Pharmacology Drug Classification - Easy Memory Guide

from reportlab.lib.pagesizes import A4
from reportlab.lib import colors
from reportlab.lib.styles import getSampleStyleSheet, ParagraphStyle
from reportlab.lib.units import mm, cm
from reportlab.platypus import (
    SimpleDocTemplate, Paragraph, Spacer, Table, TableStyle,
    PageBreak, HRFlowable, KeepTogether
)
from reportlab.lib.enums import TA_CENTER, TA_LEFT, TA_JUSTIFY
from reportlab.platypus import Flowable

# ── Colour palette ────────────────────────────────────────────────────────────
C_DARK_BLUE   = colors.HexColor("#1A3A5C")
C_MED_BLUE    = colors.HexColor("#2E6DA4")
C_LIGHT_BLUE  = colors.HexColor("#D6E8F7")
C_TEAL        = colors.HexColor("#0D7377")
C_LIGHT_TEAL  = colors.HexColor("#C8ECED")
C_GREEN       = colors.HexColor("#1B7A3E")
C_LIGHT_GREEN = colors.HexColor("#D4EDDA")
C_ORANGE      = colors.HexColor("#C0510E")
C_LIGHT_ORANGE= colors.HexColor("#FDEBD0")
C_PURPLE      = colors.HexColor("#5B2C8A")
C_LIGHT_PURPLE= colors.HexColor("#EDE0F5")
C_RED         = colors.HexColor("#B71C1C")
C_LIGHT_RED   = colors.HexColor("#FDECEA")
C_YELLOW      = colors.HexColor("#F5C518")
C_LIGHT_YELLOW= colors.HexColor("#FFF9E6")
C_GRAY        = colors.HexColor("#F4F6F9")
C_DARK_GRAY   = colors.HexColor("#444444")
C_WHITE       = colors.white

# ── Document setup ────────────────────────────────────────────────────────────
doc = SimpleDocTemplate(
    "/tmp/workspace/pharma-guide/Pharmacology_Drug_Classification.pdf",
    pagesize=A4,
    rightMargin=15*mm, leftMargin=15*mm,
    topMargin=18*mm, bottomMargin=18*mm,
    title="Pharmacology Drug Classification - Easy Memory Guide",
    author="Medical Study Guide"
)
W = A4[0] - 30*mm   # usable width

styles = getSampleStyleSheet()

# ── Custom styles ─────────────────────────────────────────────────────────────
def S(name, **kw):
    return ParagraphStyle(name, **kw)

sTitle = S("sTitle",
    fontName="Helvetica-Bold", fontSize=22, textColor=C_WHITE,
    alignment=TA_CENTER, spaceAfter=4)

sSub = S("sSub",
    fontName="Helvetica", fontSize=11, textColor=C_LIGHT_BLUE,
    alignment=TA_CENTER, spaceAfter=2)

sH1 = S("sH1",
    fontName="Helvetica-Bold", fontSize=14, textColor=C_WHITE,
    spaceAfter=4, spaceBefore=8, leftIndent=6)

sH2 = S("sH2",
    fontName="Helvetica-Bold", fontSize=11, textColor=C_DARK_BLUE,
    spaceAfter=3, spaceBefore=6)

sBody = S("sBody",
    fontName="Helvetica", fontSize=8.5, textColor=C_DARK_GRAY,
    spaceAfter=2, leading=12)

sTip = S("sTip",
    fontName="Helvetica-BoldOblique", fontSize=8.2, textColor=C_GREEN,
    spaceAfter=3, spaceBefore=2, leftIndent=6)

sSmall = S("sSmall",
    fontName="Helvetica", fontSize=7.8, textColor=C_DARK_GRAY,
    leading=11)

sBullet = S("sBullet",
    fontName="Helvetica", fontSize=8.5, textColor=C_DARK_GRAY,
    leftIndent=12, spaceAfter=1, leading=12, bulletIndent=4)

sCode = S("sCode",
    fontName="Courier", fontSize=8, textColor=C_DARK_BLUE,
    leftIndent=10, spaceAfter=1, leading=11)

