STDs

Sexually Transmitted Diseases

Required Reading

  • DiPiro Chapter 145

  • Alicia Potter DeFalco, Adapted from PharmD BRY

Objectives

  • Identify and utilize evidence-based resources for preventive and treatment plans for patients at risk for sexually transmitted infections (STIs).

  • Explain the therapeutic goals of pharmacologic treatment for STIs, which include:

    • Infection resolution.

    • Symptom control.

    • Prevention of complications or transmission.

  • Recognize clinical presentations of common STIs and select appropriate pharmacologic therapies based on current guidelines.

  • Describe and evaluate potential adverse effects of medications used to treat STIs, differentiating between non-life threatening and serious reactions.

  • Determine first- and second-line treatment options for specific STIs, integrating guideline recommendations and patient-specific factors.

  • Explain the importance of patient education and adherence and strategies to optimize adherence in STI management and medication selection.

Resources

  • www.cdc.gov

  • Sexually Transmitted Diseases Treatment Guidelines, 2021, Centers for Disease Control and Prevention

  • The Sanford Guide to Antimicrobial Therapy

Epidemiology of STIs

  • STIs show a higher incidence in men; however, complications tend to be more severe and frequent in women.

  • Complications caused by STIs may include:

    • Damage to reproductive organs.

    • Increased cancer risk.

    • Pregnancy complications.

    • Transmission to fetus or newborn.

  • Higher prevalence in younger populations.

  • Risk factors identified by the CDC include:

    • Number of sexual partners.

    • Men who have sex with men (MSM).

    • Prostitution.

    • Illicit drug use.

State of STIs in the United States (2024)

  • Chlamydia:

    • 1.5 million cases.

    • 4% decrease since 2020.

  • Gonorrhea:

    • 543,409 cases.

    • 20% decrease since 2020.

  • Syphilis:

    • 190,242 cases.

    • 42% increase since 2020.

  • Congenital syphilis among newborns:

    • 3,941 cases.

    • 82% increase since 2020.

Prevention Strategies

  • Male condoms:

    • Latex is more effective than lambskin.

    • Polyurethane synthetic options available.

    • Water-based lubricant recommended.

  • Female condoms:

    • Limited data on viral protection.

  • Diaphragm:

    • Limited protection.

Gonorrhea

  • Causative Agent: Neisseria gonorrhoeae, a Gram-negative diplococcus.

  • Epidemiology: 648,056 infections reported in the United States.

  • Clinical Presentation: Negitourinary (GU)

    • Men: Symptoms include dysuria, urinary frequency, and urethral discharge.

    • Women: Symptoms include vaginal discharge, uterine bleeding, dysuria, and urinary frequency.

    • Throat: Pharyngitis.

    • Anorectal: Symptoms include rectal pain, pruritus, mucopurulent discharge, and bleeding.

  • Co-infection with Chlamydia: Identified in 50% of men and 20% of women.

  • Treatment:

    • Ceftriaxone 500 mg IM x 1 (if weight ≥ 150 kg, Ceftriaxone 1 G IM x 1).

    • For uncomplicated infections, Ceftriaxone 1 G IV/IM Q24H.

    • Eye treatment: Erythromycin 0.5% ophthalmic ointment x 1 (mandatory for all infants).

    • Consideration for ophthalmia neonatorum depends on symptoms within 7 days of delivery in infants born to infected mothers.

    • Counseling for patients: Avoid intercourse for 7 days post-antibiotic treatment.

Chlamydia

  • Causative Agent: Chlamydia trachomatis, an atypical bacterium.

  • Epidemiology: 1.8 million infections reported in the United States (2019).

  • Clinical Presentation:

    • Symptoms typically appear 7–21 days after infection.

    • In men: Dysuria, urinary frequency, and urethral discharge.

    • In women: Symptoms include vaginal discharge, uterine bleeding, dysuria, and urinary frequency.

    • Throat: Pharyngitis.

    • Anorectal: Symptoms of rectal pain, pruritus, mucopurulent discharge, and bleeding.

    • Co-infection with gonorrhea is common.

  • Treatment:

    • Doxycycline 100 mg PO BID x 7 days; Azithromycin 1 g PO x 1 as alternative.

