Quick clinical cards for common primary care and specialty problems. Each card highlights pathophysiology, diagnosis or tests, and first- and second-line management with U.S. brand examples.
Hypertension
Pathophys: chronic elevation in systemic vascular resistance, often driven by RAAS activation, vascular remodeling, obesity, kidney disease, or sympathetic tone. Dx: averaged office readings and home or ambulatory BP monitoring; check BMP, urinalysis, A1c, lipids, and albuminuria for target-organ risk. Tx: first line lisinopril (Prinivil, Zestril) or amlodipine (Norvasc); second line chlorthalidone (Thalitone) or losartan (Cozaar).
Coronary artery disease / stable angina
Pathophys: atherosclerotic plaque narrows coronary flow and creates demand ischemia with exertional chest pressure. Dx: ECG, troponin if acute, lipid panel, stress testing or coronary CTA when indicated. Tx: aspirin (Bayer) plus atorvastatin (Lipitor); antianginal therapy with nitroglycerin (Nitrostat) or metoprolol succinate (Toprol XL), with ranolazine (Ranexa) as a second-line add-on.
Heart failure
Pathophys: pump dysfunction and neurohormonal activation cause congestion, low output, and progressive remodeling. Dx: BNP or NT-proBNP, echocardiography, chest x-ray, renal function, and volume status. Tx: sacubitril/valsartan (Entresto) or lisinopril (Prinivil, Zestril) plus furosemide (Lasix) for congestion; add empagliflozin (Jardiance) or spironolactone (Aldactone) when appropriate.
Atrial fibrillation
Pathophys: atrial electrical disorganization and remodeling create irregular ventricular response and embolic risk. Dx: ECG, TSH, electrolytes, echo, and CHA2DS2-VASc stroke-risk assessment. Tx: anticoagulation with apixaban (Eliquis) or rivaroxaban (Xarelto); rate control with metoprolol (Toprol XL) or diltiazem (Cardizem), and rhythm control with amiodarone (Pacerone) when selected.
Hyperlipidemia
Pathophys: excess apoB/LDL particles accelerate plaque formation and vascular inflammation. Dx: fasting or nonfasting lipid panel, secondary-cause review, and ASCVD risk estimation. Tx: atorvastatin (Lipitor) or rosuvastatin (Crestor); second line ezetimibe (Zetia) or evolocumab (Repatha) for persistent LDL elevation.
Orthostatic hypotension / syncope
Pathophys: volume depletion, autonomic dysfunction, or medication effect prevents adequate BP compensation on standing. Dx: orthostatic vitals, ECG, CBC, BMP, medication review, and targeted cardiac or neuro workup if red flags appear. Tx: fluids, salt, compression, and deprescribing first; midodrine (ProAmatine) or fludrocortisone (Florinef) if persistent.
Asthma
Pathophys: chronic airway inflammation and hyperresponsiveness produce reversible bronchoconstriction and mucus plugging. Dx: spirometry with bronchodilator reversibility; consider peak flow and trigger review. Tx: budesonide-formoterol (Symbicort) or albuterol (ProAir HFA) for symptom relief; second line montelukast (Singulair) or fluticasone-salmeterol (Advair Diskus).
COPD
Pathophys: smoke or pollutant exposure drives small-airway inflammation, air-trapping, and emphysematous destruction. Dx: post-bronchodilator spirometry with FEV1/FVC below 0.70, symptom scoring, and exacerbation history. Tx: tiotropium (Spiriva) or umeclidinium-vilanterol (Anoro Ellipta); rescue albuterol (ProAir HFA) and, for selected patients, inhaled steroid combinations or roflumilast (Daliresp).
Community-acquired pneumonia
Pathophys: alveolar infection causes inflammatory consolidation and impaired gas exchange. Dx: chest x-ray, pulse oximetry, CBC, and severity assessment; cultures when severe. Tx: amoxicillin (Amoxil) or doxycycline (Vibramycin) in appropriate outpatients; second line azithromycin (Zithromax) or ceftriaxone (Rocephin) based on setting and resistance risk.
Pulmonary embolism / DVT
Pathophys: venous thrombus from stasis, injury, or hypercoagulability embolizes to the lungs or causes limb obstruction. Dx: Wells or YEARS-based approach, D-dimer when appropriate, and CT pulmonary angiography or venous ultrasound. Tx: apixaban (Eliquis) or rivaroxaban (Xarelto); second line enoxaparin (Lovenox) or warfarin (Coumadin) when DOACs are not suitable.
