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Dr. Efren Rael

Allergy and Immunology
San Francisco, CA
19 years experience male

Locations

CPMC/Stanford LPCH

San Francisco, CA

Address

3700 Sacramento Street, Suite B555, San Francisco, CA, US
Directions

My office hours

Wednesday: Closed
Show more

Insurances accepted

Blue Cross of California

About

Bio

Dr. Rael is double board certified by the American Board of Internal Medicine and the American Board of Allergy and Immunology . He is on faculty in Allergy/Immunology at Stanford after 5 years on faculty at Penn State in Allergy/Immunology. He graduated from Boston University School of Medicine, completed internship at UCLA, medicine residency at Lahey Clinic, and fellowship at the University of South Florida under 2 prior presidents of the American Academy of Allergy and Immunology.

Specialties
Doctors may have more than one area of specialty interest. Board certification in a specialty area means the doctor has completed formal training and has practice experience in that specialty, and has passed the certification examination from the corresponding accredited medical specialty board.

Allergy and Immunology

Licenses

United States: California

Languages spoken

English

Doctor Q&A

42 Answers
0 Agrees
The number of answers this doctor has agreed with.
A 49-year-old member asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Allergy shots: I view allergy shot side effects in 2 categories: 1. local reactions and 2. systemic reactions. Systemic reactions can be life threatening and are m... Read More
A 37-year-old member asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Options: If it is easy to identify the soap brand associated with the allergy, avoidance is the best option. However, soaps can have a lot of chemicals that c... Read More
A 32-year-old male asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Possible allergy: Humidifiers, although moisturizing to humans, can also increase dust mite and mold populations and can sometimes paradoxically worsen allergy symptoms... Read More
A 34-year-old female asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Yes: Yes, my research and experience suggests, suboptimal response if treating asthma independent of allergic rhinitis or vice versa. Coexisting condition... Read More
A 32-year-old member asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
IgM: IgM is an antibody that is produced in response, such as to an infection, with subsequent switching to a more customized antibody such as IgG antibody... Read More
A 50-year-old member asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Symptoms: Opiate containing pain medications such as morphine, percocet, demerol, (meperidine hydrochloride) can cause mast cell degranulation independent of al... Read More
A 19-year-old male asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Neti Pot: Generally, use of the Neti Pot with sterilized/bottled, room temperature water is low risk. There has been a report of brain infection with use of ta... Read More
A 20-year-old female asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Depends: Yes, if allergies are triggering the post nasal drip. No if gastroesophageal reflux is triggering the post nasal drip.
A 42-year-old member asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Usually partially: Antihistamines partially block immune responses such as those associated with allergy. Usually in the setting of allergy, the immune system diversifie... Read More
A 41-year-old male asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Yes: Usually, there is no interaction with famotidine and nyquil or tylenol (acetaminophen) PM. Some recommend avoiding the combination with a different p... Read More
A 33-year-old female asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Possible thought: On the positive side, these symptoms are common early in life, and tend to resolve with time. A possible approach might be to get allergy testing for... Read More
A 35-year-old male asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
CD markers: CD stands for cluster of differentiation and can help distinguish cell types. CD8+ usually identifies a cell as a killer T cell. CD8- identifies a ... Read More
A 35-year-old male asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Propranolol: Thanks for your question. Propranolol can be used for a condition called essential tremor per the 2005 and 2011 American Academy of Neurology publish... Read More
A 31-year-old female asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Yes: Yes, Zyrtec (cetirizine) can become ineffective after a while. Zyrtec (cetirizine) tends to block histamine responses; however, the immune system div... Read More
A female asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Med Formulation: A lot of literature is emerging suggesting a link with the thyroid and skin symptoms such as itch/hives. Some formulations of thyroid medications can... Read More
A 32-year-old member asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Delayed vs Immediate: Immediate allergic reactions are typically responses associated with quick allergy mediators such as mast cells, basophils & eosinophils and usual... Read More
A 50-year-old member asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Challenging: Contact dermatitis to p-phenylene diamine is one of the most common allergies to hair dye. Symptoms are usually a red itchy rash that persists someti... Read More
A 19-year-old female asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Allergy: Consider allergy testing with an allergy specialist. Testing can involve skin or blood testing to environmental allergens. Typical winter and summ... Read More
A 45-year-old member asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Multifactorial: Allergies are associated with both environmental and genetic factors. Usually there are 2 phases to allergy, a sensitization phase and an effector ph... Read More
A 35-year-old male asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Allergy eye drops: There are many classes of allergy eye drops from drops that are antihistamines, anti-inflammatory, combination of 2 drugs, emollients and blood vessel... Read More
A 51-year-old member asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
