PACLITAXEL (ABRAXANE, TAXOL, GENERIC)
WARNING: Administration only by physician experienced in chemotherapy; fatal anaphylaxis and hypersens possible; severe myelosuppression possible.
USES: *Ovarian & breast cancer, Kaposi sarcoma, non-small cell lung cancer.*
ACTIONS: Mitotic spindle poison; promotes microtubule assembly & stabilization against depolymerization.
DOSE: Per protocols; use glass or polyolefin containers (eg, nitroglycerin tubing set); PVC sets leach plasticizer; ↓ in hepatic failure.
W/P: [D, −].
CI: Neutropenia ANC <1,500 cells/mm3, <1,000 cells/mm3 in w/ AIDS-related Karposi’s syndrome; solid tumors, component allergy.
DISP: Inj 6 mg/mL, vial 5, 16.7, 25, 50 mL; (Abraxane) 100 mg/vial.
SE: ↓ BM, peripheral neuropathy, transient ileus, myalgia, ↓ HR, ↓ BP, mucositis, N/V/diarrhea, fever, rash, headache, phlebitis; hematologic tox schedule dependent; leukopenia dose limiting by 24-hr Inf; neurotox limited w/ short (1–3 hr) Inf; allergic reactions (dyspnea, ↓ BP, urticaria, rash).
NOTES: Maintain hydration; allergic reaction usually w/in 10 min of Inf; minimize w/ corticosteroid, antihistamine pretreatment.
PALONOSETRON (ALOXI)
USES: *Prevent acute & delayed N/V w/ emetogenic chemotherapy; prevent postoperative N/V up to 24 hr.*
ACTIONS: 5-HT3-receptor antagonist.
DOSE:
Adults: Chemotherapy: 0.25 mg IV 30 min prechemo; 0.5 mg PO 1 hr prechemo w/o regard to food. Postoperative N/V: 0.075 mg immediately before induction.
Peds: 1 mo–17yr 20 μg/kg (max. 1.5 mg) × 1 IV over 15 min, 30 min prechemo.
W/P: [B, ?] May ↑ QTc interval.
CI: Component allergy.
DISP: 0.05 mg/mL (1.5 & 5 mL vials); 0.5 mg caps.
SE: HA, constipation, dizziness, abdominal pain, anxiety.
PAMIDRONATE (GENERIC)
USES: *Hypercalcemia of malignancy, Paget disease, palliate symptomatic osteolytic mets of multiple myeloma and breast cancer.*
ACTIONS: Bisphosphonate; ↓ nl & abnormal bone resorption.
DOSE: Hypercalcemia: 60–90 mg IV over 2–24 hr or 90 mg IV over 24 hr if severe; may repeat in 7 days. Paget disease: 30 mg/d IV slow Inf over 4 hr × 3 days. Osteolytic bone mets in myeloma: 90 mg IV over 4 hr qmo. Osteolytic bone mets breast cancer: 90 mg IV over 2 hr q3–4wk; 90 mg/max. single dose.
W/P: [D, ?/−] Avoid invasive dental procedures w/ use.
CI: Bisphosphonate sensitivity.
DISP: Inj 30, 60, 90 mg.
SE: Fever, malaise, convulsions, Inj site reaction, uveitis, fluid overload, HTN, abdominal pain, N/V, constipation, UTI, bone pain, ↓ K+, ↓ Ca2+, ↓ Mg2+, hypophosphatemia; jaw osteonecrosis (mostly cancer pts; avoid dental work), renal tox.
NOTES: Perform dental exam pretherapy; follow Cr, hold dose if Cr ↑ by 0.5 mg/dL w/ nl baseline or by 1 mg/dL w/ abnormal baseline; restart when Cr returns w/in 10% of baseline; may ↑ atypical subtrochanteric femur fractures.
PAPAVERINE; PAPAVERINE/PHENTOLAMINE (“BIMIX”); PAPAVERINE/PHENTOLAMINE/PROSTAGLANDIN E1 (“TRIMIX”)
(Note: These medications are not FDA approved for this use. These medications are prepared by compounding pharmacies.)
USES: Erectile dysdunction.
ACTIONS: Prostaglandin E1: Vasodilator, relaxes smooth muscle of corpus cavernosa; papaverine: smooth muscle relaxation w/ vasodilatation; phentolamine blocks α-adrenergic receptors, results in vasodilation.
