Parents Beware. -If they tell you in the office to "ask billing," or "it depends on your insurance," then ask them for an itemized list of what will be done. They have it, just need to ask directly. Each visit has been $307 to see the Doctor for 7 minutes. It has been $582 to feed my toddler bites of food every 20 minutes - I made the food and gave it to my toddler, so we paid to "rent" the space for 2 hours and have the Nurse then look at their skin to see if it gets red after eating, and then the Doctor say "bye, see you next time!" -Dr. Marks has good table side manner, but spent 30 minutes TOTAL with us over 7 visits in 2024. Each of those visits cost $307. Our deductible is high so we asked for the cash price and paid "$270 up front for the year." We had to give our insurance information to book the visits. -4 months later we got a bill for that 1st appointment. hey went through our insurance, even AFTER we paid up front and were told it covered it. When I called they told me not to worry about it. "Oh sorry, it is an error on our part. We will take care of it." Every 3-4 months after one of our visits the same thing has happened. They wait 3 months to Bill you for your appointment. They keep going through our insurance even though we paid in cash and have asked for the cash price each time (cheaper than our Insurance price). I got a New Bill in the Mail this week (January 2025) for injections in July 2024, that we never received. -In my professional accounting experience Double Billing Fraud is only 1 reason to wait 6 months after an appointment to Bill insurance, and to use a different code/ reason for visit. You usually see this more with medical offices that have Senior Citizen clientele though. Charging my Credit Card, and then charging my insurance for the same appointment 6 months later is medical claims fraud in the state of California. Was not surprised to hear I am not the first one to file a claim. -I call the office AND Billing twice a week and also get the "this is how a deductible works..." speech. I have instructed them before and after each visit to bill me for the cash price, and not to Bill Insurance. read more

Poor care, mismanaged office, and wild billing practices. Go elsewhere. TL;DR- you're going to receive care from the nurses, not the doctor. They're going screw up the bill. It will drive you bananas just trying to pay for an overpriced visit where you barely saw a doctor. I am not a fan. I recommend trying a different doctor. I had an appointment for my infant in 2023. We waited weeks, maybe months for an appointment. Shortly before our appt they called to reschedule us because the doctor had a conference. I bring my baby to the rescheduled appointment and we spend 95% of the time with the nurse. The doctor is late, pops in for 5 minutes, tells me the nurse has explained everything perfectly. Wait, what? Dr Marks is running her practice on nurses doing the work and her "supervising." Flash forward to almost a year later I get a call saying that they're going to send me to collections. I never received a bill. When I call the office to clarify it's clear there has been a typo on my address. I update my contact information and ask for a bill to be sent. They tell me the bill amount and then add an extra charge, but can't really explain why. I go back and forth with the office and attempt to pay the bill, giving them my credit card. They never ran the card. A month later I got a new card because of a fraud alert. Now they choose to run the card and it's declined. After another back and forth I give them a new card and think that's done. Flash forward December 2025, 2 years after the appointment, after multiple attempts to pay this stupid bill, they call to say "we are sending you to collections. You haven't responded to our attempts to collect." What attempts? This is the first I've heard of it. Now I have to go through a year of credit card payments to see if they did or didn't run the card back in 2024? I do not recommend. read more

Very disappointing consultation experience. We had a 10 minute video consultation with Dr. Marks Cogan to determine if my child should be tested for allergies. Ultimately, it was decided it wasn't a fit. We then received a bill for $377 after being told we don't qualify for her services. I don't recommend using Clear Allergy if you aren't 100% sure you have allergies as you will be charged. I wish I would have read the reviews before hand because it seems to be a common issue with this office. read more

