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Testing Intake

Skin Prick Testing

In-clinic allergy testing with results typically available same day.

Prepantihistamine holdindicationswhat to expectinterpretation

Overview

Skin prick testing (SPT) is the most common and reliable method for diagnosing allergic sensitization. It's quick, relatively painless, and provides results within 15-20 minutes.

prep

medications

hold

  • Oral antihistamines: Stop 5-7 days before testing
  • Topical antihistamines: Avoid on testing area
  • Tricyclic antidepressants: May need to hold (discuss with provider)
  • H2 blockers: Usually okay, but discuss with provider

okay

  • Nasal steroids: Continue as normal
  • Inhaled medications: Continue as normal
  • Most other medications: Usually fine

day Of

  • Eat normally (no fasting required)
  • Wear comfortable clothing
  • Avoid applying lotions or creams to arms/back
  • Bring list of current medications

indications

  • Suspected allergic rhinitis
  • Food allergy evaluation
  • Insect sting allergy
  • Medication allergy (selected cases)
  • Occupational allergy
  • Asthma with suspected allergic triggers

what To Expect

process

  • Small drops of allergen extracts placed on skin (usually forearm or back)
  • Light prick through each drop with sterile lancet
  • Minimal discomfort - feels like light scratch
  • Wait 15-20 minutes for reaction
  • Measure any raised bumps (wheals) that develop

duration

Total appointment time: 30-60 minutes

reactions

  • Positive reactions: Raised, itchy bump (wheal) at test site
  • Negative reactions: No significant reaction
  • Control tests: Histamine (should react) and saline (should not react)

interpretation

positive

  • Wheal size of 3mm or larger than negative control
  • Indicates sensitization to that allergen
  • Must correlate with clinical history to confirm allergy
  • Larger wheal doesn't always mean more severe allergy

negative

  • No significant reaction
  • Suggests no IgE-mediated sensitization
  • Doesn't rule out non-IgE mediated reactions

factors

  • Wheal size
  • Clinical history
  • Symptoms with exposure
  • Other test results

limitations

  • Cannot test if patient has severe eczema or dermatographism
  • May be less reliable in very young children
  • Results must be interpreted in context of clinical history
  • Doesn't predict severity of reactions

after Care

  • Mild itching at test sites is normal
  • Can use topical antihistamine or hydrocortisone if needed
  • Avoid scratching test sites
  • Reactions typically resolve within hours

Ready to Get Started?

Schedule a consultation to discuss your specific needs and create a personalized treatment plan.