# ── Helpers ───────────────────────────────────────────────────────────────────
def section_banner(text, bg=C_MED_BLUE):
    """Coloured full-width section banner."""
    data = [[Paragraph(text, sH1)]]
    t = Table(data, colWidths=[W])
    t.setStyle(TableStyle([
        ("BACKGROUND", (0,0), (-1,-1), bg),
        ("TOPPADDING",    (0,0), (-1,-1), 5),
        ("BOTTOMPADDING", (0,0), (-1,-1), 5),
        ("LEFTPADDING",   (0,0), (-1,-1), 8),
        ("RIGHTPADDING",  (0,0), (-1,-1), 8),
        ("ROUNDEDCORNERS", [4]),
    ]))
    return t

def tip_box(text, bg=C_LIGHT_GREEN, border=C_GREEN):
    data = [[Paragraph("💡 " + text, sTip)]]
    t = Table(data, colWidths=[W])
    t.setStyle(TableStyle([
        ("BACKGROUND",    (0,0), (-1,-1), bg),
        ("LINEBELOW",     (0,0), (-1,-1), 1.2, border),
        ("LINEBEFORE",    (0,0), (-1,-1), 3,   border),
        ("TOPPADDING",    (0,0), (-1,-1), 4),
        ("BOTTOMPADDING", (0,0), (-1,-1), 4),
        ("LEFTPADDING",   (0,0), (-1,-1), 8),
    ]))
    return t

def make_table(headers, rows, col_widths, hdr_bg=C_DARK_BLUE, hdr_fg=C_WHITE,
               alt_bg=C_GRAY, border=C_MED_BLUE):
    hdr_cells = [Paragraph(f"<b>{h}</b>", S("th",
        fontName="Helvetica-Bold", fontSize=8.5, textColor=hdr_fg,
        alignment=TA_CENTER, leading=11)) for h in headers]
    data = [hdr_cells]
    for i, row in enumerate(rows):
        cells = [Paragraph(str(c), sSmall) for c in row]
        data.append(cells)

    t = Table(data, colWidths=col_widths, repeatRows=1)
    style_cmds = [
        ("BACKGROUND",    (0,0), (-1,0),  hdr_bg),
        ("GRID",          (0,0), (-1,-1), 0.4, border),
        ("TOPPADDING",    (0,0), (-1,-1), 3),
        ("BOTTOMPADDING", (0,0), (-1,-1), 3),
        ("LEFTPADDING",   (0,0), (-1,-1), 5),
        ("RIGHTPADDING",  (0,0), (-1,-1), 5),
        ("VALIGN",        (0,0), (-1,-1), "MIDDLE"),
        ("ROWBACKGROUNDS",(0,1), (-1,-1), [C_WHITE, alt_bg]),
    ]
    t.setStyle(TableStyle(style_cmds))
    return t

def sp(n=4):
    return Spacer(1, n)

# ── Build story ───────────────────────────────────────────────────────────────
story = []

# ═══════════════════════════════════════════════════════════════════════════════
# COVER HEADER
# ═══════════════════════════════════════════════════════════════════════════════
cover_title = [[Paragraph("PHARMACOLOGY", sTitle),
                Paragraph("Drug Classification - Easy Memory Guide", sSub),
                Paragraph("MBBS/MD | USMLE/NEET Preparation | 2026", sSub)]]
ct = Table(cover_title, colWidths=[W])
ct.setStyle(TableStyle([
    ("BACKGROUND",    (0,0), (-1,-1), C_DARK_BLUE),
    ("TOPPADDING",    (0,0), (-1,-1), 14),
    ("BOTTOMPADDING", (0,0), (-1,-1), 14),
    ("LEFTPADDING",   (0,0), (-1,-1), 10),
    ("RIGHTPADDING",  (0,0), (-1,-1), 10),
    ("ROUNDEDCORNERS", [6]),
]))
story.append(ct)
story.append(sp(8))

# ═══════════════════════════════════════════════════════════════════════════════
# SECTION 1: CARDIOVASCULAR DRUGS
# ═══════════════════════════════════════════════════════════════════════════════
story.append(section_banner("1.  CARDIOVASCULAR DRUGS", C_MED_BLUE))
story.append(sp(6))

