Hi Dona,
Using the word "spread" is tough. The rash never spreads in a strict sense. So let's talk about ways you can get the rash on other parts of the body (or see a rash get bigger after days).
Scratching can cause rashes. It's a nasty itch-scratch cycle. Scratching causes histamines to be released to the skin which causes a rash which causes more itching and the cycle is repeated.
Thickness of the skin - it can take time for a rash to occur on various places depending on the amount of oil and thickness of the skin. This is why most folks will never have a poison ivy rash on their palms or bottoms of the feet - skin is too thick.
Recontamination - coming into contact with urushiol oil days later. The oil is quite stable and can last for months or years. Proper cleanup is essential to prevent recontamination. One area often overlooked is under the fingernails. You've got to clean everywhere.
Pets - look what the cat drug in! Urushiol oil can stay on objects for days, months, years so you can easily come in contact with the oil via the fur on your pet, garden tools, clothes, etc.
That covers the bulk of it. It isn't that unusual for rashes to popup over a period of time. |
