

Bipolar disorder: Too much caffeine might make this condition worse. In one case, a 36-year-old man with controlled bipolar disorder was hospitalized with symptoms of mania after drinking several cans of an energy drink containing caffeine, taurine, inositol, and other ingredients (Red Bull Energy Drink) over a period of 4 days. Use caffeine with care and in low amounts if you have bipolar disorder.

Bleeding disorders: There is concern that caffeine might aggravate bleeding disorders. Use caffeine with care if you have a bleeding disorder.

Heart conditions: Caffeine can cause irregular heartbeat in sensitive people. Use caffeine with caution.

Diabetes: Some research suggests that caffeine may affect the way the body uses sugar and might worsen diabetes. But the effect of caffeinated beverages and herbs has not been studied. If you have diabetes, use caffeine with caution.

Diarrhea: Caffeine, especially when taken in large amounts, can worsen diarrhea.

Irritable bowel syndrome (IBS): Caffeine, especially when taken in large amounts, can worsen diarrhea and might worsen symptoms of IBS.

Glaucoma: Caffeine increases the pressure inside the eye. The increase occurs within 30 minutes and lasts for at least 90 minutes after drinking caffeinated beverages.

High blood pressure: Consuming caffeine might increase blood pressure in people with high blood pressure. However, this effect might be less in people who use caffeine regularly.

Weak bones (osteoporosis): Caffeine can increase the amount of calcium that is flushed out in the urine. If you have osteoporosis or low bone density, caffeine should be limited to less than 300 mg per day (approximately 2-3 cups of coffee). It’s also a good idea to get extra calcium to make up for the amount that may be lost in the urine. Older women with an inherited disorder that affects the way vitamin D is used should use caffeine with caution. Vitamin D works with calcium to build bones.

Anhydrous Caffeine (CAFFEINE) Interactions What is this?

Major Interaction Do not take this combination

  • Ephedrine interacts with CAFFEINE

    Stimulant drugs speed up the nervous system. Caffeine and ephedrine are both stimulant drugs. Taking caffeine along with ephedrine might cause too much stimulation and sometimes serious side effects and heart problems. Do not take caffeine-containing products and ephedrine at the same time.


Moderate Interaction Be cautious with this combination

  • Adenosine (Adenocard) interacts with CAFFEINE

    Caffeine might block the effects of adenosine (Adenocard). Adenosine (Adenocard) is often used by doctors to do a test on the heart. This test is called a cardiac stress test. Stop consuming caffeine-containing products at least 24 hours before a cardiac stress test.

  • Antibiotics (Quinolone antibiotics) interacts with CAFFEINE

    The body breaks down caffeine to get rid of it. Some antibiotics might decrease how quickly the body breaks down caffeine. Taking these antibiotics along with caffeine can increase the risk of side effects including jitteriness, headache, increased heart rate, and other side effects.

    Some antibiotics that decrease how quickly the body breaks down caffeine include ciprofloxacin (Cipro), enoxacin (Penetrex), norfloxacin (Chibroxin, Noroxin), sparfloxacin (Zagam), trovafloxacin (Trovan), and grepafloxacin (Raxar).

  • Cimetidine (Tagamet) interacts with CAFFEINE

    The body breaks down caffeine to get rid of it. Cimetidine (Tagamet) can decrease how quickly your body breaks down caffeine. Taking cimetidine (Tagamet) along with caffeine might increase the chance of caffeine side effects including jitteriness, headache, fast heartbeat, and others.

  • Clozapine (Clozaril) interacts with CAFFEINE

    The body breaks down clozapine (Clozaril) to get rid of it. Caffeine seems to decrease how quickly the body breaks down clozapine (Clozaril). Taking caffeine along with clozapine (Clozaril) can increase the effects and side effects of clozapine (Clozaril).

  • Dipyridamole (Persantine) interacts with CAFFEINE

    Caffeine might block the affects of dipyridamole (Persantine). Dipyridamole (Persantine) is often used by doctors to do a test on the heart. This test is called a cardiac stress test. Stop consuming caffeine-containing products at least 24 hours before a cardiac stress test.

  • Disulfiram (Antabuse) interacts with CAFFEINE

    The body breaks down caffeine to get rid of it. Disulfiram (Antabuse) can decrease how quickly the body gets rid of caffeine. Taking caffeine along with disulfiram (Antabuse) might increase the effects and side effects of caffeine including jitteriness, hyperactivity, irritability, and others.

