emtricitabine at a glance
Medicine class
Nucleoside reverse-transcriptase inhibitor (NRTI).
Licensed role
Combination treatment of HIV-1 in adults and children aged 4 months and over.
Food
Capsules and oral solution can be taken with or without food.
Available forms
Hard capsules and oral solution; they are not interchangeable amount-for-amount.
What is emtricitabine used for?
Single-ingredient emtricitabine has one main licensed use. It also appears in combination products used for HIV prevention.
Treatment of HIV-1 with other antiretrovirals in adults and children aged 4 months and over.
Emtricitabine with tenofovir is used for HIV pre-exposure prophylaxis (PrEP), but the selected single-ingredient products are not licensed for prevention.
Emtricitabine-containing combinations may form part of specialist post-exposure prophylaxis; this is not a licensed use of the selected single-ingredient products.
How does emtricitabine work?
Cells convert emtricitabine into an active triphosphate. This competes with a natural DNA building block at HIV reverse transcriptase and terminates the growing viral DNA chain, limiting replication. M184V or M184I mutations commonly cause resistance and cross-resistance to lamivudine.
emtricitabine preparations and strengths
Capsule
Route: Oral
Strengths: 200 mg
Oral solution
Route: Oral
Strengths: 10 mg/mL
How to take emtricitabine
Follow the dispensing label and take emtricitabine as part of the complete antiretroviral combination prescribed. It may be taken with or without food.
Swallow the hard capsule with water; tell your clinic if swallowing is difficult.
Measure oral solution with the supplied measuring cup, not a household spoon.
Do not switch between capsules and solution without prescriber or pharmacist guidance because their bioavailability differs.
Do not stop treatment independently, particularly if you also have hepatitis B.
emtricitabine side effects
Common or expected effects
- Headache
- Diarrhoea or nausea
- Dizziness, weakness or pain
- Vomiting, abdominal discomfort or indigestion
- Difficulty sleeping or abnormal dreams
- Rash, itching or mild increased skin pigmentation
- Muscle pain or weakness associated with raised creatine kinase
- Changes in white-cell count, liver enzymes, blood glucose or triglycerides
Get urgent medical advice
- Swelling of the face, lips, tongue or throat, particularly with breathing difficulty
- Severe or blistering rash
- A potentially severe hepatitis flare after stopping treatment in someone with hepatitis B
- New or worsening inflammatory symptoms after starting combination antiretroviral therapy
emtricitabine in pregnancy
Available data have not identified an increased risk of malformations or fetal or newborn toxicity, and emtricitabine may be considered when needed. Do not stop HIV treatment or prevention without specialist advice; the complete combination should be reviewed.
emtricitabine while breastfeeding
Emtricitabine enters breast milk. Product information advises against breastfeeding during treatment. NHS HIV information says formula feeding is safest, although supported breastfeeding may be possible with sustained viral suppression and specialist monitoring. For HIV-negative people using emtricitabine-containing PrEP, NHS guidance permits breastfeeding after clinical review. Discuss feeding plans with your specialist team.
emtricitabine interactions
Emtricitabine has little potential for CYP450-mediated interactions, but duplicate treatment and renal elimination are important.
Lamivudine
Do not combine routinely because it is closely related and has overlapping activity and resistance.
Other emtricitabine-containing products
Avoid duplicate therapy by checking every component of fixed-dose antiretroviral combinations.
Common questions about emtricitabine
Answers are fully visible for fast scanning and source review.
Can emtricitabine be used alone to treat HIV?
No. It must be combined with other antiretrovirals because single-medicine treatment is inadequate and promotes resistance.
Does emtricitabine cure HIV?
No. It limits HIV replication as part of combination therapy but does not remove the virus from the body.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.