# 1A – ABCDs of HTN
story.append(Paragraph("A.  Antihypertensives – The 'ABCD' Rule", sH2))
story.append(tip_box("ABCDs of BP: ACE Inhibitors, Beta-blockers, CCBs, Diuretics. "
                     "Start with A for most patients; D preferred for Black/elderly patients."))
story.append(sp(4))
story.append(make_table(
    ["Letter", "Class", "Key Drugs"],
    [
        ["A", "ACE Inhibitors / ARBs", "Enalapril, Lisinopril, Losartan, Valsartan"],
        ["B", "Beta-blockers", "Metoprolol, Atenolol, Bisoprolol, Carvedilol"],
        ["C", "Calcium Channel Blockers (CCBs)", "Amlodipine, Nifedipine, Verapamil, Diltiazem"],
        ["D", "Diuretics", "Hydrochlorothiazide (HCTZ), Furosemide, Chlorthalidone"],
    ],
    [W*0.08, W*0.42, W*0.50],
    hdr_bg=C_MED_BLUE
))
story.append(sp(8))

# 1B – Antiarrhythmics
story.append(Paragraph("B.  Antiarrhythmics – Vaughan Williams Classification", sH2))
story.append(tip_box('Mnemonic: "Some Blocks Kill All Arrhythmias" = Na+ block, Beta block, K+ block, All (Ca2+) block'))
story.append(sp(4))
story.append(make_table(
    ["Class", "Mechanism", "Key Drugs", "Clinical Use"],
    [
        ["Ia", "Na+ block (↑APD)", "Quinidine, Procainamide\n\"Queen Proclaims\"", "AF, VT (caution)"],
        ["Ib", "Na+ block (↓APD)", "Lidocaine, Mexiletine", "Post-MI VT"],
        ["Ic", "Na+ block (no APD change)", "Flecainide, Propafenone", "Avoid structural heart disease"],
        ["II",  "Beta-blockade", "Metoprolol, Esmolol, Propranolol", "SVT, rate control"],
        ["III", "K+ block (↑APD)", "Amiodarone, Sotalol\n\"Am I Sore?\"", "AF, VF, VT"],
        ["IV",  "Ca2+ block", "Verapamil, Diltiazem", "SVT, rate control"],
    ],
    [W*0.08, W*0.28, W*0.34, W*0.30],
    hdr_bg=C_TEAL, alt_bg=C_LIGHT_TEAL
))
story.append(sp(8))

# 1C – Heart Failure
story.append(Paragraph("C.  Heart Failure Drugs", sH2))
story.append(make_table(
    ["Drug Class", "Examples", "Benefit"],
    [
        ["ACE Inhibitors / ARBs", "Enalapril, Lisinopril, Losartan", "Reduce mortality ✔"],
        ["Beta-blockers", "Carvedilol, Metoprolol succinate, Bisoprolol", "Reduce mortality ✔"],
        ["ARNI (Sacubitril/Valsartan)", "Entresto", "Best new agent – reduce mortality ✔"],
        ["Diuretics", "Furosemide, HCTZ, Spironolactone", "Symptom relief; Spirono → mortality ↓"],
        ["Digoxin", "Digoxin", "Symptom relief + rate control (AF)"],
        ["SGLT2 Inhibitors", "Empagliflozin, Dapagliflozin", "Reduce hospitalisation + mortality ✔"],
    ],
    [W*0.30, W*0.40, W*0.30],
    hdr_bg=C_MED_BLUE
))
story.append(sp(8))

# 1D – Lipid-lowering
story.append(Paragraph("D.  Lipid-Lowering Drugs – Mnemonic: 'SFF-NEE'", sH2))
story.append(make_table(
    ["Letter", "Class", "Examples", "Primary Target"],
    [
        ["S", "Statins (HMG-CoA reductase inhibitors)", "Atorvastatin, Rosuvastatin, Simvastatin", "↓ LDL (1st line)"],
        ["F", "Fibrates", "Fenofibrate, Gemfibrozil", "↓ TG"],
        ["F", "Fish Oil (Omega-3)", "Icosapent ethyl (Vascepa)", "↓ TG"],
        ["N", "Niacin", "Niacin (nicotinic acid)", "↓ LDL & TG, ↑ HDL"],
        ["E", "Ezetimibe", "Ezetimibe", "↓ LDL (blocks absorption)"],
        ["E", "PCSK9 Inhibitors", "Evolocumab, Alirocumab (injectable)", "↓ LDL (severe hypercholesterolaemia)"],
    ],
    [W*0.07, W*0.32, W*0.33, W*0.28],
    hdr_bg=C_MED_BLUE
))
story.append(sp(6))
story.append(tip_box("Statins are 1st line for all patients with cardiovascular risk. Add Ezetimibe if LDL not at goal. "
                     "PCSK9i for FH or very high-risk patients."))

