Are you having back pain with any of the following?

  • Severe pain, weakness or tingling in your leg(s).
  • Difficulty stopping urination or loss of control of bladder or bowels.
  • Unexplained fever, nausea or vomiting.
  • A history of cancer or unexplained weight loss.

We understand that you are experiencing one or more of the health issues that might be impacting your back pain.

We recommend that you discuss these health issues with your doctor before proceeding with this program.

Once you are cleared by your doctor to do this program, we hope it helps you find relief from your back pain.

Provider photo for Jonathan Volk

Jonathan Volk, MD

Infectious Diseases

Welcome to My Doctor Online, a web site that my colleagues and I developed to make it easier for you to take care of your healthcare needs. On this site you will find answers to many of your questions about my clinical practice. Also included are several online features that will allow you to e-mail me, check your laboratory results and refill prescriptions. I hope you find its content informative and useful.

My Offices

San Francisco Medical Center
Appt/Advice: 415-833-2200

See all office information »

subContentURL_nobackslash = resources/dc/condition

firstActiveTabUrlFragment = resources/dc/conditionlist

subContentURL_nobackslash = resources/dc/condition

JSP2Include = /mdo/presentation/conditions/condition.jsp?nocache=true


Chickenpox is an infection caused by a virus (varicella-zoster). It’s easily spread from person to person. We usually see chickenpox in children age 15 years and younger, but adults can get it too.

Symptoms last about 5 to 15 days and include:

  • An itchy, blistering rash
  • Fever
  • Headache

The rash:

  • Appears 10 to 21 days after exposure to the virus.
  • Produces small, fluid-filled blisters that break open and form crusts.

When first infected, you or your child might not have symptoms. During this time, you can spread the virus to others without knowing it. You’re contagious until 1 to 2 days before the rash appears.

Home treatment helps reduce itching and eases other symptoms. We may also prescribe antiviral medicine. Be sure to let us know if you or your child has chickenpox symptoms.


The first symptoms of chickenpox are fever, stomachache, headache, or loss of appetite.

Within 2 to 4 days, you develop a rash with fluid-filled blisters. It begins on the trunk, face, and scalp, then spreads over the body.

Within 1 or 2 days after the first blisters appear:

  • They burst and scab over.
  • New blisters develop in cycles.

Blisters can appear:

  • Inside the mouth
  • On the eyelids
  • Inside the ears
  • On the genitals, or inside the vagina

Unless you or your child scratches and infects the blisters, you won’t have scars after the blisters heal.

Children and adults who have eczema may have more severe blisters.

Symptoms usually last 5 to 15 days.

Possible Complications

Call us right away if you think your child (or you) has chickenpox. Blisters can become infected. This makes treatment more difficult and may make the illness last longer.

Early treatment can reduce the risk of rare but serious complications, such as:

  • Pneumonia
  • Arthritis
  • Heart infection (myocarditis)

Once you have chickenpox, the virus remains inactive (dormant) in your body after you get well. It can be triggered later in life, causing a condition called shingles.

Risk Factors

You and your child are at highest risk of getting chickenpox if you:

  • Haven’t had the chickenpox vaccine.
  • Have a weakened immune system (such as from chronic illness or medicine like steroids).

If an adult or child who is vaccinated develops chickenpox, the symptoms are usually mild. But they can still pass chickenpox to others.

Causes and Diagnosis

Chickenpox is caused by the varicella-zoster virus. It spreads when an infected person sneezes or coughs.

You or your child can be infected when you:

  • Breathe in the virus
  • Touch the fluid from blisters

You’re most contagious 1 to 2 days before the rash appears. You or your child might not have any symptoms yet. You might not realize that you’re spreading the virus to others.

We diagnose chickenpox by looking at the rash with blisters. If it’s not clear, we might order a blood test to confirm the diagnosis.

When a pregnant woman gets chickenpox, she may pass the infection on to her unborn baby. Chickenpox is usually severe in a newborn, especially if the mother hasn’t had it or been vaccinated.


