First line:

Ceftriaxone IV 2g once daily

and

Metronidazole oral 400mg 8 hourly or IV 500mg 8 hourly (only use IV if oral route compromised)

and

Doxycycline oral 100mg 12 hourly

Followed by 14 days of:

Doxycycline oral 100mg 12 hourly

and

Metronidazole oral 400mg 12 hourly

N.B. In pregnant patients, doxycycline is contraindicated.

If true penicillin / beta-lactam allergy:

Clindamycin IV 900mg 8 hourly

and

Gentamicin IV (dosing info here)

Followed by:

Clindamycin oral 450mg 6 hourly (to complete 14 days of clindamycin in total) or Doxycycline oral 100mg 12 hourly for 14 days

and

Metronidazole oral 400mg 12 hourly for 14 days

N.B. In pregnant patients, doxycycline is contraindicated.

Gentamicin should be avoided in patients with decompensated liver disease (jaundice, ascites, encephalopathy, variceal bleeding or hepato-renal syndrome).

If the use of gentamicin is contraindicated, the agent should not simply be omitted, but an alternative regimen should be chosen. 

Review gentamicin after 72 hours, as there is a risk of ototoxicity associated with prolonged use. If no positive cultures are available to guide therapy at this point, an alternative empirical regimen can be discussed with an infection specialist.

Second line:

Ofloxacin IV or oral 400mg 12 hourly for 14 days

and

Metronidazole oral 400mg 8 hourly or IV 500mg 8 hourly (only use IV if oral route compromised)

• Signs of PID include lower abdominal tenderness which is usually bilateral, fever >38°C, and adnexal or cervical motion tenderness. Due to a risk of long term sequelae in untreated disease, a low threshold for empirical treatment of suspected PID is recommended. 
• Do not remove an intra-uterine device (IUD) if present at time of diagnosis, but review after 48 hours and consider removal if no improvement. If the IUD is removed, consider the risk of pregnancy and commence alternative form of contraception.
• Take a swab for PCR for gonorrhoea & chlamydia (“NAATs”). A positive result supports PID diagnosis, but a negative result does not exclude it. All patients should be offered a pregnancy test.
• Patients should abstain from unprotected sexual intercourse until they and their partner(s) have completed treatment and follow-up.
• Refer both the case and their sexual contacts to the Sexual Health service.
• A full sexually-transmitted infection screen is advised, including HIV testing. All sexual partners should be offered, and encouraged to take up, full STI screening, including HIV testing and (if indicated) hepatitis B screening +/- vaccination. For advice or assistance with partner notification, please phone the Sexual Health Advisers on 01294 323228.