Ummmm…. I'm not sure what formulation that they're on (whether it's Atripla, or otherwise separate), but I must forewarn you that Efavirenz should be avoided like the plague. It's more commonly known as Sustiva, and while your friend may not realize it now, but Sustiva is a very evil drug. I have seen first hand the kind of damage that Sustiva (Efavirenz) can do to a person with long-term use. For example, thanks to Sustiva, my ex now suffers from a severe case of peripheral neuropathy. To go along with this, he still frequently suffers from brain farts as I like to call them where he'll mean to say one thing, but will reverse the order of a few words, or otherwise associate the wrong word with something, leaving the person that he's talking to very confused.
I would strongly recommend that your friend get off of Sustiva ASAP for their own good. I'm not saying this to be a bitch or anything, but rather out of serious concern because I have seen first hand what Sustiva will do to a person with long-term use. I would be more inclined to recommend the switch to something like Truvada (Tenofovir 300mg / Emtricitabine 200mg) & Isentress (Raltegravir 400mg) as a substitute in the meantime. There are two down sides to this regime, however they're more manageable when paired up with something like Lomotil. The first down side is that Truvada often causes dry mouth and (and I say this from first hand experience of having been on it myself) can make for a rather "shitty" situation, if you catch my drift. The other down side is that Isentress in its standalone formation needs to be taken twice a day, which is statistically proven to be harder to adhere to than a once a day treatment.
Once on that regime, I would be inclined to recommend that they get a blood test done known as the HLA-B5701, which tests to see if you will have a rather serious reaction to Abacavir. If this test comes back negative, I would be inclined to recommend at that point making another switch from the Truvada/Isentress combination over to Triumeq. It falls under the same drug class as Isentress, however is formulated differently as to only need to be taken once a day. This would roll them down into one pill once a day. That being said though, I would not recommend just starting the Triumeq blindly as the reaction that the HLA-B5701 tests for is a severe body rash that can blister and become quite painful. To my understanding, it is the most common side effect and is thought on the most part to be the only real known side effect. I have been on this regime now for a while and have noticed no side effects to speak of. Also, on that note, it just so happens that the class of drugs that the Isentress falls into happens to now be regarded as the most powerful class of medications when combatting HIV in the world. It is responsible for me finally breaking the 700 mark in my CD4 count and coming in at an all time high of 1040 as of the last test.
Triumeq is a combination drug that mixes Dolutegravir, Abacavir, & Lamivudine, however it is rolled down into one pill. It's similar to a solution such as Atripla (which more or less is Tenofovir & Emtricitabine (or Truvada) and Sustiva (Efavirenz) all rolled into one pill), only it uses the newer medications and is all rolled into one pill that is taken once daily. In all seriousness though, I strongly recommend the discontinuation of Sustiva ASAP for their own good. If they're comfortable staying on the Sustiva for 3 months or so for the HLA-B*5701 test to come back, it may make more sense to make the switch over to Triumeq right off the top. It's proven to be much more effective, without the hassles of the nasty side effects. I know this may sound like I'm out to lunch, but this is something that I happen to have years of first hand experience with. I would not recommend making such a switch if I did not feel so strongly against the use of Sustiva. It's seriously saddening to see what 13 years of Sustiva has done to my ex, and I seriously would not wish that kind of life on anyone.
Again, understand that this is my opinion based on the years of experience that I have first hand with these medications. I seriously think that they would be much better off with one of the newer options such as Triumeq because it's easier to manage, without the hassles of the side effects. I know that they're happy enough dealing with the side effects for now, but I can say first hand from my own experience that there WILL come a time where the side effects will eventually become quite depressing, which can cause a number of other issues. What I'm getting at here is why deal with the side effects if there is an alternative that is clinically proven to be more effective that will help them manage, without the side effects? In all seriousness I'm not trying to criticize their decision to stick with it. My only intent is to offer my experience to try to help by providing a better solution that is easier to manage both physically and for long-term mental & physical health.
All this being said, Triumeq is rather new, so it's possible that at the time that their doctor put them on the Sustiva option, the option of using Triumeq may not have existed at that time. It only came out within the last about 4 months or so, so I would imagine that this is likely the reason why their doctor hasn't yet recommended it.