Combined Oral Contraceptives (COCs)
Mechanism
Estrogen + progestin โ suppress LH surge โ prevent ovulation; thicken cervical mucus; thin endometrium
| Component | Effect | Side Effects |
|---|---|---|
| Estrogen (ethinyl estradiol) | Suppress FSH/LH; stabilize endometrium | Nausea, breast tenderness, thromboembolic risk |
| Progestin | Suppress LH; cervical mucus thickening | Mood changes, acne, decreased libido |
Contraindications (ACHES Mnemonic)
MnemonicA โ Abdominal pain (thrombosis); C โ Chest pain (MI/PE); H โ Headache severe (stroke); E โ Eye changes (vision loss); S โ Severe leg pain (DVT)
Boards PearlCOCs are CONTRAINDICATED in: smokers โฅ35 yo, migraines with aura, personal hx DVT/PE, active liver disease, uncontrolled HTN, ischemic heart disease, breast cancer. Also avoid within 3 weeks postpartum (if not breastfeeding) due to VTE risk.
Non-Contraceptive Benefits
- Reduce ovarian and endometrial cancer risk
- Treat dysmenorrhea, endometriosis, PCOS (acne, irregular cycles)
- Decrease menstrual blood loss (anemia)
- Suppress functional ovarian cysts
Progestin-Only Pills (POPs / "Mini-Pill")
Norethindrone โ primarily thickens cervical mucus; must be taken same time daily (ยฑ3 hr window); safe in breastfeeding, smokers โฅ35, migraine with aura, HTN
Boards PearlNorethindrone POP: no estrogen CI applies. If pill taken >3 hrs late โ use backup for 48 hrs. Irregular bleeding is common side effect.
Emergency Contraception
| Agent | Mechanism | Window | Notes |
|---|---|---|---|
| Levonorgestrel (Plan B) | Inhibits/delays ovulation | Within 72 hrs (up to 120 hrs) | OTC; less effective if BMI >75kg; no effect if already ovulated |
| Ulipristal acetate (ella) | Progesterone receptor modulator; delays/inhibits ovulation | Within 120 hrs | Rx required; more effective than LNG near 72โ120 hr window; avoid with hormonal contraception |
| Copper IUD (Paragard) | Toxic to sperm; prevents fertilization/implantation | Within 120 hrs | Most effective EC (>99%); provides ongoing contraception for 10+ years |
Clinical NoteCopper IUD is preferred EC for women who also want long-term contraception. Ulipristal is superior to levonorgestrel for women >165 lbs. LNG EC is safest OTC option and does NOT cause abortion.
Long-Acting Contraceptives & Hormonal Therapies
LARC Options
| Method | Drug | Duration | Key Points |
|---|---|---|---|
| LNG-IUD | Mirena (52mg), Kyleena (19.5mg) | 5โ8 yrs | Reduces menstrual bleeding; amenorrhea in 20%; treats AUB/endometriosis |
| Copper IUD | Paragard | 10+ yrs | Non-hormonal; heavier periods; best for hormone-CI patients |
| Implant | Nexplanon (etonogestrel) | 3 yrs | Subdermal arm implant; irregular bleeding common; most effective reversible method |
| Depot shot | Depo-Provera (DMPA) | 3 months | Bone density decrease with prolonged use; fertility may delay 12โ18 months after stopping |
| Patch | Xulane (EE/norelgestromin) | Weekly x3 | Higher VTE risk than pills; less effective if >90kg |
| Ring | NuvaRing (EE/etonogestrel) | 3 weeks | Vaginal insertion; similar CI as COCs |
Spironolactone for PCOS/Hirsutism
Aldosterone antagonist + anti-androgen โ blocks androgen receptors โ reduces hirsutism, acne in PCOS. Dose: 50โ200 mg/day. Monitor Kโบ (hyperkalemia risk). CI in pregnancy (feminizes male fetus). Combine with OCP for contraception.
Boards PearlSpironolactone = first-line for hirsutism in PCOS when OCPs insufficient. Also used for female-pattern hair loss. Monitor potassium, especially if on ACE-I/ARB.