story.append(PageBreak())

# ═══════════════════════════════════════════════════════════════════════════════
# SECTION 2: CNS / PSYCHIATRIC DRUGS
# ═══════════════════════════════════════════════════════════════════════════════
story.append(section_banner("2.  CNS / PSYCHIATRIC DRUGS", C_PURPLE))
story.append(sp(6))

# 2A – Antidepressants
story.append(Paragraph("A.  Antidepressants – Mnemonic: 'SMART'", sH2))
story.append(tip_box("SSRIs are ALWAYS first-line. TCAs used for neuropathic pain, OCD (Clomipramine), bedwetting (Imipramine)."))
story.append(sp(4))
story.append(make_table(
    ["Letter", "Class", "Examples", "Key Feature"],
    [
        ["S", "SSRI", "Fluoxetine, Sertraline, Citalopram, Escitalopram, Paroxetine", "5-HT reuptake block; 1st line"],
        ["S", "SNRI", "Venlafaxine, Duloxetine, Desvenlafaxine", "5-HT + NE reuptake block; pain too"],
        ["M", "MAO Inhibitors", "Phenelzine, Tranylcypromine (irreversible)\nMoclobemide (reversible)", "⚠ Tyramine reaction – avoid aged cheese, wine"],
        ["A", "Atypical", "Mirtazapine (↑appetite), Bupropion (no sexual SE), Trazodone (sleep)", "Mixed/unique mechanisms"],
        ["R", "TCA (Tricyclic)", "Amitriptyline, Imipramine, Clomipramine, Nortriptyline", "NE+5-HT+anticholinergic; toxic in OD"],
    ],
    [W*0.06, W*0.18, W*0.40, W*0.36],
    hdr_bg=C_PURPLE, alt_bg=C_LIGHT_PURPLE
))
story.append(sp(8))

# 2B – Antipsychotics
story.append(Paragraph("B.  Antipsychotics", sH2))
story.append(Paragraph("<b>Typical (1st generation) – D2 Blockade</b>", sBody))
story.append(sp(2))
story.append(make_table(
    ["Potency", "Drugs", "Side Effect Profile"],
    [
        ["High potency", "Haloperidol, Fluphenazine, Trifluoperazine", "High EPS risk (Parkinsonism, Akathisia, Tardive dyskinesia)"],
        ["Low potency",  "Chlorpromazine, Thioridazine", "More sedation, anticholinergic, hypotension; Thioridazine → retinal pigmentation"],
    ],
    [W*0.20, W*0.40, W*0.40],
    hdr_bg=C_DARK_GRAY
))
story.append(sp(5))
story.append(Paragraph('<b>Atypical (2nd generation) – Mnemonic: "CORQAZ"</b>', sBody))
story.append(sp(2))
story.append(make_table(
    ["Drug", "Special Feature / Indication"],
    [
        ["Clozapine  (C)", "Best for refractory schizophrenia – MONITOR CBC (agranulocytosis risk)"],
        ["Olanzapine  (O)", "Weight gain + metabolic syndrome – avoid in diabetics"],
        ["Risperidone  (R)", "Most EPS among atypicals; prolactin elevation"],
        ["Quetiapine  (Q)", "Safest in Parkinson's psychosis / Dementia with Lewy bodies"],
        ["Aripiprazole  (A)", "Partial D2 agonist – least metabolic SE; good for bipolar adjunct"],
        ["Ziprasidone  (Z)", "QT prolongation – check ECG; take with food"],
    ],
    [W*0.28, W*0.72],
    hdr_bg=C_PURPLE, alt_bg=C_LIGHT_PURPLE
))
story.append(sp(6))
story.append(tip_box("Neuroleptic Malignant Syndrome (NMS): hyperthermia, rigidity, altered consciousness, ↑CK. "
                     "Stop antipsychotic immediately. Treat with Dantrolene + Bromocriptine."))
story.append(sp(8))

