- Itching, pain, or swelling from an insect bite
- Itchy Insect Bites: Bites of mosquitoes, chiggers (harvest mites), fleas, and bedbugs usually cause itchy, red bumps
- Painful Insect Bites: Bites of horseflies, black flies, deer flies, gnats, harvester ants, blister beetles, and centipedes usually cause a painful, red bump. Within a few hours, fire ant bites can change to blisters or pimples
- Anaphylaxis is the medical term for a severe life-threatening allergic reaction.
- Symptoms of anaphylaxis include: feeling faint or passing out, difficulty breathing, swelling of the tongue, hives, wheezing and/or cough. Onset of symptoms is sometimes within seconds and usually within 20 minutes.
- Individuals who have had severe reactions to previous stings should have an anaphylaxis kit (e.g., Ana-Kit, Epi-Pen) and keep it nearby if there is any risk of a sting.
- Anaphylaxis can occur following fire ant stings, but rarely with other insects. It mainly occurs with bee, yellow jacket or wasp stings.
- Wear long pants and long-sleeved shirts.
- Avoid being outside when the insect is most active. Many insects that cause itchy bites are most active at sunrise or sunset (e.g., Chiggers, No-See-Ums, Mosquitoes).
- Insect repellents containing DEET also seem to be effective in preventing many itchy insect bites. Read the label carefully.
See More Appropriate Topic (instead of this one) If
FIRST AID ADVICE for Anaphylaxis - Epinephrine (pending EMS arrival):
- If the patient has an epinephrine autoinjector, the patient should use it now.
- Use the autoinjector on the upper outer thigh. You may give it through clothing if necessary.
Epinephrine is available in autoinjectors under trade names: Epi-Pen, Epi-Pen Jr, and Twinject. Epi-Pen is a single injection. Twinject has a second injection that can be used if there is no improvement after 5 minutes.
FIRST AID ADVICE for Anaphylaxis - Benadryl (pending EMS arrival):
- Give antihistamine orally NOW if able to swallow.
- Use Benadryl (diphenhydramine; adult dose 50 mg) or any other available antihistamine.
FIRST AID ADVICE for Anaphylactic Shock (pending EMS arrival):
- Lie down with feet elevated.
Should I Call?
WHEN TO CALL YOUR DOCTOR
Call 911 Now (you may need an ambulance) If
- Passed out (fainted)
- Difficult to awaken or acting confused
- Wheezing or difficulty breathing
- Hoarseness, cough or tightness in the throat or chest
- Swollen tongue or difficulty swallowing
- Previous severe allergic reaction same insect bite (not just hives or swelling)
- Note: Symptoms above may indicate anaphylaxis. Anaphylaxis usually starts within 20 minutes, and always by 2 hours following a sting. See First Aid.
Call Your Doctor Now (night or day) If
- You feel weak or very sick
- Hives or swelling elsewhere on the body
- Fever and bite looks infected (i.e. spreading redness, pus)
Call Your Doctor Within 24 Hours (between 9 am and 4 pm) If
- You think you need to be seen
- Painful bite and not improved after 24 hours
- New redness or red streak occurs around the bite after the first 24 hours
- Scab that looks infected (drains pus or increases in size) not improved after applying antibiotic ointment for 2 days
Call Your Doctor During Weekday Office Hours If
- You have other questions or concerns
Self Care at Home If
- Normal insect bite and you don't think you need to be seen
Care at Home
HOME CARE ADVICE
Treatment for Insect Bites
- Local Treatment - Itchy Insect Bites (including all mosquito bites)
- Apply calamine lotion or a baking soda paste.
- If the itch is severe, use 1% hydrocortisone cream. Apply 4 times a day until the itch is less severe, then switch to calamine lotion.
- Try applying firm, sharp, direct, steady pressure to the bite for 10 seconds. A fingernail, pen cap, or other object can be used.
- Oral Antihistamine Medication for Severe Itching: Take an antihistamine by mouth to reduce the itching. Diphenhydramine (Benadryl) is a good choice. The adult dosage of Benadryl is 25-50 mg by mouth and you can take it up to 4 times a day.
- Do not take antihistamine medications if you have prostate enlargement.
- Antihistamines may cause sleepiness. Do not drink, drive or operate dangerous machinery while taking antihistamines.
- An over-the-counter antihistamine that causes less sleepiness is loratadine (e.g., Alavert or Claritin).
- Read the package instructions thoroughly on all medications that you take.
- Local Treatment - Painful Insect Bites
- Rub the bite for 15 to 20 minutes with a cotton ball soaked in a meat tenderizer solution. This will usually relieve the pain (Caution: don't use near the eye).
- If not available, use a baking soda solution on a cotton ball.
- If neither is available, apply an ice cube for 20 minutes.
- Pain Medicines:
- Antibiotic Ointment: If the insect bite has a scab on it and the scab looks infected, apply an antibiotic ointment 4 times per day.
- Cover the scab with a Band-Aid to prevent scratching and spread.
- Repeat washing the sore, the antibiotic ointment and the Band-Aid 4 times per day until healed.
- Expected Course: Most insect bites itch or hurt for 1 to 2 days. The swelling may last a week.
- Call Your Doctor If:
- Severe pain persists more than 2 hours after pain medicine
- Infected scab doesn't look better after 48 hours of antibiotic ointment.
- Bite looks infected (redness, red streaks, increased tenderness)
- You become worse
- Symptoms of WNV:
- Diagnosis of WNV:
- Treatment of WNV:
- WNV - Spread by Mosquito:
- DEET - An Insect Repellent
- Picaridin(also called KBR 3023):
And remember, contact your doctor if you develop any of the "Call Your Doctor" symptoms.
The photo shows a female mosquito feeding on a human host.
Source: CDC PHIL
From the CDC's Public Health Image Library (http://phil.cdc.gov), ID#1863, in the public domain.
Photo credit: James Gathany.
Author and Senior Reviewer: David A. Thompson, M.D. Clinical content review provided by Senior Reviewer and Healthpoint Medical Network.
Last Review Date: 11/18/2011
Last Revised: 11/18/2011
Content Set: Adult HouseCalls Symptom Checker
Version Year: 2012
Portions Copyright 2000-2012 Self Care Decisions LLC; Copyright LMS, Inc.