The right answer, before the elevator doors open.
SecondLine is a drug reference built around clinical workflow — the dose for the indication on top, the evidence one tap deeper. For residents, internists, family physicians, pharmacists, and the students becoming them.
The monograph has the data. The guidelines have the evidence. Your browser has your last three minutes. None of them have your workflow — so the answer you need first is buried under everything you already know.
SecondLine reorders the reference around the clinical question: the dose for this indication on top, off-label uses as first-class citizens, and the evidence — graded, cited, one tap away.
Amlodipine for PAH?
Watch how fast.
Type four letters → dose for the indication → off-label PAH with its guardrail → the evidence sheet.
SecondLine
amlo
Amlodipine
CardiacDihydropyridine calcium channel blocker · Norvasc
‹ Search
CardiacAmlodipine
5–10 mg
PO once daily · hypertension
L-type Ca²⁺ channel (vascular) → vasodilation, ↓ BP
Common: ankle edema · headache · flushing
Dosing by indication
Hypertension
✓ Labeled · 1st line5–10 mg once daily
Chronic stable angina
✓ Labeled5–10 mg once daily
Raynaud's phenomenon
Off-label5–10 mg once daily
Pulmonary arterial hypertension
Off-label · 1st line*WHO Group 1 — vasoreactive responders only · up to ~15–30 mg/day
*Requires positive vasoreactivity on RHCEvidence ›
Special populations
Renal · hepatic · pregnancy · elderly
Evidence — PAH, vasoreactive responders
Class effect across CCBs (best studied: nifedipine, diltiazem). Amlodipine favored when RV dysfunction makes negative inotropy a concern.
Guardrail: positive acute vasoreactivity on RHC (mPAP fall ≥10 to ≤40 mmHg). Harmful in non-responders and Group 2 PH.
Rich S, Kaufmann E, Levy PS. N Engl J Med 1992
Humbert M et al. 2022 ESC/ERS Pulmonary Hypertension Guidelines
Shelved the way you round, not the way you alphabetize.
Twenty-five categories ordered by clinical system — cardiac to antimicrobials to endocrine to neuro — so browsing feels like the wards, not an index.
Calculators
Widget board — live inputs, no navigation
CHA₂DS₂-VASc
WIDGETAnnual stroke risk
Score 3Cockcroft–Gault CrCl
WIDGET72 kg · Cr 96 µmol/L
58 mL/min
Library · 25 calculators
HEART · Wells · MELD 3.0 · QTc · FIB-4 · MME …
Calculators that live where your thumbs are.
Twenty-five clinical scores on one declarative engine — CHA₂DS₂-VASc to MELD 3.0 to Cockcroft–Gault. Pin the ones you use every shift as live widgets: real sliders, the answer recomputing as you drag, SI-first units for Canadian labs.
- ✓Every score carries its own source registry — primary literature and guidelines, cited in-app.
- ✓Widget inputs reset each launch, so patient numbers never linger.
- ✓Works offline — scores are code, not server calls.
The spectrum, before you call micro.
Antimicrobials carry a coverage map with three honest levels — and every “variable” comes with its catch spelled out, because “sometimes” is useless without the when.
Shown: ceftriaxone, from the app’s spectrum model.
Gram-positive cocci
Streptococci
MSSA
cefazolin is preferred
MRSA
Enterococci
class gap — all cephalosporins
Gram-negative bacilli
Enterobacterales
incl. β-lactamase producers
AmpC producers
may induce AmpC — avoid in serious infection
Pseudomonas aeruginosa
Gram-negative cocci
N. meningitidis
N. gonorrhoeae
Anaerobes & atypicals
Anaerobes above the diaphragm
B. fragilis (below)
add metronidazole
Atypicals
no cell wall to hit
Built for the people who carry the pager.
Residents
Mid-rounds, phone in one hand. The dose for this indication, before the attending finishes the question.
Internists & family physicians
Second-line choices with the evidence attached — is this drug still where it fits in practice, or has it been replaced?