# 2C – Anxiolytics
story.append(Paragraph("C.  Anxiolytics / Sedatives", sH2))
story.append(make_table(
    ["Class", "Examples", "Mechanism", "Key Points"],
    [
        ["Benzodiazepines", "Diazepam, Lorazepam, Midazolam, Alprazolam", "GABA-A ↑ (Cl- influx)", "Dependence risk; reverse with Flumazenil"],
        ["Buspirone",       "Buspirone", "5-HT1A partial agonist", "No dependence; 2-week onset; GAD first-line"],
        ["Z-drugs",         "Zolpidem, Zaleplon, Eszopiclone", "GABA-A (BZ binding site)", "Sleep only; less dependence than BZDs"],
        ["Beta-blockers",   "Propranolol", "β-blockade → ↓ HR, tremor", "Situational/performance anxiety"],
        ["SSRIs/SNRIs",     "Escitalopram, Venlafaxine", "5-HT ± NE reuptake block", "Long-term GAD/Panic/PTSD/OCD treatment"],
    ],
    [W*0.18, W*0.26, W*0.25, W*0.31],
    hdr_bg=C_PURPLE, alt_bg=C_LIGHT_PURPLE
))
story.append(sp(4))
story.append(tip_box('Short-acting BZDs for sleep – "LETMiN": Lorazepam, Estazolam, Temazepam, Midazolam, triazolam(N).'))
story.append(sp(8))

# 2D – Antiepileptics
story.append(Paragraph("D.  Antiepileptics – by Seizure Type", sH2))
story.append(make_table(
    ["Seizure Type", "First-Line Drug(s)", "Notes"],
    [
        ["Generalized tonic-clonic (GTC)", "Valproate, Levetiracetam, Lamotrigine", "VPA broad-spectrum but teratogenic"],
        ["Absence (petit mal)",            "Ethosuximide (1st line), Valproate",    "Ethosuximide: pure absence only"],
        ["Focal / Partial seizures",       "Carbamazepine, Levetiracetam, Oxcarbazepine", "Carbamazepine: strong CYP inducer"],
        ["Myoclonic",                      "Valproate, Levetiracetam, Clonazepam", "Avoid Carbamazepine (worsens myoclonus)"],
        ["Status epilepticus",             "Lorazepam IV → Fosphenytoin → Phenobarbital → Propofol", "ABCs + thiamine first"],
        ["Trigeminal neuralgia",           "Carbamazepine (1st line)", "Not a seizure but uses AED"],
    ],
    [W*0.28, W*0.40, W*0.32],
    hdr_bg=C_TEAL, alt_bg=C_LIGHT_TEAL
))
story.append(sp(4))
story.append(tip_box('"VPA does everything" – Valproate is broad-spectrum (GTC, Absence, Myoclonic, Bipolar, Migraine prophylaxis) '
                     'BUT teratogenic (spina bifida). Avoid in women of childbearing age.'))
story.append(sp(8))

# 2E – Parkinson's
story.append(Paragraph("E.  Parkinson's Disease Drugs – Mnemonic: 'ACDS + COMT'", sH2))
story.append(make_table(
    ["Drug / Class", "Examples", "Mechanism", "Notes"],
    [
        ["A – Amantadine",       "Amantadine",                  "NMDA antagonist; ↑DA release",           "Also treats drug-induced dyskinesias"],
        ["C – Carbidopa/Levodopa","Sinemet (Carbidopa + Levodopa)","DA precursor; Carbidopa prevents peripheral conversion","Gold standard; motor fluctuations with long use"],
        ["D – DA Agonists",      "Ropinirole, Pramipexole, Rotigotine","Direct D2/D3 agonist",            "Younger patients; compulsive behaviour SE"],
        ["S – Selegiline",       "Selegiline, Rasagiline",      "MAO-B inhibitor → ↑DA",                 "Mild disease; possibly neuroprotective"],
        ["COMT inhibitors",      "Entacapone, Tolcapone",       "Block COMT → prolong levodopa effect",  "Tolcapone: hepatotoxicity – monitor LFTs"],
        ["Anticholinergics",     "Trihexyphenidyl, Benztropine","Block muscarinic receptors",             "Tremor only; avoid in elderly (confusion)"],
    ],
    [W*0.20, W*0.24, W*0.28, W*0.28],
    hdr_bg=C_TEAL, alt_bg=C_LIGHT_TEAL
))

story.append(PageBreak())