The chickenpox vaccine is our best prevention tool.

Children get 2 vaccine doses at:

  • 12 to 15 months old.
  • 4 to 6 years old.

For children ages 12 months through 12 years, the second dose is given 3 months or more after the first dose.

For people age 13 years and older, the second dose is given 4 weeks or more after the first.

If you or your child were recently exposed to chickenpox and haven’t been vaccinated, we may recommend vaccination. This may prevent chickenpox or make symptoms milder.

Do not get the chickenpox vaccine if you:

  • Are pregnant.
  • Had an allergic reaction to a previous chickenpox vaccine.
  • Are already immune to chickenpox.
  • Have a severely weakened immune system.

If you have a weakened immune system, let us know before being vaccinated.

Home Treatment

Home treatment can soothe your child’s chickenpox symptoms. It’s usually all the care that is needed.

Reduce your child’s itching with an:

  • Oatmeal bath in lukewarm water.
  • Anti-itching lotion (Calamine).
  • Oral antihistamine, such as Benadryl.

To soothe other symptoms:

  • Reduce fever or pain with acetaminophen or ibuprofen.
  • Keep the fingernails trimmed short. Scratching the blisters can cause an infection.
  • Make sure your child gets plenty of rest, especially during the fever phase.

Do not give aspirin to a child with chickenpox. It can cause a serious condition called Reye's syndrome. If your child takes daily aspirin for another condition, let us know.

If you haven’t had chickenpox or been vaccinated, don’t take care of someone who has chickenpox.

Avoid touching the fluid from your child’s blisters. It could infect you with the chickenpox virus.

Don’t let your child return to school or play with other children until all the blisters have dried out or become crusty.

An adult should not return to work or public places until his or her chickenpox blisters crust over.

Treatment and Medications

We may prescribe an antiviral medication if your child or you have:

  • Severe chickenpox
  • Eczema
  • Another skin condition
  • A weakened immune system

Antiviral medication is most effective when taken within 72 hours after the rash first appears.

We might also give family members antiviral medication to prevent an outbreak in your home.

When to Call Us

If you think your child (or you) was exposed to chickenpox, and you haven’t had chickenpox or the vaccine, call us. You'll need to be vaccinated right away.

If your child (or you) develops a rash of fluid-filled blisters, call us. Most children do not need treatment. We can determine if treatment is needed for your child and others in your household.

Your Care with Me

If you are having symptoms that concern you, your first contact will typically be with your personal physician, who will evaluate your health and symptoms.

If specialty care is needed, your personal physician will facilitate the process of scheduling an appointment in my department. If appropriate, she or he might call me or one of my colleagues while you are in the office so we can all discuss your care together. If we decide you need an appointment with me after that discussion, we can often schedule it the same day or soon thereafter.

During your office visit, we will discuss your medical and family history and I will perform a physical exam. I will explain the findings of your exam and answer any questions or concerns you may have. We will discuss treatment options and develop a treatment plan that is right for you.

If you need to talk with me after your visit or procedure, please call my office. You can also e-mail me with nonurgent issues from this website whenever it is convenient for you.

For general medical advice, our Appointment and Advice line is available 24 hours per day, 7 days per week.

If you have urgent concerns or issues while my office is closed, or need general medical advice, you can call the Appointment and Advice line. You will be connected with a nurse who can give you immediate advice.

If you are experiencing a serious problem or an emergency, call 911 or go to the nearest Emergency Room when the clinic is not open.

Coordinating Your Care

Having all of our Kaiser Permanente departments located together or nearby, including pharmacy, laboratory, radiology, and health education, makes getting your care easier for you.

Another major benefit is our comprehensive electronic medical record system, which allows all of the doctors and clinicians involved in your care to stay connected on your health status and collaborate with each other as appropriate.

When every member of the health care team is aware of all aspects of your condition, care is safer and more effective.

