Clinician's Pocket Drug Reference 2008

Procarbazine 175transmission modulator, antinociceptive, antiseizure effect; mechanism ?; related togabapentin Dose: Neuropathic pain: 50 mg PO tid, ↑ to 300 mg/d w/in 1 wk basedon response, 300 mg/d max; Postherpetic neuralgia: 75–150 mg bid, or 50–100mg tid; start 75 mg bid or 50 mg tid; ↑ to 300 mg/d w/in 1 wk PRN; if pain persistsafter 2–4 wk, ↑ to 600 mg/d; Epilepsy: Start 150 mg/d (75 mg bid or 50 mg tid)may ↑ to max 600 mg/d; ↓ w/ renal insuffic; w/ or w/o food Caution: [X, –] w/significant renal impair (see insert), w/elderly & severe CHF avoid abrupt D/CContra: PRG Disp: Caps 25, 50, 75, 100, 150, 200, 225, 300 mg SE: Dizziness,drowsiness, xerostomia, edema, blurred vision, wgt gain, difficulty concentratingNotes: w/ D/C, taper over at least 1 wkProbenecid (Benemid, others) Uses: *Prevent gout & hyperuricemia;prolongs levels of PCNs & cephalosporins* Action: Urocosuric, renal tubularblocker of organic anions Dose: Adults. Gout: 250 mg bid × 1 wk, then 0.5 g PObid; can ↑ by 500 mg/mo up to 2–3 g/d. Antibiotic effect: 1–2 g PO 30 min beforedose Peds >2 y. 25 mg/kg, then 40 mg/kg/d PO ÷ qid Caution: [B, ?] Contra:High-dose ASA, moderate–severe renal impair, age 50%,then 1–4 mg/min. Chronic dosing: 50 mg/kg/d PO in ÷ doses q4–6h; RecurrentVF/VT: 20–50 mg/min IV; max total 17 mg/kg. Others: 20 mg/min IV until onethese: arrhythmia stopped, hypotension, QRS widens > 50%, total 17 mg/kg; then1–4 mg/min (ECC 2005) Peds. Chronic maint: 15–50 mg/kg/24 h PO ÷ q3–6h; ↓ inrenal/hepatic impair Caution: [C, +] Contra: Complete heart block, 2nd- or 3rddegreeheart block w/o pacemaker, torsades de pointes, SLE Disp: Tabs & caps 250,500 mg; SR tabs 500, 750, 1000 mg; inj 100, 500 mg/mL SE: ↓ BP, lupus-likesynd, GI upset, taste perversion, arrhythmias, tachycardia, heart block, angioneuroticedema, blood dyscrasias Notes: Levels: Trough: just before next dose: Therapeutic:4–10 mcg/mL; NAPA+ procaine 5–30 mcg/mL Toxic >10 mcg/mL; NAPA+procaine > 30 mcg/mL; 1 ⁄2 life: procaine 3–5 h, NAPA 6–10 hProcarbazine (Matulane) WARNING: Highly toxic; handle w/ careUses: *Hodgkin Dz,* NHL, brain & lung tumors Action: Alkylating agent; ↓DNA & RNA synth Dose: Per protocol Caution: [D, ?] W/ EtOH ingestion Contra:Inadequate BM reserve Disp: Caps 50 mg SE: ↓ BM, hemolytic rxns (w/G6PD deficiency), N/V/D; disulfiram-like Rxn; cutaneous & constitutional Sxs,myalgia, arthralgia, CNS effects, azoospermia, cessation of menses