Treatment of STDs Flashcards
ANTIVIRALS
Acyclovir
Famciclovir
Valacyclovir
ANTIMICROBIALS
Amoxicillin Azithromycin Cefixime Ceftriaxone Clindamycin Doxycycline Erythromycin Levofloxacin Metronidazole Ofloxacin Penicillin G Tinidazole
ANTIFUNGALS
Butoconazole Clotrimazole Fluconazole Miconazole Terconazole Tioconazole
HPV Rx
Cervarix Gardisil Podofilox Imiquimod Sinecatechins
HSV: Treatment
Acyclovir
Famciclovir
Valacyclovir
MECHANISM OF ACTION: Acyclovir & Valacyclovir
Competitively inhibits viral DNA polymerase; competes with deoxyguanosine triphosphate for incorporation into viral DNA.
MECHANISM OF ACTION: Famciclovir
Famciclovir is metabolized (de-acetylated) to penciclovir. Does not cause chain termination
Metab/Elim: Acyclovir & Valacyclovir
Little metabolism; renal elimination; dose adjust in renal dysfunction or failure may occur.
Toxicity: Acyclovir & Valacyclovir
Neurotoxicity incl seizures
Patients taking Acyclovir & Valacyclovir?
Needs to be well hydrated to avoid crystalline nephropathy or neurotoxicity.
Syphilis: Treponema palladium treatment?
Benzathine Penicillin G, IM
MECHANISM OF ACTION: Benzathine Penicillin G
Bactericidal beta-lactam: binds PBPs causing cell lysis
Benzathine Penicillin G administration:
Produces a drug depot that liberates drug over 2 weeks following 1.2 x106.
Benzathine Penicillin G has poor
Penetration of CSF - Not good for neurosyphilis
Benzathine Penicillin G eliminated & hypersensitivity?
Rapidly eliminated via renal tubular excretion.
Significantly delayed in patients with decreased renal function.
Hypersensitivity or skin rashes may be problematic.
Latent Syphilis Sero-reactivity w/o other evidence of disease treatment?
- Not sexually transmitted – treatment to prevent complications
- Early Latent: Benzathine Pen G 2.4 x 106 units IM dose
Congenital Syphilis treatment
Aqueous crystalline Penicillin G
Procaine Penicillin G
Jarisch-Herxheimer Reaction?
70-90% with secondary syphilis several hours after first injection of penicillin.
Chills, fever, headache, myalgias, and arthralgias
Syphilitic cutaneous lesions may become more
prominent, edematous, and brilliant in color
Few hours; begins to fade within 48 hr and does not re-occur.
Jarisch-Herxheimer Reaction mechanism & treatment?
Release of spirochetal antigens with subsequent host reactions to the products
Aspirin gives symptomatic relief
Do NOT discontinue penicillin therapy
Chlamydia is?
The most common STD in the US
Chlamydia treatment
Azithromycin Doxycycline Erythromycin base Levofloxacin Ofloxacin
Azithromycin DRUG MECHANISM:
Binds 50S ribosomal subunit: bacteriostatic
Doxycycline DRUG MECHANISM:
Binds 30S ribosomal subunit: bacteriostatic
Erythromycin base DRUG MECHANISM:
Binds 50S ribosomal subunit: bacteriostatic
Levofloxacin DRUG MECHANISM:
Inhibits DNA gyrase (topo II) in gram-negative:
bactericidal
Inhibits topo IV in gram-positive: bactericidal
Ofloxacin DRUG MECHANISM:
Inhibits DNA gyrase (topo II) in gram-negative:
bactericidal
Inhibits topo IV in gram-positive: bactericidal
Amoxicillin DRUG MECHANISM:
Bactericidal beta-lactam: binds PBPs causing cell lysis.
Erythromycin base elimination:
P-gp & CYP3A4 substrate & inhibitor; minimal elim in urine most in stool.
Azithromycin Side effects:
GI upset; vaginitis
Doxycycline Side effects:
GI upset; hepatic damage in high dose esp in pregnancy; photosensitivty with sunlight or tanning bed
Erythromycin base Side effects:
GI upset; increases toxicity of CYP3A4 substrates; estolate preparations may cause cholestatic jaundice; risk of sudden cardiac death with CYP3A4 inhibitors
Levofloxacin & Ofloxacin Side effects:
Taste disturbance (levo); GI upset; BBW of increase risk of tendonitis & rupture; BBW of exacerbation of muscle weakness – avoid with myasthenia gravis.
Chancroid is
Painful necrotizing genital ulcers
Chancroid treatment
Azithromycin
Ceftriaxone
Ciprofloxacin
Erythromycin base
Chancroid Successful treatment:
Cures infection & resolves symptoms; advanced cases may suffer permanent scarring.
Ceftriaxone DRUG MECHANISM:
Bactericidal beta-lactam: binds PBPs causing cell lysis.