    • For uncomplicated infections: Azithromycin 1 g PO x 1; alternative: Amoxicillin 500 mg PO TID x 7 days.

    • In pregnancy: Erythromycin PO for 14 days.

    • Counseling: Avoid intercourse x 7 days after completing antibiotics, treat sex partners.

Syphilis

  • Causative Agent: Treponema pallidum, a Gram-negative spirochete.

  • Epidemiology: 207,255 cases reported in the United States; incidence rising.

  • Stages of Syphilis:

    • Primary Syphilis:

    • Incubation period ranges from 10–90 days (mean: 21 days).

    • Symptoms include a single, painless chancre lesion, which erodes and ulterates before healing within 1 – 8 weeks. The sites of infection can include the external genitalia, perianal region, mouth, or throat.

    • Secondary Syphilis:

    • Develops 2 – 8 weeks post primary infection, leading to systemic spread.

    • Clinical presentations may include a pruritic or nonpruritic rash, mucocutaneous lesions, flu-like symptoms, lymphadenopathy. If untreated, symptoms typically subside within 4 – 10 weeks, though lesions may recur within 4 years.

    • Latent Syphilis:

    • Develops 4 – 10 weeks after secondary stage, identified by positive serologic tests without further evidence of disease, asymptomatic nature.

    • Latency Stages:

      • Early Latency: 1 year from onset of infection; potentially infectious due to mucocutaneous relapse.

      • Late Latency: Noninfectious, unless transmission occurs from mother to infant.

    • Tertiary Syphilis:

    • Occurs in 30% of untreated patients within 10 – 30 years post initial infection, can manifest as both tertiary syphilis (without CNS involvement) and neurosyphilis (with CNS involvement).

    • Clinical presentations include general inflammatory reactions affecting CNS, heart, eyes, bones, and joints. Cardiovascular symptoms may present as aortitis or aortic insufficiency, while neurosyphilis may cause meningitis, paresis, dementia, blindness, or hearing loss.

    • Congenital Syphilis:

    • 3,755 cases in the United States involve transplacental transmission, with greatest risk during primary and secondary infections, leading to complications such as miscarriage, low birth weight, prematurity, cataracts, deafness, seizures, and death. Treatment includes Penicillin G IV.

  • Treatment for Syphilis:

    • **Primary, Secondary, Early Latent:

    • Benzathine penicillin G (Bicillin L-A) 2.4 million units IM x 1.

    • PCN allergy: alternative treatments include Doxycycline, Tetracycline.

    • Follow-up required at 6 and 12 months; repeat at 24 months for early latent disease.

    • Late Latent, Tertiary:

    • Benzathine penicillin G 2.4 million units IM once weekly x 3 weeks, not late by > 2 days.

    • PCN allergy alternatives: Doxycycline, Tetracycline; follow-up same as above.

    • Neurosyphilis:

    • Penicillin G 3–4 million units IV Q4H x 10 – 14 days.

    • Alternative includes Procaine penicillin 2.4 million units IM daily with probenecid 500 mg PO QID x 10 – 14 days. If allergic to penicillin, desensitization may be required. Follow-up involves CSF examination Q6 months until cell count is normal.

Genital Herpes

  • Causative Agents: Herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2).

  • Clinical Presentation:

    • Multiple painful pustular or ulcerative lesions on external genitalia and flu-like symptoms.

    • Lesions may arise in extragenital sites: eye, rectum, pharynx, fingers.

    • Potential for reactivation usually occurs near the site of the initial outbreak.

  • 1st Episode:

    • Symptoms may be asymptomatic or minimal initially. Lesions develop over 7–10 days, healing takes 2 – 4 weeks.

    • Accompanying flu-like symptoms may appear in the first few days. Other symptoms may include pruritus, vaginal or urethral discharge, paresthesia, urinary retention, with viral shedding lasting 7 – 12 days.

  • Recurrent Episodes:

    • Following prodromal symptoms in 50% of patients, including mild burning, itching, tingling. In comparison to primary infections, recurrent episodes present fewer lesions, are more localized, and have shorter symptom durations with milder symptoms. Viral shedding lasts approximately 4 days.