Menopause Hormone Therapy (MHT/HRT)
| Type | Use Case | Risk Consideration |
|---|---|---|
| Estrogen only | Post-hysterectomy women | Reduces VMS, prevents bone loss |
| Estrogen + progestin | Women with uterus | Progestin protects against endometrial cancer; slight โ breast cancer risk with long-term use |
| Vaginal estrogen | GSM (atrophic vaginitis) | Minimal systemic absorption; safe in most patients |
GnRH Agonists & Antagonists
Leuprolide (Lupron) โ GnRH Agonist
Continuous administration โ downregulates GnRH receptors โ โ FSH/LH โ โ estrogen/testosterone ("medical castration")
Indications
- Endometriosis (reduces lesion size, pain)
- Uterine fibroids (preoperative shrinkage)
- Precocious puberty
- Prostate cancer (androgen deprivation)
- Breast cancer (premenopausal, hormone receptor+)
- Fertility treatment (prevent premature LH surge)
Boards PearlInitial "flare effect" โ first 1โ2 weeks of leuprolide causes transient โ testosterone (can worsen prostate cancer symptoms). Prevent with anti-androgen (bicalutamide) for first 2โ4 weeks. Long-term: hot flashes, bone loss, decreased libido.
Elagolix (Orilissa) โ GnRH Antagonist
Immediate suppression (no flare); oral; indicated for endometriosis pain. Lower dose: partial estrogen suppression. Higher dose: full suppression (used โค6 months due to bone loss).
Methotrexate for Ectopic Pregnancy
Folate antagonist โ inhibits DNA synthesis โ kills rapidly dividing trophoblastic cells
Criteria for Medical MgmtHemodynamically stable; unruptured; hCG <5000 (ideally <3000); no cardiac activity on US; no significant free fluid; willing/able to follow-up
Boards PearlAfter MTX for ectopic: avoid NSAIDs (reduce efficacy), folate supplements, alcohol, sunlight. Serial hCG q48h โ should decrease โฅ15% from day 4โ7. If not, repeat dose or surgery. Contraindicated: immunodeficiency, thrombocytopenia, hepatic/renal disease, breastfeeding, intrauterine pregnancy.
UTI & Pyelonephritis Antibiotics
Uncomplicated Cystitis (Women)
| Drug | Dose/Duration | Notes |
|---|---|---|
| Nitrofurantoin (Macrobid) | 100mg BID x 5 days | First-line; only urinary tract; CI if eGFR <30; avoid at term pregnancy |
| TMP-SMX (Bactrim DS) | 1 tab BID x 3 days | First-line if local resistance <20%; CI in sulfa allergy, G6PD deficiency, folate deficiency |
| Fosfomycin (Monurol) | 3g x 1 dose | Single dose; excellent for resistant organisms including ESBL; expensive |
| Pivmecillinam | 400mg BID x 3โ7 days | Limited US availability; good for E. coli |
| Fluoroquinolones (Cipro/Levaquin) | 3โ7 days | Reserve for complicated UTI or pyelonephritis due to resistance; FDA black box: tendinopathy, aortic aneurysm |
Boards PearlAvoid fluoroquinolones for uncomplicated UTI (preserve for more serious infections). Nitrofurantoin does NOT achieve adequate renal tissue levels โ NOT for pyelonephritis.
