What is charcoal?
Charcoal comes from the burning of substances such as oil and wood. It is an absorbent, meaning it can bind up other substances, such as chemicals and gases.
What is it used for?
Charcoal is known to bind certain poisons so it will often be used in acute poisonings. In gastroenterology, it may be helpful in binding methane or sulfide intestinal gases, which are the main offenders in flatus odor. Some researchers think charcoal reduces intestinal gas. Other studies contradict this claim. Still, since charcoal is generally harmless, it can be tried for this purpose. Belching and bloating comes mostly from swallowed air. Charcoal has no effect on these conditions.
How do I take it?
Follow your physician’s instructions carefully. Charcoal is usually taken after meals. Because charcoal can absorb medication while in the digestive tract, take it 2 hours before or 1 hour after any other medication. Store it in a tightly closed container. Keep all medications away from children. Never share your medications with anyone else.
What do I do for a missed dose?
If you miss a dose of this medicine, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and return to your regular schedule. Do not double up on this medication.
Are there interactions with food or beverages?
Do not mix charcoal with milk, ice cream or sherbet since they may decrease the absorptive capacity of the charcoal.
Are there interactions with other drugs?
An interaction generally means that one drug may increase or decrease the effect of another drug. Also, the more medications a person takes, the more likely there will be a drug interaction. Charcoal can absorb other drugs while in the GI tract. Taking it 2 hours before or 1 hour after other medications is recommended.
Do not take charcoal close to the time you take any of the following:
- acetaminophen (Tylenol)
- methotrexate (Rheumatrex)
- barbiturates (phenobarbital)
- phenothiazines (Compazine)
- birth control pills
- propoxyphene (Darvocet)
- anti-convulsants (Tegretol, Dilantin)
- tetracycline (Achromycin)
- digoxin (Lanoxin)
- theophyllines (Theo-Dur)
- furosemide (Lasix)
- tricyclic anti-depressants (Elavil)
Is there a problem if I have another disorder or disease?
At times, a drug may have a different or enhanced effect when other diseases are present. At other times, the drug may worsen or effect another disease. While charcoal may interfere with many drugs, since it is not absorbed, it will not effect any illness or other disorder in the body.
What about allergies?
People who have known allergies or asthma may be at an increased risk for a reaction from any new medication. The physician should always know a patient’s allergy history. Signs of an allergic reaction are skin rash, hives or itching. Of course, a person should not take charcoal if there has been a previous reaction to this or a similar drug.
What if I’m pregnant, considering pregnancy or breast-feeding?
Most females now know that, if possible, no drug, including alcohol, should be taken during pregnancy or lactation. The potential danger, of course, is an injury to the baby. However, some drugs are much safer than others in this regard. So, the FDA has a grading system for each drug which reflects what is known medically. It ranks drugs from A, where medical studies show no evidence for danger to the fetus or mother, to B, C, D and X, where the medical evidence indicates that the risk to the fetus outweighs any benefit to the mother. Charcoal is not ranked but since it is not absorbed from the intestinal tract, it is probably safe to take. However, consult your physician before taking this or any drug during or when planning pregnancy.
What are the effects on sexual function?
There are no known adverse effects of charcoal on sexual function.
Are there other precautions?
If being used for accidental poisoning, do not administer charcoal at the same time as syrup of ipecac. The charcoal will inactivate the ipecac. If diarrhea is a problem and persists for more than 2 days or is accompanied by a fever, consult your physician.
How long is it safe to take charcoal?
Prolonged use does not cause problems so it can be used long-term for months or years.
How about side effects?
Adverse reactions can occur with any drug, even over-the-counter medications. Some of these are mild such as a stomach upset, which may be avoided by taking the medication with food. Minor reactions may go away on their own but if they persist, contact the physician. For major reactions, the patient should contact the physician immediately.
For charcoal, the following are the observed side effects:
- black stools
A physician’s comment…
Charcoal in small or moderate amounts is safe and can be tried in cases of bloating and flatus. However, its only known action is to actively bind up certain chemicals and gases. The likely effect will be to reduce the offensive odor of rectal gas. Do not expect it to reduce the amount of rectal gas.