One thought: Humidity can increase vegetation and growth of bacteria, mold, dust mites potentially creating a reactive response by the immune system to challenge, ... Read More
A 28-year-old female asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Hives discussion: Hives are usually not worrisome, unless associated with other features, such as pain/pressure (as opposed to itch), fever, unintentional weight loss, ... Read More
A 24-year-old female asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Allergy medicines: It is often a personal choice based on risks/benefits and indication. Allegra and Claritin (loratadine) are marketed as non-sedating. The package la... Read More
A 41-year-old member asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Yes: Yes, the stomach can hurt if you are allergic to something, usually if ingested. Other common symptoms are itch, hives, swelling, asthma, light heade... Read More
A 46-year-old member asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Allergic rash: The most common negative effect is a rash, that can be persistent for up to a month called contact dermatitis. The treatment of choice for contact de... Read More
A 45-year-old female asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Possible answer: Systemic symptoms are common. Fatigue, fever, and weight loss are typically present at some time during the course of the disease, occurring in 50 to... Read More
A 35-year-old member asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Allergy skin testing: In the U.S., after antihistamine avoidance, 2 methods are often used--the prick/puncture (SPT) 1st, and sometimes the intradermal (IDT) 2nd. SPT inv... Read More
A 40-year-old member asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Consider allergy ref: Thanks for your question. Depending on the NSAID allergy, sometimes it can be desensitized through introduction of small amounts initially, then grad... Read More
A 21-year-old male asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Salicylates : Salicylate acid exfoliants can sometimes cause an irritant skin reaction. Futhrmore, a subset of individuals can develop allergy to these products. ... Read More
A 29-year-old female asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
HepA filter: Air filters in studies, have modest effects in allergy treatment. A study combining Hepa filters with dust mite prevention, and pet avoidance showed... Read More
A 41-year-old member asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Innate immune system: The innate immune system recognizes patterns so as to respond quickly to challenge. Coding for pattern recognition is hard wired into our DNA, though... Read More
A 24-year-old female asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Possible answer: Grass allergy can cause itch. However, irritation of the skin can also cause itch. Given that the immune system has memory in the setting of allerg... Read More
A 36-year-old member asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Immune cells: Natural killer cells are immune effector cells that are efficient in killing virus infected cells. They can be divided into 2 sets: CD56bright (produ... Read More
A 51-year-old member asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Metal allergy: The most common metals associated with contact dermatitis allergy are nickel, cobalt, gold sodium thiosulphate. The T.R.U.E. Test can help clarify if... Read More
A female asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Yes: Generally yes. However, benzonatate can cause drowsiness. The first generation antihistamines (such as benadryl, (diphenhydramine) doxepin, chlorphe... Read More
A 40-year-old member asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Food allergy & skin: The most common relationship between food allergy and the skin are hives (marked by raised red bumps that are red and itchy that occur quickly and res... Read More
A 37-year-old member asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Lots: There are a lot of things that can weaken the immune system including medications to treat autoimmune disease, prevent transplant rejection, steroids,... Read More
A 51-year-old member asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Non hereditary forms: Stress associated has been reported and industrial chemical induced by hydroquinone mono methyl ether and to paratertiary-amyl-phenol,
A 46-year-old member asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Alcohol and allergy: I try to distinguish if: 1. it is a type of alcohol causing symptoms, 2. if alcohol is facilitating the response to an allergen, or 3. if it is a sid... Read More
A 26-year-old male asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
2 is better: Anaphylaxis treatment can be unpredictable and sometimes requires 2 doses or more of epi. Hence, if the 1st dose isn't successful at reversing anaph... Read More
A 49-year-old member asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
Quantification: Radial immunodiffusion can help detect quantity or concentration of a protein. The benefit is that it is relatively inexpensive to perform and pretty... Read More
A 29-year-old female asked:
Dr. Efren Rael
Allergy and Immunology 19 years experience
RAST test: RAST, is less commonly used, as it involves radiation to detect allergic antibodies in the blood. A more common test is immunocap testing which does ... Read More

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Testimonials
Recommendations and Thank you notes are endorsements given from patients or other doctors.

18
Thank you notes
HealthTap member
Thank you, your answer was very helpful! Great answer, exactly what I was looking for! Thank you :)
HealthTap member
Thank you, your quick reply made me feel good!
HealthTap member
Thank you, your answer was very helpful!

Education & Training

Medical/Graduate school

Boston University School of Medicine, MA
Graduated 2003MD

Residency

LAHEY CLINIC HOSPITAL

Awards

Scientific Research Travel Scholarship, American Academy of Allergy, Asthma, and Immunology (AAAAI)

Affiliations

Stanford University Hospital & Clinics, Palo Alto, CA
90,000 U.S. doctors in 147 specialties are here to answer your questions, provide medical advice, write prescriptions, and more.
Answer emailed
in 24 hours or less