Obstructive sleep apnea
Pathophys: recurrent upper-airway collapse causes nocturnal hypoxemia, sleep fragmentation, and cardiometabolic risk. Dx: STOP-BANG screening plus home sleep apnea testing or polysomnography. Tx: CPAP is first line; second line mandibular advancement device, weight loss, and selected surgical options when anatomy or adherence requires it.
Tobacco use disorder
Pathophys: nicotine dependence reinforces reward pathways and drives cardiovascular, pulmonary, and cancer risk. Dx: history, readiness-to-change assessment, and comorbidity review. Tx: nicotine replacement (Nicoderm CQ, Nicorette) or varenicline (Chantix); second line bupropion SR (Zyban) plus counseling.
Type 2 diabetes
Pathophys: insulin resistance and beta-cell dysfunction lead to chronic hyperglycemia and end-organ injury. Dx: A1c, fasting glucose, or OGTT; screen kidneys, eyes, feet, and cardiovascular risk. Tx: metformin (Glucophage) or semaglutide (Ozempic) / empagliflozin (Jardiance); second line glipizide (Glucotrol) or insulin glargine (Lantus) depending on goals and control.
Hypothyroidism
Pathophys: usually autoimmune thyroid failure causes low thyroid hormone and slowed metabolism. Dx: elevated TSH with low free T4, plus thyroid antibodies when needed. Tx: levothyroxine (Synthroid, Levoxyl) is first line; liothyronine (Cytomel) is a second-line niche option in selected cases.
Hyperthyroidism / Graves disease
Pathophys: excess thyroid hormone from autoimmune stimulation or nodular autonomy raises metabolic demand. Dx: suppressed TSH, elevated T4/T3, TRAb testing, and uptake scan when needed. Tx: methimazole (Tapazole) first line; propylthiouracil (PTU) or propranolol (Inderal) for specific scenarios and symptom control.
Obesity
Pathophys: chronic positive energy balance drives adipose inflammation, insulin resistance, and cardiometabolic disease. Dx: BMI, waist circumference, complication screening, and secondary-cause review. Tx: lifestyle therapy plus semaglutide (Wegovy, Ozempic) or tirzepatide (Zepbound, Mounjaro); second line phentermine-topiramate (Qsymia) or orlistat (Xenical).
DKA / HHS
Pathophys: insulin deficiency or severe resistance causes ketogenesis, acidosis, dehydration, or hyperosmolarity. Dx: glucose, anion gap, ketones, VBG or ABG, osmolality, and precipitating-cause search. Tx: IV fluids, potassium, and regular insulin (Humulin R); transition with dextrose when the gap closes and treat the trigger.
Adrenal insufficiency
Pathophys: inadequate cortisol, and sometimes aldosterone, impairs vascular tone and stress response. Dx: morning cortisol, ACTH stimulation testing, electrolytes, and cause-directed evaluation. Tx: hydrocortisone (Cortef) first line; fludrocortisone (Florinef) for mineralocorticoid replacement when indicated, plus stress-dose education.
Stroke / TIA
Pathophys: vascular occlusion or intracranial hemorrhage abruptly deprives tissue of oxygen and glucose. Dx: urgent neuro exam, NIH Stroke Scale, noncontrast head CT, and MRI or vessel imaging as needed. Tx: ischemic stroke prevention with aspirin (Bayer) or clopidogrel (Plavix); acute reperfusion or thrombectomy when eligible and BP or anticoagulation management after the event.
Migraine
Pathophys: trigeminovascular activation and CGRP signaling produce recurrent neurovascular headache syndromes. Dx: clinical diagnosis after red flags are excluded; image when exam or history suggests secondary causes. Tx: sumatriptan (Imitrex) or NSAIDs such as ibuprofen (Advil, Motrin); second line topiramate (Topamax) or CGRP-directed prevention for frequent attacks.
Seizure disorder
Pathophys: abnormal cortical excitability can be focal or generalized and may follow structural, metabolic, or genetic triggers. Dx: EEG, brain MRI, labs for provoking factors, and seizure history. Tx: levetiracetam (Keppra) or lamotrigine (Lamictal); second line valproate (Depakote) or carbamazepine (Tegretol) based on seizure type.
