On 2014 Dec 23, David Keller commented:

Innovative antiviral delivery systems for patients non-compliant with pre-exposure prophylaxis

Pre-exposure prophylaxis (PEP) is a reasonable option when adherence to condom use is imperfect. In order to improve compliance with PEP by reducing pill burden, antiviral medication could be incorporated into oral contraceptive pills prescribed to seronegative female partners in HIV-discordant couples. In cases where the discordant seronegative partner is male, other means of reducing the pill count required to deliver PEP could be used. For example, a seronegative older man with erectile dysfunction who engages in risky behaviors could be prescribed a phosphodiesterase inhibitor pill (such as sildenafil) which also includes the recommended antiviral PEP medications.

On 2014 Dec 23, David Keller commented:

Innovative antiviral delivery systems for patients non-compliant with pre-exposure prophylaxis

Pre-exposure prophylaxis (PEP) is a reasonable option when adherence to condom use is imperfect. In order to improve compliance with PEP by reducing pill burden, antiviral medication could be incorporated into oral contraceptive pills prescribed to seronegative female partners in HIV-discordant couples. In cases where the discordant seronegative partner is male, other means of reducing the pill count required to deliver PEP could be used. For example, a seronegative older man with erectile dysfunction who engages in risky behaviors could be prescribed a phosphodiesterase inhibitor pill (such as sildenafil) which also includes the recommended antiviral PEP medications.