# ═══════════════════════════════════════════════════════════════════════════════
# SECTION 3: ANTIBIOTICS / ANTI-INFECTIVES
# ═══════════════════════════════════════════════════════════════════════════════
story.append(section_banner("3.  ANTIBIOTICS / ANTI-INFECTIVES", C_GREEN))
story.append(sp(6))

# 3A – Classes overview
story.append(Paragraph("A.  Antibiotic Classes – Mnemonic: 'PLATES + MVC'", sH2))
story.append(make_table(
    ["Letter", "Class", "Key Drugs", "Primary Coverage"],
    [
        ["P", "Penicillins", "Amoxicillin, Ampicillin, Nafcillin, Pip-Tazobactam", "Gram+/- (broad with pip-tazo)"],
        ["L", "Lincosamides", "Clindamycin", "Gram+, Anaerobes (above & below diaphragm)"],
        ["A", "Aminoglycosides", "Gentamicin, Amikacin, Tobramycin", "Aerobic Gram- rods (synergy with cell-wall agents)"],
        ["T", "Tetracyclines", "Doxycycline, Minocycline, Tigecycline", "Atypicals, Rickettsia, Brucella, Chlamydia"],
        ["E", "Macrolides", "Azithromycin, Clarithromycin, Erythromycin", "Atypicals, Strep, H. pylori (clarithro)"],
        ["S", "Sulfonamides/TMP-SMX", "Trimethoprim-Sulfamethoxazole", "UTI, PCP, Nocardia, community MRSA"],
        ["M", "Metronidazole", "Metronidazole (Flagyl)", "Anaerobes, C. diff (oral), Protozoa (Giardia, Trichomonas)"],
        ["V", "Vancomycin", "Vancomycin", "MRSA, C. diff (oral), Gram+ only"],
        ["C", "Carbapenems", "Meropenem, Imipenem, Ertapenem", "Broadest spectrum; covers ESBL, anaerobes"],
    ],
    [W*0.06, W*0.22, W*0.34, W*0.38],
    hdr_bg=C_GREEN, alt_bg=C_LIGHT_GREEN
))
story.append(sp(8))

# 3B – Coverage cheat sheet
story.append(Paragraph("B.  Coverage Cheat Sheet", sH2))
cov_data = [
    [Paragraph("<b>Organism / Scenario</b>", S("h", fontName="Helvetica-Bold", fontSize=8.5, textColor=C_WHITE, alignment=TA_CENTER)),
     Paragraph("<b>Go-to Antibiotic(s)</b>", S("h", fontName="Helvetica-Bold", fontSize=8.5, textColor=C_WHITE, alignment=TA_CENTER))],
    ["Gram+ cocci (MSSA)", "Nafcillin/Oxacillin; Cefazolin (surgical prophylaxis)"],
    ["Gram+ cocci (MRSA)", "Vancomycin (IV), Linezolid (oral), Daptomycin, TMP-SMX (CA-MRSA)"],
    ["Gram- rods (E. coli, Klebsiella)", "Cephalosporins 3rd/4th gen, Fluoroquinolones, Aminoglycosides"],
    ["Pseudomonas aeruginosa", "Pip-Tazo, Cefepime (4th), Meropenem, Ciprofloxacin, Aminoglycosides"],
    ["Atypicals (Mycoplasma, Legionella, Chlamydia)", "Azithromycin, Doxycycline, Fluoroquinolones (levofloxacin)"],
    ["Anaerobes – above diaphragm", "Clindamycin, Amoxicillin-clavulanate"],
    ["Anaerobes – below diaphragm", "Metronidazole, Pip-Tazo, Meropenem"],
    ["C. difficile", "Vancomycin PO (1st line) or Fidaxomicin; Metronidazole (mild only)"],
    ["Meningitis (community)", "Ceftriaxone + Vancomycin (+ Ampicillin if >50 yrs for Listeria)"],
    ["PCP (Pneumocystis jirovecii)", "TMP-SMX (+ steroids if PaO2 <70 mmHg)"],
]
cov_t = Table(cov_data, colWidths=[W*0.42, W*0.58])
cov_t.setStyle(TableStyle([
    ("BACKGROUND",    (0,0), (-1,0), C_GREEN),
    ("GRID",          (0,0), (-1,-1), 0.4, C_GREEN),
    ("TOPPADDING",    (0,0), (-1,-1), 3),
    ("BOTTOMPADDING", (0,0), (-1,-1), 3),
    ("LEFTPADDING",   (0,0), (-1,-1), 5),
    ("VALIGN",        (0,0), (-1,-1), "MIDDLE"),
    ("ROWBACKGROUNDS",(0,1), (-1,-1), [C_WHITE, C_LIGHT_GREEN]),
    ("FONTNAME",      (0,1), (-1,-1), "Helvetica"),
    ("FONTSIZE",      (0,1), (-1,-1), 8.2),
]))
story.append(cov_t)
story.append(sp(8))

