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Dr. Karen Han

Dermatology
Palo Alto, CA
24 years experience

Locations

Palo Alto Medical Foundation

Palo Alto, CA

Address

795 El Camino Real, Palo Alto, CA
Directions

Practice website

About

Bio

Board certified dermatologist. I specialize in skin cancer detection, skin cancer surgeries and cosmetic dermatology, including lasers, Botox, and fillers. I also see general pediatric and adult dermatology including eczema, acne, rosacea, psoriasis, rashes, and other hair, nail and skin diseases.

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.

Dermatology

Languages spoken

English

Doctor Q&A

212 Answers
1 Agree
The number of answers this doctor has agreed with.
A 22-year-old female asked:
Dr. Karen Han
Dermatology 24 years experience
See your doctor: If a mole is changing or symptomatic (itch or bleed), you should see your doctor for evaluation and possible biopsy.
A 41-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
Dysplastic moles: Moles are proliferations of nevus cells. Most moles are benign. Some can transform into melanoma. Many believe that the transformation is gradual. ... Read More
A 18-year-old male asked:
Dr. Karen Han
Dermatology 24 years experience
Consider Botox: Excessive sweating (hyperhidrosis) can be treated conventionally with aluminum chloride solution. The key is to apply the aluminum chloride solution ... Read More
A 28-year-old female asked:
Dr. Karen Han
Dermatology 24 years experience
Rogaine (minoxidil) : Greying and hair loss are two different processes. Rogaine (minoxidil) works for hereditary androgenetic alopecia (hair loss). It prevents cycling of... Read More
A 27-year-old female asked:
Dr. Karen Han
Dermatology 24 years experience
Depending on cause: If your hematoma developed after a surgery, we tend to treat it with oral antibiotics as the would has been exposed and you'd have a higher risk of in... Read More
A female asked:
Dr. Karen Han
Dermatology 24 years experience
No: Co2 laser resurfacing removes a layer of skin in a controlled fashion. In some cases, patients with extensive precancers can be treated with co2 lase... Read More
A 20-year-old female asked:
Dr. Karen Han
Dermatology 24 years experience
Alopecia Areata: From your description, you might have alopecia areata (aa). You should see a dermatologist for evaluation for verification. Aa is an autoimmune diso... Read More
A 21-year-old male asked:
Dr. Karen Han
Dermatology 24 years experience
The amount of loss: Stress induced hair loss occur in clumps and diffuse--ie. many hairs fall out at once on your comb, in the shower, on your pillow, etc. When your body... Read More
A female asked:
Dr. Karen Han
Dermatology 24 years experience
Itch: Scabies tend to create burrows and small red bumps in the skin, often found in underarms, belly button and inter digit web spaces. In infants, buttoc... Read More
A 45-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
No: Lemon and limes can cause an irritant reaction, especially with sun exposure. Lemon does not lighten you skin. Sun protection with sunscreens will r... Read More
A 31-year-old male asked:
Dr. Karen Han
Dermatology 24 years experience
No known solution: Pigmentation in follicles require proper 1)production of melanin (the pigment) and 2)the proper transfer of melanin into the follicles. If either of ... Read More
A 27-year-old female asked:
Dr. Karen Han
Dermatology 24 years experience
Intra-oral or lip?: My patients often use "fever blister" for all ulcers or erosions that occur in the mouth or on the lips. They are different. On the lips are typical... Read More
A 30-year-old male asked:
Dr. Karen Han
Dermatology 24 years experience
No cure: Dark circle under your eyes is not an excess pigmentation. The eyelid skin is very thin, any swelling (poor sleep, stress, allergies, age, etc) will ... Read More
A 27-year-old female asked:
Dr. Karen Han
Dermatology 24 years experience
Which product?: I would be interested to research this for you if you can be specific about which product that's been approved in the eu that has cell regeneration th... Read More
A 43-year-old female asked:
Dr. Karen Han
Dermatology 24 years experience
Likely colonization: Impetigo is a bacterial infection of the skin, most often caused by staph aureus. This bacteri is sometimes colonized in the nostrils of those with c... Read More
A 22-year-old female asked:
Dr. Karen Han
Dermatology 24 years experience
Oral Antiviral: "cold sores" on lips is caused by herpes simplex virus. One usually feels burning sensation before the blisters appear. If you start the oral antivir... Read More
A 31-year-old female asked:
Dr. Karen Han
Dermatology 24 years experience
No: It's ok to wash in the morning when you normally wake. By then, the applied tretinoin has already been absorbed.
A 48-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
See a dermatologist: Peeling skin on the feet can be fungus vs foot eczema vs psoriasis vs genetic vs other. Treatment depends on the diagnosis.
A 38-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
See your PCP: If you don't have a rash, and only the described symptoms above, there could be underlying systemic disorder causing your sensation, such as diabetes.... Read More
A 48-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
Allergy?: If you have been diligent with moisturizing your hands each time you wash, and your rash doesn't go away, you might have contact allergic dermatitis. ... Read More
A 21-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
Photorejuvenation: Ipl is a filtered light device that is effective in removing brown spots and blood vessels, good for treating sun damaged, acne and rosacea skin. With... Read More
A 21-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
Multiple: Melanoma risk factors include fair skin, history of sunburns, excessive uv exposure such as from tanning beds, living near the equator or at higher el... Read More
A 21-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
Yes: Smoking causes poor wound healing after any invasive procedure such as surgery, laser resurfacing, liposuction, etc..., including scar revision and mo... Read More
A 21-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
Yes: Patients with psoriasis have a higher risk of developing skin cancers and cardiovascular disease. For this reason, it is recommended that those with ... Read More
A 21-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
Exfoliants: Products containing salicylic (beta hydroxy) acids or Alpha hydroxy acids help acne skin. This may be in the form of face washes or leave-on products... Read More
