|2 Missed PREP Truvada doses
Jul 13, 2014
Thank you for reviewing these questions! I have reviewed this forum for years -- has been a life saver.
I have two questions.
Background: I have been on PREP for 4 months without ever missing a dose. My last exposure with any degree of risk has been approximately two weeks before the situation I am describing.
This last weekend, when traveling, I forgot my bag and was on an odd schedule. I was unable to take two of my Truvada PREP doses two days in a row.
If I do not miss any more doses for the month, assuming I have been exposed to HIV, is my risk much higher?
I understand the efficacy of PREP decreases with missed doses, but the studies show much more risk if a 1 or more doses are missed WEEKLY. If I already had therapeutic levels in my blood, I imagine that I was not without the drugs in my blood for very long -- less than the period of time people are typically started on post exposure prophylaxis. And if I do not miss any more doses, then I will not have regularly missed doses and I am not sure how the studies will apply to me.
THANK YOU! FIRST TIME POSTING AND SO GRATEFUL!
| Response from Dr. Young
Hello and thanks for posting.
There's not much specific data on how missed doses affect PrEP effectiveness, but we know that HIV treatment requires adherence around 90% or greater for optimal response. Missing one dose per week calculates out at 26/30 or 87%- probably lower than ideal. Missing more than 1 dose/week only increases these risks.
What's probably more important is the relationship of the missed dose to any possible HIV exposure. The effect of the missed dose would likely be greatest if it occurred in the 24-48 hours prior to, or after the exposure.
Perhaps a pill box or other reminder system can help you with your adherence-- or, in the future, a once-monthly PrEP injection.
Hope that's helpful, BY
Get Email Notifications When This Forum Updates or Subscribe With RSS
- What If I Miss A Dose Of Truvada?
- Flu Symptoms After Unprotected Oral Sex Without Ejaculation Worried I Have HIV
- Itchy Skin After Precum Touching Vagina Sign Of HIV AIDS
- Tingling Lips After Anal Sex Top Sign Of HIV AIDS
- White Bumps On Penis After Oral Sex Form Sex Worker What Are The Chances Of HIV
- How Long Does It Take To Detect Std?
This forum is designed for educational purposes only, and experts are not rendering medical, mental health, legal or other professional advice or services. If you have or suspect you may have a medical, mental health, legal or other problem that requires advice, consult your own caregiver, attorney or other qualified professional.
Experts appearing on this page are independent and are solely responsible for editing and fact-checking their material. Neither TheBody.com nor any advertiser is the publisher or speaker of posted visitors' questions or the experts' material.