Ciprofloxacin DRUG MECHANISM:
Inhibits DNA gyrase (topo II) in gram-negative: bactericidal
Inhibits topo IV in gram-positive: bactericidal
Ciprofloxacin Distributes into
Breast milk and crosses placenta. No pattern of adverse events recognized but from abundance of caution drug not recommended in these situations
Uncomplicated Gonococcal Infections
cervix, urethra, rectum
TREATMENT:
Ceftriaxone
Cefixime
Plus
Azithromycin or Doxycycline
Uncomplicated Gonococcal Infections
pharynx
TREATMENT:
Ceftriaxone
Plus
Azithromycin or Doxycycline
Cefixime DRUG MECHANISM:
Bactericidal beta-lactam: binds PBPs causing cell lysis
Cefixime ELIMINATION
Penetrates urine, prostatic and blister fluids; eliminated unchanged primarily in urine by GF and RTS
Cefixime Side effects:
Diarrhea & GI upset. Rarely may é clotting time.
False positive for urinary glucose in diabetic patients
Urethritis - Cervicitis TREATMENT:
Azithromycin Doxycycline Erythromycin base Levofloxacin Ofloxacin
Recurrent Treatment
Urethritis - Cervicitis
Metronidazole or Tinidazole
Plus
Azithromycin
Trichomoniasis TREATMENT:
Metronidazole
Tinidazole
Metronidazole & Tinidazole DRUG MECHANISM:
Amebicidal, bactericidal, and trichomonacidal
Unionized drug taken up by anaerobic organisms and cells where it is reduced to its active form which disrupts DNA’s helical structure, thereby inhibiting bacterial nucleic acid synthesis. Equally effective vs. dividing and non-dividing cells.
Metronidazole & Tinidazole elimination:
Elimination primarily in urine (discoloration) and stool.
Metronidazole & Tinidazole side effects & CI:
Avoid in pregnancy and breastfeeding; GI upset; candidiasis; disulfiram-like effect (avoid alcohol for 24 hr (M) or 72 hr (T). Tinidazole AFTER completing therapy; 2° malignancies in animal model.
Bacterial Vaginosis TREATMENT:
Metronidazole
Clindamycin
Tinidazole
Clindamycin
Clindamycin DRUG MECHANISM:
Binds 50s ribosomal subunit to inhibit protein synthesis; bacteriostatic
Clindamycin ISSUES:
CDC recommends intravaginal use only in 1st trimester due to an increase in adverse events, such as low birthweight, pre-term delivery, premature rupture of the membranes, and neonatal infections if used after 16 weeks.Excreted in breast milk – AAP sees no issues but manufacturer advises caution. GI upset most commonly with systemic drug BUT also reported with intravaginal application. Local delivery also rarely associated with contact toxicity like vaginal erythema, vulvovaginal pruritus, vaginal discharge, vaginal swelling, vaginal bleeding and vaginal pain.
Candidiasis TREATMENT:
Butoconazole Clotrimazole Miconazole Tioconazole PRESCRIPTION Butoconazole Terconazole Fluconazole
Conazoles Mechanism:
Blocks ergosterol synthesis through interacting with 14-alpha demethylase, a CYP necessary conversion of lanosterol to ergosterol; essential membrane component.
Fluconazole distrubted & eliminated:
Widely distributed in tissues and fluids; renal elimination – predominantly unchanged.
High systemic doses of azoles produce?
Abdominal wall defects & cleft palate in fetus & maternal stress.
Recommended avoid in 1st trimester
Oil-based topical Conazoles products:
Can weaken latex condoms or diaphragms.
HPV: Prevention
Human Papillomavirus vaccine [Gardasil & Cervarix]
Gardasil & Cervarix Mechanism:
Both contain recombinant L1 protein, the major antigenic protein of the capsid of HPV
Gardasil: Types?
Types 6, 11, 16, & 18 (quadrivalent)
Cervarix: Types?
Types 16 & 18 (bivalent)
HPV: Prevention Recommended for?
Recommended girls & boys, men & women <26 y/o and receive 3 doses at 0, 2 & 6 months
Genital Warts caused by?
90% caused by HPV 6 & 11
Genital Warts symptoms & infection
Usually asymptomatic but can be painful and pruritic
Available treatments likely reduce but probably don’t erradicate HPV infectivity
Genital Warts TREATMENTS:
Podofilox
Imiquimod
Sinecatechins
Podofilox Mechanism & administration:
A plant-derived mitotic spindle inhibitor blocking microtubular activity in keratinocytes
Topical gel: little if any drug systematization
Imiquimod Mechanism, administration & elimination:
An immune response modifier
Topical gel: absorption = surface area»_space; amount applied
Eliminated in urine
Sinecatechins Mechanism & side effect:
Agreen tea extract antioxidant
Pain and discomfort at application site