psoriasis, Psoriasis Treatments

3 Weeks with Tremfya: The Waiting Game

The beach at Point Montara Lighthouse (south of San Francisco) proved a wonderful and peaceful spot to spend Labor Day Sunday and Monday with a church group.

Are we there yet? It’s a question every parent has heard asked by a child in a long line or road trip. After three weeks on Tremfya (Guselkumab) I know I shouldn’t be asking the question, but I’m anxious to know when I might find clearer skin. It’s a waiting game that I feel like I’m losing.

I don’t have exact data on when people’s psoriasis started responding to Tremfya. During Phase II trials one paper mentioned patients saw response by the four week check-up. But my dermatologist agrees with the charts I’ve seen where many people respond after the second injection at week 4.

When Will Tremfya Start Working?

In my quest to understand more about how long I might need to wait, I began reading about medication half-life, loading doses, and steady-state concentrations. I seriously want to talk to a pharmacist or a doctor who can explain pharmacokinetics to me. Or I need the pharmacokinetics for dummies book if one’s available.

What I gathered is that it takes 5-7 half-lives for a medication to build up to the desired concentration (steady-state) in the body. I always thought of half-life in terms of degradation, i.e., the time it takes for something to degrade by half (then another half from there). You know, as in carbon or radioactive dating, But apparently there is also a half-life for the concentration of a medication to build up in the body.


What I gathered is that it takes 5-7 half-lives for a medication to build up to the desired concentration (steady-state) in the body.


Tremfya’s mean half-life is 15-18 days. With taking the average of the mean (okay I’m just going to use 16.5 days for the sake of argument) 5-7 half-lives would be about 83 (12 weeks) to 116 days (16.5 weeks). The extra dose at week 4 adds another factor I’m not sure how to calculate, but speeds up the process. Another factor, I’m reminded by my pharmacist today, is the time it takes the medication to calm the inflammation on my skin even after reaching steady-state levels in my body.

So, when the charts show the majority of people’s psoriasis responding between 4 and 12 weeks, that matches with my super rudimentary, untrained calculations and what clinical trials show.

I wish today were week 4 (upcoming Monday) so I could take that second injection. Unfortunately, I’m just a couple days past week 3. Are we there yet?


Follow my Tremfya journey

Tremfya (Guselkumab) Week One

5 Weeks with Tremfya: Biggest Fear?

6 Weeks with Tremfya: Redefining Expectations

8 Weeks with Tremfya: It’s Working!

10 Weeks with Tremfya: One Step Back

12 Weeks with Tremfya: The Third Injection

14 Weeks with Tremfya: What’s Next?

16 Weeks with Tremfya: The Verdict?

20 Weeks with Tremfya: Read the Instructions! (4th Injection)

24 Weeks with Tremfya: A Pattern Emerges

28 Weeks with Tremfya: Still Working? (Injection #5)

38 Weeks with Tremfya: The Question/Answer Edition

42 Weeks with Tremfya: Coping with a Skin Flare


Two Weeks with Tremfya on Labor Day

I marked two weeks on Tremfya on Labor Day last Monday. The second week on the new medication felt uneventful psoriasis wise. I thought I started seeing some response to the medication on my stomach and back about ten days into the treatment, but those spots returned a few days later. At the same time, my forearms and lower legs do look more clear of psoriasis.

A few more psoriasis spots popped during the third week as well. But I stopped Enbrel (etanercept) over three weeks ago. It’s possible I’m experiencing a psoriasis rebound from discontinuing Enbrel and lowering my cyclosporine dose.

While I can’t say for certain that Tremfya caused me to feel tired or ill, the second week I continued to feel tired and ill. I slept more than normal. I took asthma rescue puffs into my lungs more than usual. Periodic headaches came and went like the tide. But by the Labor Day weekend I started feeling better. I wonder if those symptoms will return after taking the week 4 dose?

During the third week I started running and walking regularly again despite the California Central Valley heat and periodic smoky air due to wild fires. I love running, and knowing I’m doing something positively good for my health motivates me to keep going in under less than ideal environments.

The Stress Factor

Another reason I might still be waiting for my psoriasis to respond to Tremfya is added stress. That second week I went to meetings or gatherings five out of seven nights. I also scrambled to meet a couple blog deadlines, one of which I ended up missing. I don’t miss deadlines, so when I do I feel behind and STRESSED.

That second week marked the end or psoriasis awareness/action month. To commemorate the month I took the opportunity to speak at a biotechnology company in the Bay Area called Dermira. They asked me to share my psoriasis journey with them during their lunch time staff meeting. A lot more people packed the room than I imagined would attend. That day we drove five hours and spent two hours at the company. Awesome day, but stressful and tiring.


Therefore do not worry about tomorrow, for tomorrow will worry about itself. Each day has enough trouble of its own.


My skin gave me the angry looks of red, irritated lesions that emerge during stressful times.

The Guessing Continues

The waiting game is also a guessing game. This blog confirms that I think about what’s happening with psoriasis ALL THE TIME. I try to read the skin “tea leaves,” but only God truly knows what’s going on with my complex immune system. Only he knows what’s going to happen at week 4 and beyond.

I’m reminded of what Jesus said as he taught his followers: Therefore do not worry about tomorrow, for tomorrow will worry about itself. Each day has enough trouble of its own. (Matthew 6:34). I have lots to manage today, so I better get to it. Staying in the moment helps me pass the time anyhow while waitng for those half-lives.


5 thoughts on “3 Weeks with Tremfya: The Waiting Game

  1. Pingback: The Waiting is the Hardest Part: A Reflection on Psoriasis Treatments – PsoHoward

  2. Isabelle Estrada says:

    Thank you for the updates and encouraging words. My son started treatment with a pill for psoriasis creams not working Pill seemed working at first but some read spots has returned. Tomorrow morning we go to the dermatologist for follow up. She stated it takes time to clear but also his joint pains as increase as well. I am praying that God will heal him and use the right medication to clear him up and specially getting free of joint pain.

    Liked by 1 person

    • Hi Isabelle, thanks for reading! I pray the appointment with the dermatologist provided a way forward especially with the joint pain. Has he seen a rheumatologist (they specialize in treating the joints and psoriatic arthritis)?

      May God’s grace be upon him each day with healing and power.



      • Isabelle Estrada says:

        Hi Howard,
        Thank you for response. The appointment went somehow ok..the dermatologist wants to start another treatment plan Enbrel. We are a little concern about the shots due all the other things that we are reading can cause and to be honest scary. My husband is already thinking in getting to a second opinion. For my son’s joint pain, no we have not seen a RA, doctor. according to the results for RA, it came negative so, dermatologist stated it takes a while for the treatment to kick in for the joint pain. Is my understanding that Enbrel helps to clear faster the skin and helps with joint pain . Very frustrated at this point, but hoping for a complete miracle from the Lord, He answers our prayers.
        Thanks Howard.

        Liked by 1 person

      • Praying for God’s timing and will in your son’s treatment. It can be difficult and take a lot of patience to find the right treatment. I used Enbrel for about ten years or so. If you want to chat more specifically about it feel free to email me at God bless you, your son, and family!



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