# 3C – Cephalosporins by generation
story.append(Paragraph("C.  Cephalosporins by Generation", sH2))
story.append(tip_box("Each generation ↑ Gram(-) coverage but ↓ Gram(+) activity. "
                     "5th gen (Ceftaroline) is the only cephalosporin active against MRSA."))
story.append(sp(4))
story.append(make_table(
    ["Generation", "Memory Hook", "Key Drugs", "Clinical Use"],
    [
        ["1st", "Gram+ King", "Cefazolin (IV), Cephalexin (PO)", "Surgical prophylaxis, skin/soft tissue"],
        ["2nd", "H. flu added + anaerobes", "Cefuroxime, Cefoxitin, Cefotetan", "Respiratory, pelvic infections"],
        ["3rd", "Gram- power", "Ceftriaxone, Cefotaxime, Ceftazidime*", "Meningitis, gonorrhoea, sepsis (*Pseudomonas)"],
        ["4th", "Pseudomonas added", "Cefepime", "Severe Gram- / febrile neutropenia"],
        ["5th", "MRSA buster", "Ceftaroline", "MRSA skin infections, CAP"],
    ],
    [W*0.13, W*0.27, W*0.30, W*0.30],
    hdr_bg=C_GREEN, alt_bg=C_LIGHT_GREEN
))
story.append(sp(8))

# 3D – Side effects
story.append(Paragraph("D.  Key Antibiotic Side Effects – Must Know!", sH2))
story.append(make_table(
    ["Drug", "Classic Side Effect / Toxicity"],
    [
        ["Aminoglycosides (Gentamicin, Amikacin)", "Nephrotoxicity + Ototoxicity (monitor levels)"],
        ["Vancomycin",                  '"Red Man Syndrome" (slow infusion rate) + Nephrotoxicity (with aminoglycosides)'],
        ["Metronidazole",               "Metallic taste; disulfiram-like reaction with alcohol; peripheral neuropathy"],
        ["Fluoroquinolones",            "Tendon rupture (Achilles), QT prolongation, avoid in children/pregnancy"],
        ["Tetracyclines",               "Photosensitivity, teeth discolouration (children), avoid in pregnancy"],
        ["Chloramphenicol",             '"Gray Baby Syndrome" (neonates); aplastic anemia'],
        ["Clindamycin",                 "C. difficile pseudomembranous colitis (highest risk)"],
        ["Rifampin",                    "Orange urine/sweat/tears; potent CYP450 inducer (many drug interactions)"],
        ["Isoniazid (INH)",             "Peripheral neuropathy (give B6/pyridoxine), hepatotoxicity, lupus-like"],
        ["Sulfonamides (TMP-SMX)",      "Stevens-Johnson syndrome, kernicterus (neonates), folate deficiency"],
    ],
    [W*0.40, W*0.60],
    hdr_bg=C_RED, alt_bg=C_LIGHT_RED
))

story.append(PageBreak())

# ═══════════════════════════════════════════════════════════════════════════════
# SECTION 4: QUICK MNEMONICS SUMMARY PAGE
# ═══════════════════════════════════════════════════════════════════════════════
story.append(section_banner("4.  QUICK MNEMONICS SUMMARY", C_ORANGE))
story.append(sp(6))

