Poison Oak Rash Progression: Case Study


In my previous posting I described a close encounter with poison oak and the decontamination and cleanup efforts I felt were appropriate afterward.  In this posting I will focus on my experience with the rash as it has progressed to date, Day 19.  I’m past the worst, thankfully, but still have more recovery to look forward to.  Why document my experience this way?  Partly because I’m an observational scientist by training, and partly out of an odd (horrified?) fascination with what was happening to my body.

With regard to my encounter: While I was trying to bushwhack around the down tree I surmise that I more or less straddled some poison oak brush, and almost certainly I stepped into a section that basically lifted up the cuff of my hiking pants and gave my right shin a good swipe.  By far the worst area is on my right shin, with various spots scattered up and down the insides of my legs between my socks and underwear, plus somewhat diffuse areas behind both knees, more on the right than on the left.

In my previous post I mentioned one good practice that I do: change from hiking boots to regular shoes as soon as I return to my car.  Another good practice is that I remove my hiking gloves immediately.  By doing that I probably avoided some cross-contamination, particularly around my face.  I honestly don’t remember to what extent I touched the brush with my hands during my off-trail episode.  In any case I only got one small bump on my neck, and a few on each wrist between my shirt cuff and gloves.  The vast majority of the rash was on my legs and probably got there by urushiol leaking through my hiking pants.  This explanation of how I touched poison oak is basically an amateur forensic description based on the location of my rash, including where it did and did not appear.

The first sign of rash was on Day 4.  It was an area less than 1 inch in diameter on my right shin, just vaguely itchy.  The next morning I realized I might have encountered poison oak on my hike and started to read up on symptoms, treatment, and cleanup.  I learned that a delayed response – and 96 hours is considered “delayed” – is not uncommon for a first reaction.  The rash developed over the next several days, with more bumps appearing every day, mostly on my legs.  A delayed bump often indicates an initial lesser level of urushiol exposure rather than a subsequent cross-contamination.

By Day 7 I had emerged from denial and accepted that I was most likely dealing with a poison oak rash, but it is pertinent to mention that I had almost no itching yet.  I was using aloe vera to soothe all of the rash areas.  Besides reading up on-line, I talked to an advice nurse to make sure I understood appropriate home treatment.  After that conversation I started taking antihistamines to reduce itching, using caladryl lotion to dry the weeping (replacing aloe vera), and cool water compresses for comfort.   Around Day 9 I noticed a row of bumps running up my left leg just above the ankle: about 5 bumps along a 2” length.  On Day 10 I was starting to have noticeable itching.  The initial rash on my right leg was getting bigger and redder: the picture in the header box for this post shows this area on Day 10.

On Day 11 the row of bumps on my left leg developed into small blisters perhaps 2mm across.  I went for a walk in my neighborhood, per my usual routine.  After about 20 minutes I noticed a sensation in the left lower leg area, looked down, and was shocked to find that the string of small blisters had blossomed and mostly coalesced into a single sausage-like blister; see the first picture in the panel below.  Needless to say I immediately returned home, called the advice nurse again, and got set up with a doctor appointment the next morning.  Meanwhile, that night I had my first episode of intense prickly itching.  I am truly thankful that I haven’t had many more such episodes, though I have had a few.

On Day 12 my doctor, with dermatologist concurrence, put me on prednisone, which is a corticosteroid medication that calms the immune system response that is responsible for the rash.  I also received a prescription for prophylactic antibiotics, due to risk of infection due to open blisters and my concern about provoking any kind of secondary infection that might affect my hip.  The dermatologist recommended an oatmeal powder for the cool compresses and a different lotion that contains calamine and oatmeal.  By this time I understood that large blisters that (can) ooze large amounts of fluid are considered a sufficiently serious symptom/reaction to be a good reason to go beyond home treatment and see one’s doctor.