Their billing practice is a total scam. When we first brought my infant to Dr Marks for allergy testing/treatment, we made it clear that we had a high deductible insurance plan and they told us it would be cheaper for us not to go through insurance and to pay a few hundred dollars up front, which would cover all of his office visits for the year. We had agreed to that and did visits for his food allergies (which really just involved us making the food, bringing it, and having him eat it there to make sure he didn't have any reaction). First, each visit took at least 2 hours because there was always a long wait before and during the appointment. Then, months later, we started receiving bill after bill from our insurance, which they had billed even though we agreed not to go through insurance, and the bills were for hundreds of dollars for every single visit. In addition to being billed for the office visits, we were also billed for injections at most of the visits although my kid has never had any injections there. We have tried for months to resolve this with the office and their billing department and 1) it takes multiple calls just to get someone on the line and 2) each person tells us something different and inconsistent. We were first told for months that the bills were errors and would be rectified the following month (which is why we continued our visits) but the billed amounts became more and more egregious and then we were told no such policy of paying an amount up front exists, which is incredulous because we were definitely charged hundreds up front and if there is no policy, not sure why I would just offer to pay them hundreds on my credit card and why they would have accepted and made that charge on my card. This office can't be trusted at all for their fraudulent billing practices, which other reviewers had mentioned as well. I wish I had seen the reviews prior to seeking care there and hadn't trusted them. read more

Dr. Marks-Cogan and her entire staff of medical assistants have been great! Very friendly, knowledgeable and good at explaining things to help me understand. I'm undergoing the allergy immunotherapy treatment and when I had an unexpected delayed reaction at home, she immediately got on a video call with me and stayed on after hours to walk me through what to do. It was really above and beyond care. read more

Doctor Katie Cogan is a great caring Doctor . On every visit she takes time to explain my needs and very helpful with her recommendation . Thank you for being so kind and caring . Mike Manafian . read more

I wish Dr. Marks and her team could run my entire life. She takes the time to customize treatments and find fixes for my severe allergy issues, and it truly means a lot to be listened to and cared for. Her team - Ally, Michelle, Jeanie, and Sofia - are all patient and professional. I was coming in once a week for two years and was treated well every single time. I'll also gently mention on the bait and switch charges a few others report below - call your insurance. I've had severe allergies for many years, and when I get an unexpected bill, it's (without fail) an issue with my insurance policy changing or an incorrect billing code applied by the insurance company - it's never been Dr. Marks or her team. Dr. Marks is great and I can't recommend her enough. read more

For over a month, they have been injecting me with the incorrect allergy shot. I have experienced major setbacks in my allergy shot progress and now have to start all over, along with an unexpected rise in allergies this week as a result. read more

While my actual visit at Clear Allergy was fine, enjoyable even... their billing practices are ridiculous. It's such a bait & switch, and I'm extremely frustrated at the piss poor service I've received following my visit. After paying the initial co-pay and authorizing a $250 hold on my card, for what was supposed to be the maximum amount I'd have to pay if my insurance didn't kick in, I received another bill in the mail. Do not tell your clients that the price for your service is going to be X, and then hit them with additional fees a month later! I called and spoke to their billing office, where some condescending woman kept talking over me and trying to explain to me how deductibles work... Lady, I know how deductibles work. Tricking people into getting a service that costs more than the advertised price is super frustrating and is only going to lead to more dissatisfied clients. read more

We discovered our 20-month old daughter had a food allergy through a scary episode over the Thanksgiving holiday weekend. Dr. Marks-Cogan was highly responsive and very helpful in navigating us through what to do as well as what to expect over the next few days. She quickly brought us into her office the following week to do a follow-up and confirm/test for any other related allergies as well as train us parents on how to handle any future events. Because she is a mother herself, she knew exactly how to handle our daughter and make her feel safe during what could have been an overwhelming visit. We feel very indebted to Dr. Marks-Cogan and are so thankful to have her in our lives! read more

She is one of the best physicians around - thorough, kind and caring. I think myself lucky to have been referred here. You will be too!!! Top notch read more