If you come to an office visit
  • At the beginning of your visit, you will receive information about when you are due for your next test, screening, or immunization. We can discuss and schedule any preventive tests that you need. 
  • At the end of your visit, you may receive a document called the “After Visit Summary” that will summarize the issues we discussed during your visit. You can refer to it if you forget what we discussed, or if you just want to recheck your vital signs and weight. You can also view it online under Past Visits.
  • To help you prepare for your visit, please see additional details under Office Visit. 
If I prescribe medications

We will work together to monitor and assess how your medications are working and make adjustments over time. Prescriptions can be filled at any Kaiser Permanente pharmacy. Just let me know which pharmacy works best for you, and I will send the prescription electronically in advance of your arrival at the pharmacy.

If refills are needed in the future, you can:

  • Order them online or by phone. Order future refills from my home page or by phone using the pharmacy refill number on your prescription label.
  • Have them delivered to you by mail at no extra cost. Or you can pick up your medications at the pharmacy. If no refills remain when you place your order, the pharmacy will contact me regarding your prescription.
If lab testing or imaging is needed

For lab tests, I will use our electronic medical record system to send the requisition to the Kaiser Permanente laboratory of your choice. For imaging procedures, we will schedule an appointment with the Radiology department. When the results are ready, I will contact you with your results by letter, secure e-mail message, or phone. In addition, you can view most of your laboratory results online, along with any comments that I have attached to explain them.

If I refer you to another specialty colleague

If we decide together that your condition would also benefit from the care of other types of specialists, our staff will help arrange the appointment(s) with one or more of my specialty colleagues.

If surgery or a procedure is a treatment option

I will recommend that you review educational information and tools to help you prepare for your procedure or surgery. The information will often help you decide whether surgery is right for you. If you decide to have a surgery or procedure, the information will provide details about how to prepare and what to expect.

If we proceed with surgery, I will have my Surgery Scheduler contact you to determine a surgery date and provide you with additional instructions regarding your procedure. Once your surgery is scheduled, a medical colleague of mine will contact you to conduct a preoperative medical evaluation that will assure that you are properly prepared for your surgery.

Convenient Resources for You

As your specialist, I have a goal to provide high-quality care and to offer you choices that make your health care convenient. I recommend that you become familiar with the many resources we offer so that you can choose the services that work best for you.

My Doctor Online is available at any time that is most convenient for you. From my home page you can:

Manage your care securely
  • View and compose secure e-mail messages.
  • Manage your prescriptions.
  • View your past visits and test results.
  • View your preventive services to see whether you are due for a routine screening or updated immunization.
Learn more about your condition
  • Read about causes, symptoms, treatments, and procedures.
  • Find interactive health tools, videos, and podcasts to help you manage your condition.
  • View programs to help you decide on or prepare for a surgery or procedure.
Stay healthy
  • Locate health education classes and support groups offered at every medical center.
  • Explore interactive programs, videos, and podcasts that focus on helping you stay healthy.
  • View your Preventive Services to see whether you are due for a routine screening or updated immunization.

If you have an emergency medical condition, call 911 or go to the nearest hospital. An emergency medical condition is any of the following: (1) a medical condition that manifests itself by acute symptoms of sufficient severity (including severe pain) such that you could reasonably expect the absence of immediate medical attention to result in serious jeopardy to your health or body functions or organs; (2) active labor when there isn't enough time for safe transfer to a Plan hospital (or designated hospital) before delivery, or if transfer poses a threat to your (or your unborn child's) health and safety, or (3) a mental disorder that manifests itself by acute symptoms of sufficient severity such that either you are an immediate danger to yourself or others, or you are not immediately able to provide for, or use, food, shelter, or clothing, due to the mental disorder.

This information is not intended to diagnose health problems or to take the place of specific medical advice or care you receive from your physician or other health care professional. If you have persistent health problems, or if you have additional questions, please consult with your doctor. If you have questions or need more information about your medication, please speak to your pharmacist. Kaiser Permanente does not endorse the medications or products mentioned. Any trade names listed are for easy identification only.

Content loading spinner