Depression
Pathophys: altered monoamine signaling, stress circuitry, and inflammation contribute to mood and function decline. Dx: PHQ-9, suicide-risk assessment, and review for bipolar disorder, substance use, thyroid disease, and anemia. Tx: sertraline (Zoloft) or escitalopram (Lexapro); second line bupropion (Wellbutrin) or venlafaxine (Effexor XR) plus psychotherapy.
Anxiety disorder
Pathophys: heightened threat detection and autonomic arousal drive persistent worry, avoidance, and somatic symptoms. Dx: GAD-7 and exclusion of thyroid, stimulant, and substance causes. Tx: sertraline (Zoloft) or escitalopram (Lexapro); second line buspirone (Buspar) or hydroxyzine (Vistaril) with CBT.
Insomnia
Pathophys: hyperarousal, circadian misalignment, pain, mood disorders, and medications fragment sleep. Dx: sleep history, medication review, OSA screening, and insomnia diary. Tx: CBT-I first; if medication is needed, trazodone (Desyrel) or low-dose doxepin (Silenor), with zolpidem (Ambien) reserved for selected short-term use.
GERD
Pathophys: lower esophageal sphincter dysfunction allows acid exposure and mucosal injury. Dx: symptom history, alarm-feature review, and endoscopy or reflux testing if refractory or complicated. Tx: omeprazole (Prilosec) or pantoprazole (Protonix); second line famotidine (Pepcid) or sucralfate (Carafate) with lifestyle changes.
H. pylori / peptic ulcer disease
Pathophys: infection and acid-peptic injury erode gastric or duodenal mucosa. Dx: stool antigen or urea breath test, or endoscopy if alarm features or bleeding. Tx: bismuth quadruple therapy with a PPI such as omeprazole (Prilosec) plus bismuth, tetracycline, and metronidazole (Flagyl); second line susceptibility-guided therapy if first regimen fails.
IBS
Pathophys: gut-brain axis dysfunction and visceral hypersensitivity cause pain with altered bowel habits. Dx: Rome criteria after excluding red flags such as bleeding, anemia, weight loss, or nocturnal symptoms. Tx: fiber, low-FODMAP diet, and dicyclomine (Bentyl); second line linaclotide (Linzess) or rifaximin (Xifaxan) depending on subtype.
IBD
Pathophys: immune dysregulation causes chronic mucosal inflammation in ulcerative colitis or Crohn disease. Dx: fecal calprotectin, CRP, colonoscopy with biopsy, and cross-sectional imaging if Crohn disease is suspected. Tx: mesalamine (Lialda, Asacol) or budesonide (Entocort); second line prednisone (Deltasone) or biologics such as infliximab (Remicade) / adalimumab (Humira).
Chronic kidney disease
Pathophys: progressive nephron loss and fibrosis reduce GFR and increase albuminuria, anemia, and mineral-bone disease. Dx: eGFR, urine albumin-to-creatinine ratio, BMP, CBC, and renal imaging when indicated. Tx: lisinopril (Prinivil, Zestril) or empagliflozin (Jardiance); second line finerenone (Kerendia), diuretics, and nephrotoxin avoidance based on stage and cause.
UTI / pyelonephritis
Pathophys: bacterial ascension from the bladder can progress to renal parenchymal infection. Dx: urinalysis, urine culture, pregnancy testing when relevant, and imaging for complicated or recurrent disease. Tx: nitrofurantoin (Macrobid) or TMP-SMX (Bactrim DS) for uncomplicated cystitis; second line fosfomycin (Monurol), cephalexin (Keflex), or ceftriaxone (Rocephin) for more severe infection.
Nephrolithiasis
Pathophys: supersaturation of calcium, uric acid, cystine, or struvite crystals forms renal calculi. Dx: noncontrast CT, urinalysis, and stone analysis when recovered. Tx: ketorolac (Toradol) or ibuprofen (Advil, Motrin) for pain; tamsulosin (Flomax) for passage, with urology referral or lithotripsy for persistent obstruction.
BPH
Pathophys: androgen-dependent prostatic enlargement compresses the urethra and causes LUTS. Dx: symptom score, urinalysis, PSA when appropriate, and DRE. Tx: tamsulosin (Flomax) or alfuzosin (Uroxatral); second line finasteride (Proscar) or dutasteride (Avodart) for larger glands.