DOSE: Based on formulation, typical starting volumes of 0.1–0.5 mL and titrated in the office; self-administered using insulin syringe with a 26–30G 1/2-inch needle through the lateral shaft of the mod penis into one corporeal body; erection should occur in a few minutes.
W/P: [n/a, n/a].
CI: No official information, probably similar to intracorporeal alprostadil: ↑ Priapism risk (especially sickle cell, myeloma, leukemia), penile deformities/urethral stricture/implants; men in whom sex inadvisable; component hypersensitivity.
DISP: Based on compounding pharmacy; reported concentrations: Papaverine 5–30 mg/mL; BiMix (papaverine 5.88–30 mg and phentolamine 1–4 mg); TriMix (papaverine 5–30 mg/mL, phentolamine 0.1–5 mg/mL, prostaglandin E1 5–40 μg/mL).
SE: Penile pain, penile nodule formation, transient increases in LFTs, and hematoma priapism.
NOTES: Titrate dose in office.
PASIREOTIDE (SIGNIFOR)
USES: *Cushing disease where pituitary surgery not an option*
ACTIONS: Somatostatin analogue inhibitor ACTH secretion.
DOSE:
Adults: 0.6–0.9 mg SQ 2×/d; titrate on response/tolerability; hepatic impairment (Child-Pugh B): 0.3–0.6 mg SQ twice daily, (Child-Pugh C): avoid.
W/P: [C, −] w/ Risk for ↓ HR or ↑ QT; w/ drugs that ↓ HR, ↑ QT, cyclosporine, bromocriptine.
CI: None.
DISP: Inj single-dose 0.3, 0.6, 0.9 mg/mL.
SE: N/V/diarrhea, hyperglycemia, headache, abdominal pain, cholelithiasis, fatigue, DM, hypocortisolism, ↓ HR, QT prolongation, ↑ glucose, ↑ LFTs, ↓ pituitary hormones, Inj site reaction, edema, alopecia, asthenia, myalgia, arthralgia.
NOTES: Prior to and periodically (see label), check TSH/T4 , HbA1c, LFTs, ECG, gallbladder US.
PAZOPANIB (VOTRIENT)
WARNING: Severe and fatal hepatotoxicity has been observed in clinical trials. Monitor hepatic function and interrupt, reduce, or discontinue dosing.
USES: *Advanced RCC; metastatic soft-tissue sarcoma after chemotherapy.*
ACTIONS: Tyrosine kinase inhibitor.
DOSE: 800 mg PO once daily, ↓ to 200 mg daily if moderate hepatic impairment, not rec in severe hepatic disease (bili >3 × ULN).
W/P: [D, −] Avoid w/ CYP3A4 inducers/inhibitor and QTc prolonging drugs, all SSRI; follow thyroid function tests; risk of thrombotic microangiopathy (TMA), including thrombotic thrombocytopenic purpura (TTP) and HUS; simvastatin increases the risk of ALT elevations.
CI: Severe hepatic disease.
DISP: 200-mg tablet.
SE: ↑ BP, N/V/diarrhea, GI perf, anorexia, hair depigmentation, ↓ WBC, ↓ plt, ↑ bleeding, ↑ AST/ALT/bili, ↓ Na, CP, ↑ QTc; reversible posterior leukoencephalopathy syndrome; proteinuria (hold w/ >3 g protein/24 h).
NOTES: Hold for surgical procedures. Take 1 hr ac or 2 hr pc.
PEGFILGRASTIM (NEULASTA)
USES: *↓ Frequency of infection in pts w/ nonmyeloid malignancies receiving myelosuppressive anti-cancer drugs that cause febrile neutropenia.*
ACTIONS: Granulocyte and macrophage-stimulating factor.
DOSE:
Adults: 6 mg SQ × 1/chemotherapy cycle.
W/P: [C, M] w/ Sickle cell.
CI: Allergy to E. coli-derived proteins or filgrastim.
DISP: Syringes: 6 mg/0.6 mL.
SE: Splenic rupture, headache, fever, weakness, fatigue, dizziness, insomnia, edema, N/V/diarrhea, stomatitis, anorexia, constipation, taste perversion, dyspepsia, abdominal pain, granulocytopenia, neutropenic fever, ↑ LFTs & uric acid, arthralgia, myalgia, bone pain, ARDS, alopecia, worsen sickle cell disease.
NOTES: Never give between 14 days before & 24 hr after dose of cytotoxic chemotherapy.
PENCICLOVIR (DENAVIR)
USES: *Herpes simplex (herpes labialis/cold sores).*
ACTIONS: Competitive inhibitor of DNA polymerase.
