Question
How quickly does viral load drop on treatment?
5 July 2020. Related: All topics, CD4 and viral load, Starting treatment.
I’ve been trying to understand on average, the daily rate of decrease in viral load following initial treatment.
I’m guessing that this changes over time and varies from case to case according to the chosen treatment, CD4 count and viral load level and possibly other factors.
However, supposing that the viral load is around 100,000, the CD4 count is around 400 and the treatment used is Atripla, could anyone please let me know the expected % decrease of viral load level per day at least within the 1st month of treatment?
Thank you for the help.
Answer
All HIV combinations (ART) starts working from the first dose.
Viral load is usually reduced by 90% (also referred to as 1 log) within the first few days. It then continues to fall but not as quickly (see below) until it becomes undetectable.
A log is a number mulitplied to the power of 10. So with a viral load of 100,000 copies/mL, a 1-log reduction would bring your viral load down to 10,000 copies/mL and a 3-log reduction would reduce it to 100 copies/mL. (See this factsheet).
You are right that individual factors will lead to difference rates of viral load reductions. These include:
- How high your viral load was when you start ART.
- The medicines in the combination (integrase inhibitors casuing the fastest drops).
- The drug levels of this meds (related to adherence and how they absorb and processes drugs).
- Good adherence – not missing doses.
UK and US guidelines recommend that your viral load should be undetectable within three months. However, many people achieve this within the first month, especailly if they are using an integrase inhibitor.
Some people take longer, especially if their viral load is very high when they start treatment.
Lots of studies have reported detailed early responses ART, including for efavirenz-based combinations like Atripla.
This decline is often referred to as having three main phases.
The first phase is very rapid – referred to in some studies as being the first few days and in others as within the first two weeks. This is where the actively infected CD4 cells are targeted. CD4 cells infected with HIV only live for a few days and when you start treatment this virus and these cells are quickly reduced.
This results in a viral load drop of perhaps 99% (2 logs) within two weeks.
The second phase, out to the first month is slower, as it is working on cells that live longer. This can easily reduce viral by another 90% (another 1 log reduction). In people with very high viral loads when they start treatment, this second phase may continue for longer until viral load becomes undetectable.
Some researchers also talk about a third phase decline which occurs even more slowly and gradually once your viral load is undetectable.
This relates to a reduction in the levels of infected CD4 cells that are latent (or resting). This pool of cells only slowly decreases over time.
This link is to an early study describing the two-phase viral load reductions.
This answer was updated in July 2020 from a question first posted on 15 September 2012.
Hi im so stressed im waiting for my viral load result this month it was too high and doctor change me to regimen two but i feel strong and looks healthy in my body and gaining weight is my decreased pls answer me im so stressed
Hi Kevin,
From your results, its safe to say that you’re doing really well. Amazing in fact. Not having any side effects is a real bonus.What your friend’s said is wrong. When someone begins meds their viral load should drop like this, and this fast. Your CD4 is also doing really well. With time this should rise either further.
With regards the kidney issue, what exactly’s happened? What meds are you on?
I have a quick question about viral load / CD4.
I was diagnosed on June 21, 2018 this year with a viral load of 63,000 and a CD4 of 197. I quickly started meds and did labs in 20 days. The results are as follows: CD4 – 304 and viral load 777.
I was under the impression that the viral load would decrease rapidly but was also under the assumption that the CD4 would drop but instead it increase – i’m happy to be above the 200 marker as this is all new and trying to understand everything. Only problem is that the meds and the kidneys are not working well together so im getting more blood drawn to tweak the medication. I have had no side effects whatsoever.
Is this typical the first x months to tweak medication blood tests to find whats right – my friend who i have been confiding in says that the results are not realistic because the viral load went down so fast.
Just want to make sure i’m doing everything right and get a grasp of what happens next etc. since this is all new!
Is there anything i need to do or ask my physician to look at?
Hi Spha,
I think you’re question is about meds not working if they are not taken in the right way. Yes, that sounds right. But it looks good that your viral load is coming down now that you’re taking the meds on time and in the right way.
You can read about some tips for adherence with your regimen 2 here.
Have you got a weekly pill box? Many people say this can really help. You can see if you miss a dose with one of these. You can ask at your clinic. They might provide one for you.
Hi I started my HIV treatment in June 2016 , well because of side effect i couldn’t keep adherents to my meds . Then I went for my first viral load check up it came back 13000 i then given a second chance then the result came back 29000 then it kept on going up till it was 375000 the doctor told me to try one last time now with taking my meds correctly without giving excuses all the time then was given a two months treatment before my last vial load check up I did exactly as she said luckily my viral went all down 375,000 to 46,600 was then given another two months treatment den it went down to 29,000 the doctor decided to change my treatment to regimen 2 but my question is the first treatment wasn’t working for ? But coming from 375,000 to 29,000 after now taking my meds religiously , because before wasn’t taking my meds as was supposed to.
Hi Micheal,
Has your CD4 count gone up? A CD4 count of 7 means that you can need antibiotics and other meds for other infections. Did the doctor give you these meds too?
Your viral load will drop quickly once you start HIV treatment (ART), as it says above. Was your viral load very high before you started ART? This can mean that it’s taking longer to get to undetectable. But you can ask the doctor to test for drug resistance. And if the meds are not working you can ask to switch to different meds.
However, it’s important to talk to the doctor about your latest CD4 count to see if it has gone up.
when I was dianosed with HIV in Feb I was told that my cd4 is on 7 I could not do anything without being exhausted and in pain I started treatment in March the 27th until now 26 June they tell me that my viral load is on 302000 copies/ml was I supposed to be started on regiment 2 or what can I do to lower this because I take my treatment on a daily basis but the blood results say otherwise? am I resistant to the treatment?
Hi Trylantia,
Are you taking HIV treatment (ART)? What meds are they and when did you start? Here’s a picture that shows what happens to viral load and CD4 count when you start ART.
im stressed my viral load is high what can i do?
Hi Caroline,
It’s great that your viral load is undetectable. And a CD4 count of 700 is strong. But it’s important that you continue to take ARVs to stop HIV from bouncing back. You can see from this picture that once you start treatment with ARVs (ART) your viral load drops dramatically. But for most people ART needs to be taken daily to keep HIV at these very low levels.