Pyelonephritis
| Setting | Treatment | Duration |
|---|---|---|
| Outpatient (mild-mod) | Ciprofloxacin 500mg BID or TMP-SMX DS BID (if susceptible) | 7โ14 days |
| Inpatient (moderate) | IV ceftriaxone or IV ciprofloxacin | 14 days total (IVโPO step-down) |
| Severe/septic | IV pip-tazo or meropenem (if ESBL suspected) | 14 days |
| Pregnancy | IV cephalosporin (ceftriaxone); hospitalize | 14 days |
Recurrent UTI Prophylaxis
- Nitrofurantoin 50โ100mg QHS (continuous) or post-coital
- TMP-SMX 40/200mg QHS
- Vaginal estrogen in postmenopausal women (reduces recurrence significantly)
- D-mannose (OTC; some evidence for prevention)
STI Treatments
| STI | First-Line Treatment | Notes |
|---|---|---|
| Gonorrhea (N. gonorrhoeae) | Ceftriaxone 500mg IM x1 (if >150kg: 1g) | No longer treat with azithromycin combo; test-of-cure if pharyngeal; treat partners |
| Chlamydia (C. trachomatis) | Doxycycline 100mg BID x 7 days | Preferred over azithromycin (better cure rates for rectal); PID treat 14 days |
| Syphilis (T. pallidum) โ Primary/Secondary | Benzathine penicillin G 2.4 million units IM x1 | PCN allergy: doxycycline 100mg BID x14d; neurosyphilis: IV aqueous PCN G |
| Syphilis โ Tertiary/Latent (>1yr) | Benzathine PCN G 2.4M units IM weekly x3 | Cannot use doxy for late latent; desensitize if PCN allergic |
| Trichomonas vaginalis | Metronidazole 2g PO x1 OR 500mg BID x7d | Treat partners; avoid alcohol during and 48h after; tinidazole 2g x1 alternative |
| BV (Gardnerella) | Metronidazole 500mg BID x7d OR vaginal gel x5d | Clindamycin 300mg BID x7d if metro-intolerant; recurrence common; treat symptomatic pregnant women |
| HSV-2 (genital herpes) โ 1st episode | Acyclovir 400mg TID x7โ10d OR valacyclovir 1g BID x7โ10d | Start within 72h; suppressive therapy: valacyclovir 500mg daily reduces outbreaks and transmission |
| HSV โ Recurrence | Valacyclovir 500mg BID x3d OR 1g daily x5d | Start at prodrome; reduces duration/severity |
| HPV-related warts | Patient: imiquimod cream, podofilox; Provider: trichloroacetic acid, cryotherapy, surgical | Prevention: Gardasil-9 vaccine up to age 45; no treatment clears infection, only lesions |
| PID | Outpt: Ceftriaxone 500mg IM + doxycycline 100mg BID x14d ยฑ metronidazole 500mg BID x14d | Inpt: IV cefoxitin + doxy OR clindamycin + gentamicin; hospitalize if pregnancy, severe illness, no improvement in 72h, TOA |
Clinical NoteAlways screen and treat partners for gonorrhea/chlamydia/trich/syphilis. Report to public health. Test of cure for gonorrhea in throat and rectum. NAAT is gold standard for chlamydia/gonorrhea diagnosis.
Boards PearlJarisch-Herxheimer reaction: fever, rigors, myalgias within 24h of penicillin for syphilis treatment (especially 1ยฐ and 2ยฐ syphilis). Treat with antipyretics; not an allergy. Warn patients, especially pregnant women (can trigger preterm labor).
OB Medications
Oxytocin (Pitocin)
Synthetic oxytocin โ uterine smooth muscle contraction via oxytocin receptors; also used for postpartum hemorrhage (PPH) prevention
| Indication | Use | Key Points |
|---|---|---|
| Labor induction/augmentation | IV infusion, titrated | Risk: uterine hyperstimulation, fetal distress, water retention (antidiuretic effect at high doses) |
| Postpartum hemorrhage | 10โ40 units IV or IM | First-line PPH treatment; uterine atony = #1 cause PPH |
| Incomplete abortion | IV infusion | Promotes uterine contraction to expel retained products |
Magnesium Sulfate (MgSOโ)
Indications
- Eclampsia prevention and treatment (seizes prophylaxis in severe preeclampsia)
- Neuroprotection for premature infant (<32 weeks gestation)
- Tocolysis (short-term, 48 hours โ not first-line)
Boards PearlMg toxicity progression: Loss of DTRs (9โ12 mEq/L) โ respiratory depression (12โ15 mEq/L) โ cardiac arrest (>15 mEq/L). Antidote: Calcium gluconate 1g IV. Monitor UO, DTRs, RR. Therapeutic level for seizure prophylaxis: 4โ7 mEq/L.
Labetalol & Hydralazine for Acute Severe HTN in Pregnancy
| Drug | Dose | Notes |
|---|---|---|
| Labetalol | 20mg IV bolus q10min (max 300mg total) | Alpha + beta blocker; safe in pregnancy; avoid if asthma/bradycardia |
| Hydralazine | 5โ10mg IV q20min (max 30mg) | Direct vasodilator; reflex tachycardia; neonatal thrombocytopenia risk |
| Nifedipine IR | 10mg PO q20min x3 | CCB; oral option; avoid sublingual (rapid drop in BP, fetal distress) |
Treatment TargetSBP <160 mmHg and DBP <110 mmHg within 30โ60 minutes in severe-range BP to prevent maternal stroke. Chronic HTN in pregnancy: labetalol, nifedipine (extended-release), or methyldopa (safe but less preferred due to side effects).