DOSE: Apply at 1st sign of lesions, then q2h while awake × 4 days.
W/P: [B, ?/−].
CI: Allergy, previous reaction to famciclovir.
DISP: Cream 1%.
SE: Erythema, headache.
NOTES: Do not apply to mucous membranes.
PENICILLIN G, AQUEOUS (POTASSIUM OR SODIUM) (PFIZERPEN, PENTIDS)
USES: *Bacteremia, endocarditis, pericarditis, resp tract infections, meningitis, neurosyphilis, SSSI.*
ACTIONS: Bactericidal; ↓ cell wall synth. Spectrum: Most gram(+) (not staphylococci), streptococci, N. meningitidis, syphilis, clostridia, & anaerobes (not Bacteroides).
DOSE:
Adults: Based on indication range 0.6–24 MU/d in ÷ doses q4h.
Peds: Newborns < wk: 25,000–50,000 U/ kg/dose IV q12h. Infants 1 wk–<1 mo: 25,000–50,000 U/kg/dose IV q8h. Children: 100,000–400,000 U/kg/24h IV ÷ q4h; ↓ in renal impairment.
W/P: [B, M].
CI: Allergy.
DISP: Powder for Inj.
SE: Allergic reactions; interstitial nephritis, diarrhea, seizures.
NOTES: Contains 1.7 mEq of K+/MU.
PENICILLIN V (PEN-VEE K, VEETIDS, OTHERS)
USES: Susceptible streptococcal infections, otitis media, URIs, skin/soft-tissue infections (PCN-sensitive staphylococci).
ACTIONS: Bactericidal; ↓ cell wall synth. Spectrum: Most gram(+), including streptococci.
DOSE:
Adults: 250–500 mg PO q6h, q8h, q12h.
Peds: 25–50 mg/kg/24 h PO in 3–4 ÷ dose above the age of 12 yr, dose can be standardized vs. Wt based; ↓ in renal impairment; take on empty stomach.
W/P: [B, M].
CI: Allergy.
DISP: Tabs 125, 250, 500 mg; susp 125, 250 mg/5 mL.
SE: GI upset, interstitial nephritis, anaphylaxis, convulsions.
NOTES: A well-tolerated oral PCN; 250 mg = 400,000 U of PCN G.
PENICILLIN G BENZATHINE (BICILLIN)
USES: *Single-dose regimen for streptococcal pharyngitis, rheumatic fever, glomerulonephritis prophylaxis, & syphilis.*
ACTIONS: Bactericidal; ↓ cell wall synth. Spectrum: See Penicillin G.
DOSE:
Adults: 1.2–2.4 MU deep IM Inj q2–4wk.
Peds: 50,000 U/kg/dose, 2.4 MU/dose max.; deep IM Inj q2–4 wk.
W/P: [B, M].
CI: Allergy.
DISP: Inj 300,000, 600,000 U/mL; Bicillin L-A benzathine salt only; Bicillin C-R combo of benzathine & procaine (300,000 U procaine w/ 300,000 U benzathine/mL or 900,000 U benzathine w/ 300,000 U procaine/2 mL).
SE: Inj site pain, acute interstitial nephritis, anaphylaxis.
NOTES: IM use only; sustained action, w/ levels up to 4 wk; drug of choice for noncongenital syphilis.
PENICILLIN G PROCAINE (WYCILLIN, OTHERS)
USES: *Infections of resp tract, skin/soft tissue, scarlet fever, syphilis.*
ACTIONS: Bactericidal; ↓ cell wall synth. Spectrum: PCN G-sensitive organisms that respond to low, persistent serum levels.
DOSE:
Adults: 0.6–4.8 MU/d in ÷ doses q12–24h; give probenecid at least 30 min prior to PCN to prolong action.
Peds: 25,000–50,000 U/kg/d IM ÷ daily–BID.
W/P: [B, M].
CI: Allergy.
DISP: Inj 300,000, 500,000, 600,000 U/mL.
SE: Pain at Inj site, interstitial nephritis, anaphylaxis.
NOTES: LA parenteral PCN; levels up to 15 hr.
PENTAZOCINE (TALWIN, TALWIN COMPOUND, TALWIN NX) [C-IV]
WARNING: Oral use only; severe and potentially lethal reactions from misuse by Inj.
USES: *Mod–severe pain.*
ACTIONS: Partial narcotic agonist–antagonist; combination with other pain relief agents (see Disp).
