On PrEP or On-Demand PrEP: What Is It? How Effective Against HIV in 2025

As sexual health becomes a growing priority, HIV prevention is no longer limited to condoms alone. Another globally recognized option is PrEP (Pre-Exposure Prophylaxis). When we say someone is On PrEP, it means they are actively and consistently using PrEP to maintain protective drug levels in the body.

In 2025, being On PrEP is more accessible than ever—not only for men who have sex with men, but also for women, heterosexual couples, adolescents, and serodiscordant partners. On PrEP is more than just taking medication; it is about protecting health and building confidence in every relationship.

On PrEP: What Is It and Why Are More People Choosing It in 2025?

On PrEP refers to the consistent use of PrEP (Pre-Exposure Prophylaxis) medication to maintain adequate drug levels in the body, providing protection against HIV before any possible exposure. The more consistently it is taken, the higher the effectiveness. According to global health authorities such as the CDC and WHO, daily use of PrEP can reduce the risk of HIV from sexual activity by over 90–99%.

In 2025, On PrEP has become increasingly popular as more people prioritize sexual health and peace of mind. Whether someone has regular or occasional partners, or engages in higher-risk behaviors, staying “on PrEP” offers a proven long-term option for HIV prevention supported by medical research.

How Is “On PrEP” Different from Just Saying PrEP?

The term PrEP refers to the use of medication to prevent HIV infection before exposure. When we say someone is On PrEP, it highlights that they are actively and consistently using PrEP in daily life—not just aware of it or planning to start.

Being “On PrEP” means:

• Regular health check-ups and HIV testing as recommended by a doctor
• Taking or receiving PrEP according to the prescribed regimen (Daily / On-Demand / Injectable)
• Maintaining consistency to ensure protective drug levels in the body

In short, PrEP = the prevention method in concept, while On PrEP = the actual, ongoing practice. This distinction is crucial for achieving effective HIV prevention.

Daily, On-Demand, or Injectable — Which On PrEP Method Fits You Best?

PrEP can be used in different ways, depending on individual lifestyle and risk patterns:

• Daily PrEP: Taken every day. Best for those with ongoing risk, such as multiple partners or inconsistent condom use.
• On-Demand PrEP (2+1+1): Taken only around the time of sex. Suitable for people with occasional risk, but it requires strict adherence to the dosing schedule.
• Injectable PrEP (Cabotegravir): An injection every two months. Ideal for those who find daily pills inconvenient and want consistent protection without worrying about missed doses.

The right choice depends on personal risk, convenience, and medical advice to ensure the most effective HIV prevention for each individual.

Who Should Consider Being On PrEP?

On PrEP is most suitable for people at higher risk of HIV infection in their daily lives or during certain periods. Groups that should consider it include:

• People who often have sex without condoms
• Those with multiple partners or whose partner’s HIV status is unknown
• Serodiscordant couples (one partner is HIV-positive, the other is negative)
• People who inject drugs and share needles
• Individuals who frequently rely on PEP after risky exposure

The decision to start On PrEP should be based on personal risk behavior and medical consultation to ensure it fits each individual’s needs.

On PrEP in Serodiscordant Relationships (When One Partner Has HIV)

A Serodiscordant Couple refers to a relationship where one partner is living with HIV and the other is HIV-negative. The main concern is the risk of HIV transmission during sexual activity.

On PrEP is a valuable option for these couples because it:

• Reduces the risk of HIV transmission by over 90–99% when used correctly
• Provides reassurance and strengthens intimacy by lowering anxiety
• Works best when combined with ART or ARV (antiretroviral therapy) for the HIV-positive partner, following the principle of Undetectable = Untransmittable (U=U)

Still, being On PrEP should be guided by a healthcare provider, with regular check-ups to ensure both safety and effectiveness for both partners.

On PrEP for Women and Heterosexual Couples

Although PrEP is often discussed in the context of men who have sex with men (MSM), women and heterosexual couples can also greatly benefit from being On PrEP, particularly in situations such as:

• Women with multiple partners or whose partner’s HIV status is unknown
• Women with partners in higher-risk groups, such as injection drug users or those who have condomless sex
• Heterosexual couples where one partner is HIV-positive and the other is HIV-negative (serodiscordant couple)
• Women living in areas with high HIV prevalence

For women and heterosexual couples, On PrEP should be prescribed and monitored by a healthcare professional, with regular health checks to ensure optimal protection.

On PrEP for Adolescents and Young Adults

According to international guidelines such as WHO and the CDC, adolescents aged 15 or older who weigh at least 35 kg may be eligible for PrEP if they are at risk of HIV. Expanding access to On PrEP in this group is important to reduce risk and promote sexual health from an early stage.

Situations where adolescents may be advised to consider On PrEP include:

• Having sex without condoms regularly
• Having multiple partners or partners with unknown HIV status
• A history of sexually transmitted infections (STIs) within the past 6 months
• Living in a community with high HIV prevalence

Adolescents should always receive medical assessment and follow-up, along with counseling on sexual health and mental well-being.

