Naphthalene Poisoning – When Mothballs Kill More Than Just Moths (As Seen on House MD)

This is part of our House MD Project series.

In an emotionally charged episode (episode 11 of season 1, called detox), a 16 year old boy named Keith arrives at the hospital after suffering from internal bleeding for a few weeks. Turns out he has hemolytic anemia – a type of anemia in which the blood gets destroyed. Add to that a blood clot in his eye, liver failure and hallucinations and the plot thickens. After a series of misdiagnoses (including lupus) House arrives at the conclusion that the boy has naphthalene poisoning, brought on by termites living in the walls of his bedroom.


Photo by Fox

Danger level: High

What is it?

Naphthalene is a type of chemical, best known as the primary ingredient in mothballs. Exposure to large amounts can damage or destroy red blood cells.

Who gets it?

Naphthalene poisoning occurs mostly in children who suck or chew mothballs. Naphthalene poisoning can also happen by inhalation, since mothballs change slowly into gas form.

Skin exposure to naphthalene has also been shown to cause poisoning – it happened to babies that were dressed in clothes stored with naphthalene mothballs.

About a year ago we covered here a condition called G6PD deficiency. People with this condition are more likely to be poisoned by exposure to naphthalene. 


Mothballs. Photo by Billie Hara

In the House episode, there was a connection between termites and naphthalene. Researchers have found that termites use naphthalene to protect their nests. So, theoretically, exposure to termites may also lead to naphthalene poisoning.

What causes it?

We’ve covered anemia before on A Disease A Day. It’s a condition in which red blood cells – the cells used to transfer oxygen to body organs – are decreased. There are many reasons for that. The reason in naphthalene pois

oning is hemolytic anemia – a condition in which the blood cells get destroyed.

The destruction of blood cells probably causes their precipitation in blood vessels, clogging them, and thus causing blood not to reach its target organs. When an organ doesn’t get enough blood (or, actually, the oxygen the blood delivers) it simply dies, or in medical terms – goes through necrosis.

That’s what happened in the House episode – the boy’s liver started dying.

How does it feel?

The poisoning has symptoms that can occur right after the poisoning and long term effects:

Right after:

  • Hemolytic anemia
  • Damage to the liver or kidney
  • In infants, neurological problems
  • The poisoning is actually “felt” – people complain of headaches, nausea, vomiting, diarrhea, weakness, confusion, anemia, yellowing of the skin, convulsions and even a coma.
  • Cataracts can happen in the eye. A cataract is a condition in which the lens of the eye turns yellow and opaque, limiting our ability to see.

Long term effects:

There are many, and we won’t go into detail here. They contain cataracts, lung inflammation and other effects.

How is it discovered?

The doctor can find out if you are poisoned by naphthalene by listening to your story, seeing your symptoms, and taking a blood test, which will show that you have hemolytic anemia (among other things).

How is it treated?

If you think you have been poisoned, seek medical help immediately. The medical care given in cases of a poisoning include flushing the area thoroughly, giving oxygen if needed (or ventilation if the condition is more serious). If naphthalene was ingested, a gastric lavage (“stomach pumping” or “gastric irrigation”) may be performed, in which the contents of the stomach are cleaned out.

Also milk and fatty meals should be avoided for 2-3 hours to avoid further absorption of the naphthalene.

These are just the preliminary measures. Other treatment measures are beyond the scope of this article.

What happens after treatment?

Supportive treatment is needed in case of a naphthalene poisoning. Otherwise, death can occur.

The bottom line – How do I avoid it?

Not ingesting mothballs and avoiding skin contact is an obvious recommendation.

How do you decrease your chances of inhaling it?

  • You can remove the mothballs and ventilate the house by opening doors and windows.
  • When you remove them use gloves so that you don’t come in contact with the mothballs.
  • If you know you have a real problem and someone in your house has symptoms, you may want to leave the house while it ventilates, and even use a fan to increase air circulation during that time.

In any case, if you have any questions, you should contact your local poison control center (in the US the number is 1-800-222-1222).