Is Taking PEP Riskier than Chance of HIV Transmission?

[NothingFancy]

Hello! Can you please help me decide if I should take Post Exposure Prophylaxis: Truvada 200 mg (emtricitabine-tenofovir) plus Tivicay 50 mg (dolutegravir) for 28 days to reduce likelihood of HIV illnesses. These meds have potentially serious side-effects. Perhaps taking the meds is more dangerous than doing nothing in the following circumstance?

I'm a fairly healthy circumcised male in my 60s. I had unprotected vaginal sex with a busy commercial sex worker for one hour on two occasions. Assuming she has an HIV infection - it seems my chance of infection is about 0.10% to 0.05% per encounter - i.e. 0.20% risk for two unprotected encounters... (% per Wikipedia STDs chart - BTW I am dealing with other potential STIs separately tomorrow). The unprotected sessions also included fellatio, cunnilingus and mutual analingus.

The Rx came from an RN at a clinic visit 8 hours ago; I see my primary care physician in 12 hours.

I appreciate all input!  Thank you.

[mike_no]

Looks like you've got it all sorted. The chances of you acquiring infection from your event was astronomically low. 2 very important factors driving my statement. One, CSWs are very careful about their own health, due to the education they receive about STIs. I am amazed, how did this person agree to unprotected intercourse at the first place?!

Two, exactly what CurfewX stated, FTM transmission ratio through unprotected vaginal exposure is low and difficult. Other activities that you described are not risk for transmission.

I am sure you must have been briefed by your doctor, the earliest you can take a test is after 28 days from the last dose of your PEP.

Come back to post your negative. Use a condom the next time.

Good luck.

[NothingFancy]

Thank you m_n.
I'm on Day 3 of 28 PEP. I started these scary meds per advice of two medical practices 70 hours after last exposure.
8 hours later I had cold symptoms - endless runny nose, sneezing, runny eyes - but this might just be a cold.
I'm unsure how HIV Screen 4th Generation results from blood drawn 60 hours post exposure will change my treatment. If positive maybe I will be told to continue Truvada and drop Tivicay (i.e. cease PEP and start HIV treatment.) I'm still unsure I should be risking side effects for a 0.4% probability I'd get HIV even if my partner was infected.  Anyway - one day at a time!  BTW a lot of mid-tier CSWs bareback - and say they know what they are doing to stay healthy!?! I assume they risk the diseases and go on vacation when they get something. Cheers! (sorta)

[CurfewX]

Also, I don't know when these encounters occurred, but PEP is only  effective when taken within 72 hours of the event.

[NothingFancy]

CX thanks for info and personal opinion. I was leaning toward No PEP based on low transmission statistic that nobody disputed.
Now I plan to start PEP meds tonight.  

TL;DR follows. Hope it may help somebody.

I was pleased the minute clinic NP called. She listened to my thoughts and pointed out getting blood today was important.

I was amazed Truvada had zero co-pay with a $2144 list price. Tivicay $30 co-pay, list $2196. I have the best insurance ever for meds, labs and doctors.

Fortunately my primary care practice fit me in and listened to my situation. I wanted opinion of NP's plan - and PEP side effects vs my various meds and health history. My MD & PA separately reviewed minute clinic NP's prescriptions. I said I as scared of side effects as HIV. They said they had other patients on these or similar meds successfully.  

Both suggested I start meds today as no immediate side effects were likely.  If tolerated, continue meds for 28 days. But call immediately if any STD symptoms or side effects occur.

Phlebotomist drew blood samples: HIV Screen 4th Generation, every big-name STI, Hepatitis B & C, Comprehensive metabolic panel for High Risk Sexual Behavior. Some results take 7 business days; others sooner. If lab reports anything significant, they call me ASAP.

The 72-hour deadline to start PEP meds is 11:30 PM 1/7/20 tonight. I'm told PEP likely works if I was indeed infected.

Complication - my 1st unsafe intercourse actually occurred on 11/17/19 - a condom broke and went undetected for twenty minutes. If I was infected 11/17, chance of PEP working is nil.  I asked if 11/17 incident disqualified me per PEP 72 hour window rule.  Nope. They said 'Nothing to do about that now' - except await tests.

I had a text conversation with my partner. She says she knows she doesn't have HIV; and takes care of her health mindful of 'her business'.  While I hope she is truthful, I am not basing any decision on her answer.  Her behavior is very high risk.

(BTW: Her 'no HIV' statement is technically disqualifies me: 'no PEP treatment absent HIV-positive information'. But the medical team understood I couldn't get a copy of her test results or date.

I have the meds in hand, ready to start tonight.

[CurfewX]

PEP is generally only recommended for people who have had a known exposure to HIV - unprotected intercourse with someone who is confirmed to be HIV-positive.  Personally, I would not take PEP for a one- or two-time encounter with someone not confirmed to be HIV+, but that is a decision only you can make.  PEP does have some side effects, but most of them go away after the conclusion of the course of treatment.

Only the unprotected intercourse was a risk - the other activities aren't a risk for HIV.