On PrEP During Pregnancy and Breastfeeding

The use of PrEP during pregnancy and breastfeeding has been studied and is supported by WHO guidelines, indicating that it can be used safely under medical supervision. The goal is to protect the mother from HIV and reduce the risk of transmission to the baby.

Situations where On PrEP may be considered include:

• Pregnant women with partners at high risk of HIV or who are HIV-positive
• Breastfeeding women who continue to engage in higher-risk behaviors, such as inconsistent condom use
• Women living in areas with a high prevalence of HIV

Before starting PrEP, healthcare providers will conduct blood tests, assess kidney function, and closely monitor both mother and child to ensure safety throughout use.

On PrEP and Mental Health

Being On PrEP affects not only physical health but also mental well-being. Many people who worry about HIV or feel anxious about unsafe sex report that consistent PrEP use reduces stress and builds confidence in their daily lives.

At the same time, some individuals may experience stigma or social judgment when others misunderstand PrEP use. This highlights the importance of counseling and mental health support alongside PrEP, ensuring that it becomes a safe and empowering experience for long-term quality of life.

On PrEP + Chemsex / Party Drugs

For individuals who engage in sex while using stimulants or recreational drugs (chemsex), the risk of HIV and other STIs is higher due to factors such as multiple partners, inconsistent condom use, or missed doses of PrEP.

Being On PrEP is therefore an important tool in reducing HIV risk in this group, ensuring protective drug levels in the body. However, PrEP does not prevent other STIs. People involved in chemsex should:

• Get regular health check-ups and STI screenings
• Always use condoms as additional protection
• Consult a healthcare provider about possible interactions between drugs and PrEP

On PrEP and Travel

For frequent travelers, being On PrEP provides peace of mind when encountering new situations abroad. However, careful planning is needed to manage medication and comply with local regulations.

Key tips for travelers on PrEP include:

• Bring enough medication for the entire trip, stored in its original packaging with prescription labels
• Check entry requirements and medication rules for the destination country
• Set reminders to avoid missed doses, especially when crossing time zones
• Prepare contact details for healthcare providers or clinics if staying abroad for an extended period

What Tests Are Needed Before Starting On PrEP?

Before beginning On PrEP, healthcare providers will run several tests to ensure both safety and effectiveness, typically including:

• HIV test to confirm the person is HIV-negative
• Kidney function test (BUN/Creatinine) since PrEP can affect renal health
• Hepatitis B and C screening to check for co-infections and determine vaccination or treatment needs
• Sexually transmitted infection (STI) screening, such as syphilis, gonorrhea, or chlamydia
• Pregnancy test for women of childbearing potential, to guide safe medication planning

These evaluations help doctors tailor PrEP use to each individual and monitor long-term safety.

Do You Still Need Condoms If You’re On PrEP?

While On PrEP is highly effective at reducing the risk of HIV, it does not protect against other sexually transmitted infections (STIs) such as syphilis, gonorrhea, chlamydia, or HPV. It also does not prevent pregnancy.

Using condoms alongside PrEP remains important because:

• They protect against other STIs
• They provide double protection for safer sex
• They enhance confidence in maintaining long-term sexual health

Therefore, combining PrEP with condoms is the safest and most comprehensive prevention strategy.

Possible Side Effects While On PrEP

In general, PrEP is well tolerated, but some people may experience temporary side effects during the initial phase, such as:

• Nausea, stomach discomfort, or mild abdominal pain
• Dizziness or fatigue
• Occasional headaches

These symptoms usually resolve within a few weeks as the body adjusts to the medication. For long-term use, doctors will monitor kidney function and perform regular blood tests to ensure continued safety.

If severe or unusual symptoms occur, PrEP should be paused and medical advice sought immediately.

What to Do If You Miss a Dose of PrEP?

Missing a dose of PrEP can reduce its effectiveness, depending on how often and how long it has been since the missed dose. General recommendations are:

• If less than 12 hours late: Take the pill as soon as you remember, then continue your next dose at the usual time.
• If more than 12 hours late: Skip the missed dose and take the next one at the regular time. Do not double up.
• If doses are missed frequently: Consult a healthcare provider, as protection may be reduced.

For those using the On-Demand (2+1+1) regimen, missed doses can have a greater impact, so specific medical guidance is essential.

FAQ: On PrEP

How long does it take for PrEP to start working?

• For anal sex: at least 7 days of daily use
• For vaginal sex or injection drug use: at least 21 days of daily use

Does PrEP protect against other STIs?
No. It only prevents HIV. Condoms are still needed for protection against other STIs.

How often do I need blood tests while On PrEP?
HIV testing every 3 months and kidney function tests every 6 months are generally recommended.

Can women use PrEP?
Yes, especially those with high-risk partners or living in areas with high HIV prevalence. Medical supervision is essential.

Conclusion: On PrEP

Being On PrEP is more than just taking medication to prevent HIV—it is an investment in long-term sexual health and overall well-being. Consistent PrEP use provides both clinically proven protection and greater confidence in relationships.

Starting PrEP should always involve medical consultation to choose the right regimen, ensure regular health monitoring, and combine with other prevention methods, such as condom use, for the most comprehensive and safe protection.

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