story.append(make_table(
    ["Mnemonic", "Meaning", "Category"],
    [
        ["ABCDs of BP",        "ACE Inhibitors → Beta-blockers → CCBs → Diuretics",                "Antihypertensives"],
        ["Some Blocks Kill All", "Na+ / Beta / K+ / Ca2+ channel blockers",                         "Antiarrhythmics"],
        ["SMART",              "SSRI → SNRI → MAOI → Atypical → TCA (Tricyclic)",                  "Antidepressants"],
        ["CORQAZ",             "Clozapine, Olanzapine, Risperidone, Quetiapine, Aripiprazole, Ziprasidone", "Atypical Antipsychotics"],
        ["LETMiN",             "Lorazepam, Estazolam, Temazepam, Midazolam, triazolam(N) – short-acting BZDs", "Anxiolytics / Sleep"],
        ["VPA does everything", "Valproate = GTC + Absence + Myoclonic + Bipolar + Migraine prophylaxis", "Antiepileptics"],
        ["ACDS + COMT",        "Amantadine → Carbidopa/Levodopa → DA Agonists → Selegiline + COMT inhibitors", "Parkinson's"],
        ["PLATES + MVC",       "Penicillins, Lincosamides, Aminoglycosides, Tetracyclines, Macrolides, Sulfonamides + Metronidazole, Vancomycin, Carbapenems", "Antibiotics"],
        ["SFF-NEE",            "Statins, Fibrates, Fish Oil, Niacin, Ezetimibe, PCSK9 Inhibitors",  "Lipid-lowering"],
        ["1-2-3-4-5 Ceph",     "Each generation ↑ Gram(-), ↓ Gram(+); 5th gen covers MRSA",        "Cephalosporins"],
    ],
    [W*0.20, W*0.52, W*0.28],
    hdr_bg=C_ORANGE, alt_bg=C_LIGHT_ORANGE
))
story.append(sp(8))

# High-yield exam boxes
story.append(Paragraph("High-Yield Exam Facts", sH2))
exam_facts = [
    ["⚠ Drug to AVOID in absence seizures:", "Carbamazepine (worsens)"],
    ["⚠ Only cephalosporin covering MRSA:",  "Ceftaroline (5th gen)"],
    ["⚠ Antidepressant safe in pregnancy:",  "Sertraline (SSRIs preferred)"],
    ["⚠ Antipsychotic requiring CBC monitoring:", "Clozapine (agranulocytosis)"],
    ["⚠ Antibiotic + alcohol = vomiting:",   "Metronidazole (disulfiram-like)"],
    ["⚠ DON'T give fluoroquinolones to:",    "Children < 18, pregnant women (tendon/cartilage damage)"],
    ["⚠ Best drug for status epilepticus:",  "Lorazepam IV (first) → Fosphenytoin → Phenobarbital"],
    ["⚠ Heart failure + best mortality benefit:", "Sacubitril/Valsartan (ARNI) > ACEi/ARB"],
    ["⚠ First-line for community-acquired MRSA:", "TMP-SMX (oral); Vancomycin IV for severe"],
    ["⚠ Valproate contraindication:",        "Pregnancy (spina bifida); Liver disease"],
]
ef_t = Table(exam_facts, colWidths=[W*0.50, W*0.50])
ef_t.setStyle(TableStyle([
    ("GRID",          (0,0), (-1,-1), 0.4, C_ORANGE),
    ("TOPPADDING",    (0,0), (-1,-1), 4),
    ("BOTTOMPADDING", (0,0), (-1,-1), 4),
    ("LEFTPADDING",   (0,0), (-1,-1), 6),
    ("VALIGN",        (0,0), (-1,-1), "MIDDLE"),
    ("ROWBACKGROUNDS",(0,0), (-1,-1), [C_LIGHT_YELLOW, C_WHITE]),
    ("FONTNAME",      (0,0), (-1,-1), "Helvetica"),
    ("FONTSIZE",      (0,0), (-1,-1), 8.5),
    ("FONTNAME",      (0,0), (0,-1),  "Helvetica-Bold"),
    ("TEXTCOLOR",     (0,0), (0,-1),  C_RED),
]))
story.append(ef_t)

story.append(sp(12))

# Footer
footer_data = [[
    Paragraph("Pharmacology Drug Classification Study Guide  |  MBBS/MD / USMLE/NEET Edition  |  2026",
              S("ft", fontName="Helvetica", fontSize=7.5, textColor=C_WHITE, alignment=TA_CENTER))
]]
ft = Table(footer_data, colWidths=[W])
ft.setStyle(TableStyle([
    ("BACKGROUND", (0,0), (-1,-1), C_DARK_BLUE),
    ("TOPPADDING",    (0,0), (-1,-1), 6),
    ("BOTTOMPADDING", (0,0), (-1,-1), 6),
]))
story.append(ft)

# ── Build ──────────────────────────────────────────────────────────────────────
doc.build(story)
print("PDF created successfully!")