  • Treatment for Genital Herpes:

    • 1st Episode: No cure available, but treatment options include:

    • Acyclovir 400 mg PO TID for 7–10 days or 200 mg 5x/day.

    • Famciclovir 250 mg PO TID.

    • Valacyclovir 1 g orally BID.

    • Recurrent Episodes:

    • Episodic Therapy initiated early during recurrence can include Acyclovir, Famciclovir, or Valacyclovir for 1 – 5 days.

    • Suppressive Therapy involves daily or twice-daily Acyclovir, Famciclovir, or Valacyclovir for 1 year. Severe or complicated disease may necessitate Acyclovir IV.

Trichomoniasis

  • Causative Agent: Trichomonas vaginalis, a pear-shaped, motile, flagellated protozoan parasite.

  • Transmission: Can survive up to 45 minutes on moist surfaces, transmitted via contact with infected bathing or toilet articles and communal bathing.

  • Epidemiology: Usually asymptomatic; around 30% of patients develop symptoms.

  • Clinical Presentation:

    • In men: May present with urethral discharge, dysuria, burning, or pruritus.

    • In women: Symptoms include malodorous vaginal discharge, dysuria, pruritus, painful intercourse, and inflammation.

  • Treatment:

    • Metronidazole 500 mg PO BID x 7 days; alternative: Tinidazole 2 G PO x 1.

    • For female patients: Metronidazole 2 G PO x 1 or Tinidazole 2 G PO x 1.

    • For male patients: Metronidazole or Tinidazole 2 G PO daily x 7 days.

    • Important counseling includes: Avoid alcohol during treatment and avoid intercourse for 7 days after completing antibiotics; treat sex partners.

Human Papillomavirus (HPV)

  • Epidemiology: Most prevalent viral STD in the United States with over 150 types; 40 types associated with genital lesions.

  • Specific Types: HPV-6 and HPV-11 linked to genital warts; HPV-16 and HPV-18 associated with cervical and anal cancers.

  • Transmission: HPV utilizes skin or mucosal linings for replication via oral, genital, anal, or respiratory routes.

  • Prevention: Gardasil 9® is a nonavalent vaccine providing coverage against HPV types 6, 11, 16, 18, 31, 33, 45, 52, 58.

    • Dosing schedule: Day 1, Month 2, Month 6, or alternatively in 2 doses (first dose before age 15).

    • Indicated for males and females aged 9 – 45 years and helps prevent cervical precancers, cervical cancer, genital warts, and anal cancer with applications.

  • Treatment:

    • No cure available; treatments are symptomatic, with options varying depending on the site of infection.

Patient vs Provider Administered Therapies

  • Patient Administered Therapies include:

    • Podofilox (Condylox)

    • Imiquimod (Aldara, Zyclara)

    • Sinecatechins (Veregen)

  • Provider Administered Therapies include:

    • Cryotherapy, liquid nitrogen or cryoprobe

    • Trichloroacetic acid (TCA) or bichloroacetic acid (BCA)

    • Surgical removal for external genital and perianal warts, with TCA and BCA applied with effects including localized reactions and burning.

HPV Treatment Protocols

  • External Genital/Perianal Warts:

    • Podofilox (Condylox) 0.5% solution or gel: Induces necrosis and tissue erosion; recommended application includes treatment for up to 4 cycles with localized burning as a common side effect.

    • Imiquimod (Aldara, Zyclara) 5% cream: Enhances interferon and cytokine production, administered 3 times per week over 16 weeks; side effects may include ulceration, vesicles, localized reactions, and potential degradation of condom integrity.

    • Sinecatechins (Veregen) 15% ointment: An antioxidant therapy applied 3 times daily up to 16 weeks, with similar side effects observed. Avoid use if immunocompromised or with genital herpes.

  • Provider Administered Treatments for Condylomata:

    • Cryotherapy: Utilizes liquid nitrogen or cryoprobe.

    • TCA or BCA application: Destroys cellular proteins and induces a white frost post-application, cleansing required after treatment. Side effects may involve localized reactions.

Questions

  • Open for discussion regarding any relevant points about sexually transmitted diseases and respective treatments.