My family has had an amazing experience with Dr. Katie Marks-Cogan and her office at Clear Allergy. When our daughter had a pretty severe skin irritation and vomiting to something that seemed like an allergic reaction we reached out to Dr. Marks-Cogan. She responded immediately and set up a time for us to come in right away. It is obvious that she is so knowledgeable and very quickly honed in on the potential issues which she discovered after a quick test were two nuts. You can really tell that she cares for her patients and made us feel very comfortable that we would be able to handle this and that our daughter was going to be ok after such a scary experience. We can't highly recommend Dr. Marks-Cogan enough as she has taken the best care of our family in every possible way. read more

De. Marks-Cogan is kind, thorough, incredibly smart, and just a phenomenal doctor. I have a high deductible plan and felt their billing practices were fair and straightforward. It was to know what I would owe before anything happened. Drove all the way from Orange County and could not be happier. read more

Follow up because I am so happy! It's been 3 months since our appointment and my daughter is now drinking 2.5 ounces of COW's milk each day because of Dr. Marks Cogan guidance!!!! (I was nervous because of my daughter's eczema and because her brother can't even go near milk!) Thank you! read more

I do not recommend this clinic. I went here for a simple skin allergy test, which took about 20 minutes. Prior to the appointment I was given a very specific price. A month later, I received a bill for double that amount with no explanation on the increase. I have tried to contact their office multiple time with no resolve. read more

Dr. Katie is exceptional with both of my kids. My 4 year old had an egg allergy and she was so amazing with him that he never minded getting allergy tested with her. She was so much fun he wanted to go! And my infant had eczema and she was on top of him too and so diligent in creating a plan for us to make sure we treated him properly. Dr. Katie is so knowledgeable and on top of the latest research, we feel so lucky to have found her! read more

I just moved to LA last year and have never experienced such bad irritation in my eyes and skin until recently. My main doctor referred me to Dr. Marks-Cogan and said it may be allergies and sure enough Dr. Marks-Cogan was able to show me that I have some serious allergies that have popped up in my life. My experience was pretty great. When I called I was able to get an appointment the next day and at my visit, there was no wait time and the staff wasn't like those at typical clinics who are usually disinterested and emotionless. I definitely did not expect the test to cause me to be so itchy, but an MA (Deena or Dina) gave me some itching cream when I complained and it went away pretty quickly. Appointment wasn't so long either so that's a plus. Highly highly recommend. read more

Dr. Katie was amazing! She answered all of my questions and was very thorough. I love when a doctor spends time listening and actively engaging to help better understand your health concerns and previous issues. She also helped me build a good action plan to manage my allergies moving forward. office staff was also friendly and made it easy to set an appointment. read more

Dr Marks-Cogan has been an incredibly knowledgeable and compassionate allergist to us for years now. She really cares about doing what's best for patients and takes the time to explain what she's doing. I'd highly recommend her for both kids and adults! read more

Such an amazing doctor, great bedside manner who I felt actually listened to my concerns. Definitely will be coming back!

Dr. Marks-Cogan is amazing. She really cares about her patients and doing everything she can to help them. She's a fantastic doctor who combines expertise with a great bed-side manner. read more

I just want to start off by saying I have never been to an allergist before. I was referred by my friend who told me this office was opening up near me, and I was curious to see what I was allergic to. I can tell you that right off the bat that their staff is extremely considerate and try to accommodate their patients. I wanted to get an appointment before I went out of town for a few weeks and they were able to fit me in the next day. Shea was so friendly and booked me within a 5 minute phone call. One thing that I will say is that I was a bit uneasy since I really wanted to do allergy testing but they couldn't guarantee it. But it worked out because Dr. Marks fit me in to do testing during the same appointment which was pretty helpful for my schedule. Overall, great experience. Wasn't allergic to much but it was neat to know. read more

For about the past two years, my throat always itches every time I eat onions and as someone who sings, it is irritating. I was referred to clear allergy, and it was the first time I have ever seen an allergy specialist. The staff was caring, and the medical assistant Dina was able to take down symptoms and calm me by explaining how my allergy skin testing would be as I was confused. Normally, I feel awkward speaking to medical staff, but I did not feel intimidated at all, and Dr. Marks-Cogan nicely explained my results. Turns out I am allergic to a few foods, and will probably come back for environmental testing per curiosity. The office was cool too! read more