  • Estrogens interacts with CAFFEINE

    The body breaks down caffeine to get rid of it. Estrogens can decrease how quickly the body breaks down caffeine. Taking caffeine along with estrogens might cause jitteriness, headache, fast heartbeat, and other side effects. If you take estrogens limit your caffeine intake.

    Some estrogen pills include conjugated equine estrogens (Premarin), ethinyl estradiol, estradiol, and others.

  • Fluvoxamine (Luvox) interacts with CAFFEINE

    The body breaks down caffeine to get rid of it. Fluvoxamine (Luvox) can decrease how quickly the body breaks down caffeine. Taking caffeine along with fluvoxamine (Luvox) might cause too much caffeine in the body, and increase the effects and side effects of caffeine.

  • Lithium interacts with CAFFEINE

    You body naturally gets rid of lithium. Caffeine can increase how quickly your body gets rid of lithium. If you take products that contain caffeine and you take lithium, stop taking caffeine products slowly. Stopping caffeine too quickly can increase the side effects of lithium.

  • Medications for depression (MAOIs) interacts with CAFFEINE

    Caffeine can stimulate the body. Some medications used for depression can also stimulate the body. Taking caffeine along with some medications for depression might cause serious side effects including fast heartbeat, high blood pressure, nervousness, and others.

    Some of these medications used for depression include phenelzine (Nardil), tranylcypromine (Parnate), and others.

  • Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs) interacts with CAFFEINE

    Caffeine might slow blood clotting. Taking caffeine along with medications that also slow clotting might increase the chances of bruising and bleeding.

    Some medications that slow blood clotting include aspirin, clopidogrel (Plavix), diclofenac (Voltaren, Cataflam, others), ibuprofen (Advil, Motrin, others), naproxen (Anaprox, Naprosyn, others), dalteparin (Fragmin), enoxaparin (Lovenox), heparin, warfarin (Coumadin), and others.

  • Pentobarbital (Nembutal) interacts with CAFFEINE

    The stimulant effects of caffeine can block the sleep-producing effects of pentobarbital.

  • Phenylpropanolamine interacts with CAFFEINE

    Caffeine can stimulate the body. Phenylpropanolamine can also stimulate the body. Taking caffeine along with phenylpropanolamine might cause too much stimulation and increase heartbeat, blood pressure, and cause nervousness.

  • Riluzole (Rilutek) interacts with CAFFEINE

    The body breaks down riluzole (Rilutek) to get rid of it. Taking caffeine along with riluzole (Rilutek) might decrease how fast the body breaks down riluzole (Rilutek) and increase the effects and side effects of riluzole (Rilutek).

  • Stimulant drugs interacts with CAFFEINE

    Stimulant drugs speed up the nervous system. By speeding up the nervous system, stimulant medications can make you feel jittery and speed up your heart rate. Caffeine might also speed up the nervous system. Taking caffeine along with stimulant drugs might cause serious problems including increased heart rate and high blood pressure. Avoid taking stimulant drugs along with caffeine.

    Some stimulant drugs include diethylpropion (Tenuate), epinephrine, phentermine (Ionamin), pseudoephedrine (Sudafed), and many others.

  • Theophylline interacts with CAFFEINE

    Caffeine works similarly to theophylline. Caffeine can also decrease how quickly the body gets rid of theophylline. Taking theophylline along with caffeine might increase the effects and side effects of theophylline.

  • Verapamil (Calan, Covera, Isoptin, Verelan) interacts with CAFFEINE

    The body breaks down caffeine to get rid of it. Verapamil (Calan, Covera, Isoptin, Verelan) can decrease how quickly the body gets rid of caffeine. Taking caffeine along with verapamil (Calan, Covera, Isoptin, Verelan) can increase the risk of side effects for caffeine including jitteriness, headache, and an increased heartbeat.


Minor Interaction Be watchful with this combination

  • Alcohol interacts with CAFFEINE

    The body breaks down caffeine to get rid of it. Alcohol can decrease how quickly the body breaks down caffeine. Taking caffeine along with alcohol might cause too much caffeine in the bloodstream and caffeine side effects including jitteriness, headache, and fast heartbeat.