By the time I’d been on the prednisone for only a day, I felt that my system reaction was already starting to calm down.  Each person may react differently to a medication, but in this case I’d say it brought me blessed relief: the rash continued to spread for a few more days, but the crescendo certainly seemed diminished.  During the next few days I was highly focused – that terrified fascination again – on the sausage blister on my left leg, which got even bigger, turned slightly red, and then started to empty a bit at a time over 4 or 5 days.

pictures of blister on left leg

Blister on left leg

Meanwhile the original area on my right leg had spread considerably, become an angry-looking red, and developed a less-dramatic blister.

picture of rash on right leg

Rash on right leg

Gradually, as the prednisone has done its magic, the redness and most of the bumps elsewhere on my legs and wrists have calmed down and diminished.  I improvised a few techniques to keep my legs cool without chilling my body core.  This was nontrivial, as I learned one night at oh-dark-thirty when I found myself simultaneously shivering while my legs practically screamed with prickly-heat itch: an experience I hope not to repeat!

Not surprisingly, I took a few rest days from my usual walking routine and physical therapy exercises.  The various medications and treatments seemed to end up in a rather complicated schedule, as I tried to get each item relatively equally spaced across a 24-hour day: 4 of this, 3 of that, 2 of something else.

Now it is Day 19.  I find myself gauging my skin’s recovery by which pants are comfortable (or not) to wear.   I’ve resumed my daily walking and physical therapy routine but plan to stay away from the gym until all of the blisters have dried up and healed.  The big one on my right shin is neither oozing nor subsiding yet, so the final healing does not seem imminent.  As is typical the prednisone dosage is on a gradual taper, and I’m hopeful that there won’t be a rebound after I finish the regimen.  Stay tuned for a concluding post later.

This entry was posted in poison oak and tagged . Bookmark the permalink.

8 Responses to Poison Oak Rash Progression: Case Study

  1. Pingback: Hiker’s Nightmare: Poison Oak | trailhiker

  2. Wendy says:

    two other things that I find helpful topically, prednisone or not, is FRESH aloe, and sometimes a minty soap (like dr. bronners) can cool things when the heat feels unbearable. Wishing you a quick recovery, the prednisone definitely helps!

  3. Pingback: Poison Oak: All’s Well That Ends Well | trailhiker

  4. JulieO says:

    Thank you for posting this and sharing your experience! I am in the process of a similar experience, and am on day 33. My husband and I hiked the Rogue River the end of August – where there is poison oak everywhere! Day four I began getting a little itchy, day 6 spots began popping up, and day 9 spots broke out over my entire body – concentrating around an area on my thigh. Unfortunately, I don’t remember coming in contact with poison oak, and because of the very delayed response and the fact that my blisters remained small, my doctor ruled it out. We treated it as an allergic reaction, and I was put on Predisone – but as soon as I went off of it (after two weeks) the spots cam roaring back…… Long story short – three doctors visits and one dermatologist visit later, we concluded it is probably poison oak and I am being treated accordingly (with a cream and an H2 blocker). The derm’s other guess is that it might be lime disease, and wanted to put me on antibiotics. However, because I am confident we didn’t see any ticks, I chose not to go on them. Your post has made me confident that it IS poison oak – with your very similar delayed reaction. THANK YOU!

    • trailhiker says:

      I’m glad you are getting appropriate treatment. Though poison oak does NOT spread within the body through the blood stream, if you don’t know about the contact and therefore don’t clean up thoroughly afterward, you can unwittingly spread urushiol oil residue on yourself in all kinds of places. Since my reaction I have been much more aware of plants along the trails where I hike, and I’m also much more diligent about post-hike cleanup. Once you know you’re allergic, when in doubt about exposure, assume it happened and decontaminate appropriately. But if you’re aware and careful, there’s no need to curtail the hiking you enjoy.

  5. Melinda Bedrossian says:

    Dealing with poison ivy on hand, arm, face and neck. Face swollen and blisters. Less than a week. Still breaking out in different places on body. Never had allergy before

    • trailhiker says:

      Ouch! That sounds uncomfortable, especially on the face. The rash can continue to spread to new areas for several days. My outbreak peaked in intensity at something like 2 weeks, but that was also after I saw my doctor who prescribed prednisone to calm down my immune response. Good luck! I hope you find relief soon.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.