Hello doctor, After 21 months since my HIV diagnosis and have been undetectable for 15 of those months, two months back I was switched from the effective Truvada or Tivicay regimen to Triumeq. The sole explanation was that STR was more convenient. I am yet to do labs with Triumeq, but I have three concerns at this point: 1. Was there any possibility of a viral rebound or a significant blip, 5 to 6 weeks into Triumeq use, due to a new combination of drugs? (I have 100 % adherence and take medicines always at the same time, +/- 2 hours) 2. Due to some intensive driving trips, on a few days in the last two months while already on Triumeq, I had a can or two of energy drink shortly (certainly less than two hours) after taking my medicines and without realizing it contained some magnesium (about 7 mg per can). Is this a significant enough amount to interfere with DTG absorption and thus efficacy? (The Triumeq guide instructs avoiding calcium or magnesium-containing antacids, but their quantities usually are much higher. In my case, this was less than in a medium size banana fruit). 3. While maintaining my UD status, how risky to my negative partner was the following episode during a sexual intercourse with me being in the receptive role? He briefly inserted his penis rather deep into my rectum without condom and instantly had a tear at the top of the penis where it connects with foreskin. He pulled out right away, but his wound was already bleeding rather profusely. Was he at high risk of HIV infection, despite my UD status?
Hi. 1. It is not at all advised to substitute regimen with another drug on your own choice based on convenience. The reason is group resistance. The substitute you made are used in vice versa condition, that is used in case of failure to switch to second-line medication. 2. Dolutegravir has interaction with antacids which contain calcium and magnesium salts and these interfere with absorption, but nothing harm in occasional use, as drug remains above therapeutic levels for more than 5 to 7 days.  3. Anal activity has a significantly high risk, as there will be no active defense cells and there is increased chances of mucosal tears which increases chances of HIV transmission. So, he is at risk of transmission.