Tocolytics
| Drug | Mechanism | Use | Notes |
|---|---|---|---|
| Nifedipine | CCB โ โ myometrial Caยฒโบ | First-line tocolytic | Safe, oral, effective for 48h (time for steroids) |
| Indomethacin | COX inhibitor โ โ prostaglandins | Up to 32 weeks | Risk: premature closure ductus arteriosus, fetal renal toxicity; short term only |
| Magnesium sulfate | Caยฒโบ antagonist | <32 weeks (neuroprotection) | Primary neuroprotective benefit; least effective tocolytic |
Antenatal Corticosteroids
Betamethasone 12mg IM q24h x2 doses (or dexamethasone 6mg IM q12h x4 doses) โ for fetal lung maturation when preterm birth anticipated at 24โ34 weeks. Reduces RDS, IVH, necrotizing enterocolitis, and neonatal mortality.
BPH & Prostate Drugs
Alpha-1 Blockers (First-Line)
| Drug | Selectivity | Key Notes |
|---|---|---|
| Tamsulosin (Flomax) | ฮฑ1A selective (prostate) | Least hypotension; take 30 min after meal; intraoperative floppy iris syndrome (IFIS) โ tell ophthalmologist |
| Silodosin (Rapaflo) | ฮฑ1A highly selective | Retrograde ejaculation common |
| Alfuzosin (Uroxatral) | ฮฑ1 non-selective | Less sexual side effects than tamsulosin |
| Doxazosin (Cardura) | ฮฑ1 non-selective | Also treats HTN; orthostatic hypotension; titrate slowly |
| Terazosin | ฮฑ1 non-selective | Also treats HTN; take at bedtime; first-dose hypotension |
Boards PearlIFIS (intraoperative floppy iris syndrome) โ alpha-1 blockers (especially tamsulosin) cause iris dilator muscle atrophy โ iris prolapse during cataract surgery. Patient must tell surgeon BEFORE eye surgery even if drug was stopped.
5-Alpha Reductase Inhibitors (5-ARIs)
| Drug | Isoenzyme | Notes |
|---|---|---|
| Finasteride (Proscar/Propecia) | 5-AR type 2 only | BPH: 5mg; male pattern baldness: 1mg. Decreases PSA by 50% after 6 months โ double measured PSA to get true value. 3โ6 month onset. Sexual dysfunction: decreased libido, ED, gynecomastia. CI: pregnancy (teratogenic) |
| Dutasteride (Avodart) | 5-AR type 1 & 2 | More complete DHT suppression. Same onset/side effects as finasteride. Also decreases PSA by 50%. |
Combination Therapy & PDE5 Inhibitors
Alpha-blocker + 5-ARI (e.g., Jalyn = dutasteride + tamsulosin): most effective for large prostates, reduces risk of acute urinary retention and need for surgery (CombAT trial).
Tadalafil (Cialis) 5mg daily: PDE5 inhibitor approved for BPH ยฑ erectile dysfunction; relaxes prostate/bladder smooth muscle; do NOT combine with nitrates (risk of severe hypotension).
Prostate Cancer Pharmacotherapy
| Drug Class | Examples | Use |
|---|---|---|
| GnRH agonists (ADT) | Leuprolide, goserelin | Androgen deprivation therapy; metastatic/advanced PCa |
| GnRH antagonists | Degarelix, relugolix | No flare; immediate testosterone suppression |
| Anti-androgens | Bicalutamide, enzalutamide, apalutamide | Block androgen receptor; castration-resistant PCa |
| CYP17 inhibitors | Abiraterone (+ prednisone) | Blocks androgen synthesis; CRPC pre/post-chemo |
Clinical NotePSA screening: USPSTF recommends shared decision-making for men 55โ69 yo (Grade C). Not recommended for men โฅ70 (Grade D). PSA >4 ng/mL or velocity >0.75 ng/mL/year โ urology referral. Normal PSA does not exclude PCa.