A 21-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
No: Rosacea is a chronic inflammatory condition that waxes and wanes. It usually begins in adulthood, and when papules develop, some call it "adult acne"... Read More
A 22-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
Exfoliation: Chemical peels removes layers of skin. The strength/chemical determines the depth of the peel. It is generally used to cosmetically removed brown sp... Read More
A 27-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
Terbinafine: If you are certain that you have "ring worm", these are fungal infections that are primarily due to dermatophytes called t. Rubrum. I find that otc t... Read More
A 30-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
Photoprotection!: Skin of patients lupus erythematosus (le) is very sensitive to sun exposure, regardless of what subtype of lupus you might have. For this reason, i r... Read More
A 21-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
Ichthyosis: Ichthyosis (fish scale disease) is an inherited condition characterized by dry scaly skin as a result in defective skin barrier function. The most com... Read More
A 21-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
Oral antihistamines: Eczema is an inflammatory disorder driven by excessive histamine release, much like asthma and hay fever. Taking oral antihistamines, such as Claritin... Read More
A 21-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
No: Albinism is a genetic pigmentary disorder. The genetic defect that affects enzymes that are involving in pigment (melanin) production or distributive... Read More
A 21-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
Sal acid and Tar: Psoriatic scalp often is also colonized by a common yeast called pityrosporum ovale, which is the same yeast that causes dandruff. Treatment involves ... Read More
A 27-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
Inherited: Psoriasis is an inherited inflammatory condition that waxes and wanes. Treatment is generally directed towards control of symptomatic flares. Althoug... Read More
A 40-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
Antimicrobial: Silvadene (silver sulfadiazine) cream is antimicrobial, keeping pressure sores from becoming infected. In addition, the emollient (cream or ointment)... Read More
A 27-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
ABCDE's of mole chec: Atypical moles that resemble melanoma often has one or all of the following characteristics: a for asymmetry; b for irregular borders; c for lots of d... Read More
A 34-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
Inherited: Eczema is generally inherited. There is usually family history for eczema, asthma or hayfever, together we call atopy. These three conditions are es... Read More
A 37-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
Direct contact: Cold sores or herpes simplex virus infections. It is spread by direct contact with actively flared blistering lesions.
A 21-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
Both immunologic: Psoriasis and eczema are both immunological conditions that cause inflammation in the skin. Eczema is histamine driven and is related to hay fever and... Read More
A 24-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
Keratosis pilaris: Keratosis pilaris (rough pink bumps on upper arms and thighs) are thought to be in the spectrum of eczema with very dry skin and plugging of follicles... Read More
A 43-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
No: Rosacea is an inherited condition characterized by extra sensitive skin, flushing, dilated blood vessels, inflammatory bumps that mimic acne, and enla... Read More
A 21-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
Avoid allergens: Keeping your skin moist with bland lotions or ointments is essential. Common avoidable topical allergens include fragrances (organic or not), cocamid... Read More
A 24-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
No: Antibiotics target bacteria. Athletes foot is a fungal infection, which responds to antifungals.
A 21-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
Direct contact: Impetigo spreads by direct skin to skin contact.
A 21-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
No: Psoriasis is an inflammatory disorder that is inherited, although sporatic cases also occur. There is no way of preventing psoriasis from developing.... Read More
A 21-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
See specialist: This is an important question to discuss with your dermatologist. If the melanoma is 1-4mm thick, sln biopsy is often recommended. Between 0.7-1mm d... Read More
A 22-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
Sometimes...: We generally talk about lupus in 2 categories: systemic and cutaneous (localized in skin). A subtype of cutaneous lupus called discoid lupus can caus... Read More
A 21-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
No: We don't fully understand the pathophysiology of vitiligo. It is considered an autoimmune disorder, and sometimes associated with systemic autoimmune... Read More
A 40-year-old member asked:
Dr. Karen Han
Dermatology 24 years experience
Topical antibiotic: The bacteria that's commonly the cause of impetigo is staph aureus, which responds to prescription topical antibiotics. If your doctor determines tha... Read More

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

2
Recommendations
844
Thank you notes
HealthTap member
Mar 30, 2015
Dr. Han is an amazing doctor! #nationaldoctorsday2015 #virtualflower1
HealthTap member
Mar 31, 2015
Dr. Han is an amazing doctor! #nationaldoctorsday2015 #virtualflower1
HealthTap member
Thank you, your answer was very helpful! This is exactly my condition. Another doctor answered, but wanted more info on this in particular. Thanks!
HealthTap member
Thanks for your quick reply! Thank you for your feedback! It's embarrassing and frustrating, and I hate that I have to deal with it :(
HealthTap member
Thank you, your answer was very helpful! my problem started,when I was over 50 and nothing l do clears itn up for good. thanks

Education & Training

Medical/Graduate school

UC San Francisco School of Medicine, CA
Graduated 1996MD

Medical/Graduate school

Northwestern University Feinberg School of Medicine, IL
Graduated 1998MD

Residency

University of California, Los Angeles

Awards

Top Dermatologist , First Place, San Mateo County, CA - Winter
2013
HealthTap Founding Doctor
HealthTap ClubMD
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