Osteoarthritis
Pathophys: mechanical cartilage loss and subchondral remodeling produce pain and stiffness. Dx: clinical pattern supported by x-ray joint-space narrowing and osteophytes when needed. Tx: acetaminophen (Tylenol) or topical diclofenac (Voltaren); second line oral NSAIDs such as naproxen (Aleve) or intra-articular corticosteroid.
Rheumatoid arthritis
Pathophys: autoimmune synovitis drives pannus formation, erosions, and systemic inflammation. Dx: anti-CCP, RF, ESR/CRP, and hand or foot imaging. Tx: methotrexate (Trexall) or hydroxychloroquine (Plaquenil); second line sulfasalazine (Azulfidine) or biologic therapy when disease remains active.
Gout
Pathophys: monosodium urate crystal deposition triggers intense neutrophilic inflammation. Dx: joint aspiration when possible, serum urate in context, and evaluation for triggers such as diuretics or renal disease. Tx: indomethacin (Indocin) or colchicine (Colcrys) for flares; second line prednisone (Deltasone) acutely and allopurinol (Zyloprim) for prevention.
Osteoporosis
Pathophys: low bone mass and increased resorption raise fragility fracture risk. Dx: DEXA, FRAX, and fracture history. Tx: alendronate (Fosamax) or zoledronic acid (Reclast); second line denosumab (Prolia) or teriparatide (Forteo) for selected patients.
Abnormal uterine bleeding / fibroids
Pathophys: ovulatory dysfunction, structural lesions, or leiomyomas create heavy or irregular bleeding and iron loss. Dx: pregnancy test, CBC, TSH as indicated, pelvic ultrasound, and endometrial biopsy when indicated by age or risk. Tx: combined oral contraceptives or levonorgestrel IUD (Mirena); second line medroxyprogesterone (Provera) or tranexamic acid (Lysteda), with fibroid-specific procedures if needed.
PCOS
Pathophys: insulin resistance and hyperandrogenism disrupt ovulation and cause metabolic risk. Dx: Rotterdam criteria with clinical or biochemical hyperandrogenism, ovulatory dysfunction, and/or polycystic ovaries after exclusion of mimics. Tx: combined OCPs such as drospirenone-ethinyl estradiol (Yaz) or metformin (Glucophage); second line spironolactone (Aldactone) or fertility-directed ovulation induction when desired.
Menopause
Pathophys: ovarian follicle depletion lowers estrogen and drives vasomotor, genitourinary, and bone symptoms. Dx: clinical history is usually enough; labs are reserved for atypical cases. Tx: estradiol (Estrace) with progesterone when indicated, or nonhormonal therapy with paroxetine (Brisdelle) or venlafaxine (Effexor XR) for hot flashes.
Cellulitis
Pathophys: skin barrier breach permits streptococcal or staphylococcal spread through the dermis and subcutis. Dx: clinical exam, risk-factor review, and culture when purulent or recurrent. Tx: cephalexin (Keflex) or dicloxacillin (Dynapen) for nonpurulent disease; second line clindamycin (Cleocin) or TMP-SMX (Bactrim DS) when MRSA coverage is needed.
Eczema / atopic dermatitis
Pathophys: barrier dysfunction and type 2 inflammation cause pruritic, relapsing dermatitis. Dx: clinical pattern, trigger review, and infection assessment if weeping or crusted. Tx: emollients plus topical corticosteroids such as triamcinolone (Kenalog) or hydrocortisone (Cortaid); second line tacrolimus (Protopic) or dupilumab (Dupixent).
Psoriasis
Pathophys: immune-mediated keratinocyte hyperproliferation produces sharply demarcated plaques and systemic inflammatory risk. Dx: clinical exam, nail findings, and biopsy if uncertain. Tx: topical corticosteroids with calcipotriene (Dovonex); second line methotrexate (Trexall), phototherapy, or biologics such as adalimumab (Humira) in moderate to severe disease.
Herpes zoster
Pathophys: reactivation of varicella-zoster virus in dorsal root ganglia causes painful dermatomal vesicles. Dx: clinical diagnosis is typical; PCR is useful when atypical. Tx: valacyclovir (Valtrex) or acyclovir (Zovirax) early, plus pain control with gabapentin (Neurontin) or other neuropathic agents if needed.