  • Birth control pills (Contraceptive drugs) interacts with CAFFEINE

    The body breaks down caffeine to get rid of it. Birth control pills can decrease how quickly the body breaks down caffeine. Taking caffeine along with birth control pills can cause jitteriness, headache, fast heartbeat, and other side effects.

    Some birth control pills include ethinyl estradiol and levonorgestrel (Triphasil), ethinyl estradiol and norethindrone (Ortho-Novum 1/35, Ortho-Novum 7/7/7), and others.

  • Fluconazole (Diflucan) interacts with CAFFEINE

    The body breaks down caffeine to get rid of it. Fluconazole (Diflucan) might decrease how quickly the body gets rid of caffeine. Taking caffeine along with fluconazole (Diflucan) might cause caffeine to stay in to body too long and increase the risk of side effects such as nervousness, anxiety, and insomnia.

  • Medications for diabetes (Antidiabetes drugs) interacts with CAFFEINE

    Caffeine might increase blood sugar. Diabetes medications are used to lower blood sugar. Taking some medications for diabetes along with caffeine might decrease the effectiveness of diabetes medications. Monitor your blood sugar closely. The dose of your diabetes medication might need to be changed.

    Some medications used for diabetes include glimepiride (Amaryl), glyburide (DiaBeta, Glynase PresTab, Micronase), insulin, pioglitazone (Actos), rosiglitazone (Avandia), chlorpropamide (Diabinese), glipizide (Glucotrol), tolbutamide (Orinase), and others.

  • Mexiletine (Mexitil) interacts with CAFFEINE

    The body breaks down caffeine to get rid of it. Mexiletine (Mexitil) can decrease how quickly the body breaks down caffeine. Taking Mexiletine (Mexitil) along with caffeine might increase the effects and side effects of caffeine.

  • Terbinafine (Lamisil) interacts with CAFFEINE

    The body breaks down caffeine to get rid of it. Terbinafine (Lamisil) can decrease how fast the body gets rid of caffeine. Taking caffeine along with terbinafine (Lamisil) can increase the risk of caffeine side effects including jitteriness, headache, increased heartbeat, and other effects.


Anhydrous Caffeine (CAFFEINE) Dosing

The following doses have been studied in scientific research:

BY MOUTH:

  • For headache or improving mental alertness: 250 mg per day.
  • For tiredness: 150-600 mg.
  • For improving athletic performance: 2-10 mg/kg or more has been used. However, doses in excess of 800 mg per day can result in urine levels greater than the 15 mcg/mL allowed by the National Collegiate Athletic Association.
  • For weight loss: the ephedrine/caffeine combination products are commonly dosed 20 mg/200 mg three times per day.
  • For headache after epidural anesthesia: 300 mg.
  • For preventing gallstone disease: intake of 400 mg or more of caffeine per day.
  • For preventing Parkinson’s disease: men drinking 421-2716 mg of total caffeine daily have the lowest risk of developing Parkinson's disease, when compared to other men. However, men who drink as little as 124-208 mg of caffeine daily also have a significantly lower chance of developing Parkinson's disease. In women, moderate caffeine intake per day (1-3 cups of coffee per day) seems to be best.
One cup of brewed coffee provides from 95-200 mg of caffeine. An 8-ounce serving of black tea provides from 40-120 mg of caffeine. An 8-ounce serving of green tea provides 15-60 mg of caffeine. Soft drinks such as cola provide from 20-80 mg of caffeine per 12 ounce serving. Sports or energy drinks typically provide from 48-300 mg of caffeine per serving.

INTRAVENOUS:
  • Caffeine is given intravenously (by IV) by healthcare providers for breathing problems in infants and for headache after epidural anesthesia.

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Conditions of Use and Important Information: This information is meant to supplement, not replace advice from your doctor or healthcare provider and is not meant to cover all possible uses, precautions, interactions or adverse effects. This information may not fit your specific health circumstances. Never delay or disregard seeking professional medical advice from your doctor or other qualified health care provider because of something you have read on WebMD. You should always speak with your doctor or health care professional before you start, stop, or change any prescribed part of your health care plan or treatment and to determine what course of therapy is right for you.

This copyrighted material is provided by Natural Medicines Comprehensive Database Consumer Version. Information from this source is evidence-based and objective, and without commercial influence. For professional medical information on natural medicines, see Natural Medicines Comprehensive Database Professional Version. © Therapeutic Research Faculty 2009.

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