Dr. Marks was incredible when we had a peanut allergy scare with my baby son. She encouraged us to continue safely introducing peanut butter to our baby, and assured us that many babies have sensitivities that should not be mistaken as allergies. I put my trust in Dr. Marks, and she is an incredible asset to us on the west side. read more

I brought my son to Dr. Marks-Cogan after his eye swelled up after a play date. It was our first time seeing an allergist and I didn't know quite what to expect. Dr. Marks-Cogan ran a few allergy panels and determined quickly what the problem was. Dr. Marks-Cogan is 100% current on allergy care and her office is spotless and her staff is incredibly efficient. read more

If you're looking for an experienced, personable allergist, look no further than Dr. Katie Marks-Cogan. She's clearly an expert in her field and offers thoughtful medical advice. Even better, her warmth and personality makes her an ideal physician for patients of all ages. If you're dealing with allergies and are seeking the right medical professional in Southern California, there's no one better than Dr. Katie! read more

We LOVE Dr. Marks- Cogan! She is amazing and helped us so much with our son. He had eczema as an infant which she helped us with and then we saw her again for food allergies. She was so sweet and patient with him and created a plan for us. Her office staff was very kind and they were on time. Highly recommend her and her practice. read more

I have 9 small grand children, with parents who work long hours, so I often take my grandkids to their doctor appointments. Dr Katie is a treasure. She cares deeply about my grandkids and has helped them tremendously. My 4 year old grandson is no longer allergic to eggs, which is a huge milestone! Dr. Katie explains things thoroughly in a way that I can understand. Dr Katie and her wonderful staff are truly a blessing in my life. I only wish all my doctors were as compassionate as Dr Katie is. read more

Dr. Marks-Cogan is extremely kind and patient as well as being the best allergist we've seen. You can tell she sincerely cares about her patients. She took the time to really explain things as well as understand everything about possible allergens for my daughter. She was also wonderful with my 2-year old. Being a mother herself enabled her to have perspective that I appreciated. She keeps up with new medicine and alternative ways to treat and even prevent allergies. You and your children can't go wrong with her. read more

The people were not the problem at this place, but the financial transparency was! There were too many avenues for you to be overcharged and under-explained. It happened to a friend of mine as well! Bottom line, if you are unclear, you need to foot the bill - not the clients!!! read more

I can't recommend Dr Marks-Cogan enough! You can clearly tell that she cares about each and every one of her patients. Also, her level of knowledge and expertise in her field is evident through her thorough approach to everything. I feel so lucky that she practices in LA; she truly is an experienced and caring allergist. read more

Dr Marks-Cogan is a dedicated doctor who is kind, and compassionate and confident in the field of allergies. She took the time to help my daughter when were concerned about her allergies. She answered all my questions and reassured me that we would have some answers on the best way to manage her health needs. Dr Marks-Cogan was easily reachable when planning on sending my daughter to sleepaway camp for the first time and provided easy tips on how to deal with allergies in a new environment. She sent me links on what types of bedding to get and the proper medication regime. read more

Dr. Marks-Cogan is amazing! She helped my children through testing and treatments for environmental and food allergies. She is fun, patient, and connects well with children all while providing clear and useful feedback to adults. I especially appreciated that she provided us a variety of options and we worked together to select the treatment plan that worked the best for our family. I highly recommend Dr. Marks-Cogan. read more

We have been so lucky to have Dr. Marks-Cogan as an allergist! She brings medical expertise and practical guidance to any question. Our son has food allergies, eczema, and asthma, and she has helped us navigate all the changes with such great knowledge and compassion. Thank you! read more

We called Dr. Marks-Cogan in a panic after our daughter had an allergic reaction to eating peanut butter. She was able to see us right away and worked up a full allergy panel. We got the results quickly and Dr. Marks-Cogan was excellent in calming our fears and giving us tips for how to handle and live with such a severe allergy. She has a great bedside manner and is exceptionally knowledgeable. read more