Pharmacists
Renal cutoffs, interactions that matter, and the provenance behind every claim — graded, cited, current.
Med & pharm students
The receptor→effect logic and the clinical pearls seniors actually say — the stuff between the textbook and the ward.
From the beta cohort
“It answers the question I actually asked. Dose for the indication, then I'm back in the room.”
“The off-label uses having guardrails is the part I trust. It says when not to use it, not just when to.”
“I pinned CrCl and CHA₂DS₂-VASc as widgets and stopped opening three other apps on call.”
Everything above is one app.
Zoom out — search, dosing, evidence, spectrum, pharmacokinetics, calculators, and the pearls all live one thumb-reach apart.
Tag-based, instant, offline-capable — no network round-trip between the keystroke and the dose.
Amlodipine
Cardiac5–10 mg PO once daily · HTN
L-type Ca²⁺ (vascular) → vasodilation, ↓ BP · edema, headache, flushing
Ceftriaxone
SpectrumGram-positive cocci
Gram-negative bacilli
Gram-negative cocci
Anaerobes & atypicals
✱ MSSA: cefazolin preferred · AmpC: may induce — avoid in serious infection · B. fragilis: add metronidazole
Evidence — PAH (responders)
Rich S et al., NEJM 1992 · 2022 ESC/ERS PH Guidelines
PEARL
Amlodipine’s ankle edema is dose-related and doesn’t respond to diuretics — pair with an ACEi/ARB or step down instead.
CHA₂DS₂-VASc
Lip 2010 · ESC 2024 AF Guidelines
Apixaban — dosing
Reduce to 2.5 mg BID if ≥2 of: age ≥80 · ≤60 kg · Cr ≥133 µmol/L
Cockcroft–Gault CrCl
SI-first · inputs reset each launch
Pharmacokinetics
Hepatic CYP3A4 · <10% renal as unchanged drug
Interactions
Simvastatin: cap at 20 mg/day with amlodipine
CYP3A4 inhibitors: ↑ amlodipine exposure
Special populations
Renal: no adjustment
Elderly: start 2.5 mg
Pregnancy: limited data — specialist input
Nitroglycerin — do not use
Vancomycin — monitoring
Trough 15–20 mg/L where AUC dosing isn’t available · SCr q2–3 d
Nephrotoxicity rises with concurrent pip-tazo
Metformin
Endocrine500 mg BID with meals · T2DM
Titrate weekly to 1 g BID · avoid if eGFR <30 · don’t start at 30–45
Evidence — AF, stroke prevention
ARISTOTLE, NEJM 2011 · CCS 2020 AF Guidelines — DOAC over warfarin
Wells — PE
PE most likely dx · +3.0
HR 112 · +1.5
Immobilization · +1.5
Browse by system
Side effects
Expected pharmacology — distinct from toxicity
Empagliflozin — MOA
Blocks SGLT2 in the proximal tubule → glycosuria + natriuresis.
Cardiorenal benefit persists at eGFR too low for meaningful glucose lowering — the mechanism isn’t the glucose.
Evidence — HFrEF
EMPEROR-Reduced, NEJM 2020 · CCS/CHFS 2021 HF Guidelines
MELD 3.0
Bili 58 µmol/L · INR 1.6 · Cr 110 · Na 131 · Alb 30
QTc
QT 400 ms · HR 88
Bazett over-corrects when tachycardic
PEARL
Metformin isn’t held for every contrast study — only eGFR <30, AKI, or intra-arterial with first-pass renal exposure.
Opioid MME
Oxycodone 20 mg PO q6h
≥90 MME/day — reassess before escalating
Current use in IM
✓ Still first-line
CCB of choice for HTN (Hypertension Canada) — long t½ forgives a missed dose.
PEARL
Furosemide PO→IV is 2:1 — and oral absorption is erratic in decompensated HF, so gut edema, not the dose, is often the problem.
Every field carries its source
Tertiary references are verified against, never ingested — and nothing ships until a physician has reviewed the row.
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