DOSE:
Adults: 30 mg IM or IV; 50–100 mg PO q3–4h PRN.
Peds: 5–8 yr: 15 mg IM q4h PRN. 9–14 yr: 30 mg IM q4h PRN; ↓ in renal/hepatic impairment.
W/P: [C (1st tri, D w/ prolonged use/high dose near term), +/−].
CI: Allergy, ↑ ICP (unless ventilated).
DISP: Talwin Compound tab 12.5 mg + 325 mg aspirin; Talwin NX 50 mg + 0.5 mg naloxone; Talwin Inj 30 mg/mL.
SE: Considerable dysphoria; drowsiness, GI upset, xerostomia, seizures.
NOTES: 30–60 mg IM = 10 mg of morphine IM; Talwin NX has naloxone to curb abuse by nonoral route.
PENTOSAN POLYSULFATE SODIUM (ELMIRON)
USES: *Relieve pain/discomfort w/ interstitial cystitis.*
ACTIONS: Bladder wall buffer.
DOSE: 100 mg PO TID; on empty stomach w/ H2O 1 hr ac or 2 hr pc.
W/P: [B, ?/−].
CI: Hypersensitivity to pentosan or related compounds (LMWH, heparin).
DISP: Caps 100 mg.
SE: Alopecia, N/diarrhea, headache, ↑ LFTs, anticoagulant effects, ↓ plts, rectal bleed.
NOTES: Reassess after 3 mo; related to LMWH, heparin; role for hemorrhagic cystitis suggested.
PERMETHRIN (ELIMITE, NIX, GENERIC [OTC])
USES: *Treat lice/scabies.*
ACTIONS: Pediculicide.
DOSE:
Adults & Peds: >2 yr: Lice: Saturate hair & scalp; allow 10 min before rinsing. Scabies: Apply cream head to toe; leave for 8–14 hr, wash w/ H2O.
W/P: [B, ?/−].
CI: Allergy >2 mo.
DISP: Topical lotion 1%; cream 5%.
SE: Local irritation.
NOTES: Sprays available (Rid, A200, Nix) to disinfect clothing, bedding, combs, & brushes; lotion not OK in peds <2 mo; may repeat after 7 days.
PHENAZOPYRIDINE (PYRIDIUM, GENERIC) (AZO, MANY OTHER OTC FORMS)
USES: *Relief of pain, burning, urgency, frequency, and other discomforts d/t irritation of the lower urinary tract mucosa caused by infection, trauma, surgery, endoscopic procedures, or the passage of sounds or catheters. *
ACTIONS: Anesthetic on urinary tract mucosa.
DOSE:
Adults: 100–200 mg PO TID; 2 days max. w/ antibiotics for UTI; ↓ w/ renal insufficiency.
W/P: [B, ?] Hepatic disease; methemoglobinemia w/ acute overdose.
CI: Renal failure, component hypersensitivity.
DISP: Tabs (Pyridium, Rx) 100, 200 mg; OTC Tabs 45, 95, 97.2, 97.5, 99.5 mg.
SE: GI disturbances, red-orange urine color (can stain clothing, contacts), yellow tinge to skin/sclera, rash, headache, dizziness, acute renal failure, methemoglobinemia, tinting of sclera/skin.
NOTES: Take w/ food, hydrate well. For peds phenazopyridine can be compounded with glycerin to form a suspension yielding a 10 mg/mL solution, the dose is 4 mg/kg/dose TID.
PHENYLEPHRINE, ORAL (SUDAFED, OTHERS [OTC])
WARNING: Not for use in peds <2 yr.
USES: *Nasal congestion.*
ACTIONS: α-Adrenergic agonist.
DOSE:
Adults: 10–20 mg PO q4h PRN, max. 60 mg/d.
Peds: 4–5 y: 2.5 mg q4h max. 6 doses/d; >6–12: 5 mg q4h, max. 30 mg/d ≥12: adult dosing.
W/P: [C, +/−] HTN, acute pancreatitis, hep, coronary disease, narrow-angle glaucoma, hyperthyroidism.
CI: MAOI w/in 14 days, narrow-angle glaucoma, severe ↑ BP or CAD, urinary retention.
DISP: Liq 7.5 mg/5 mL; drops: 1.25/0.8 mL, 2.5 mg/5 mL; tabs 5, 10 mg; chew tabs 10 mg; tabs once daily 10 mg; strips: 1.25, 2.5, 10 mg; many combo OTC products.
SE: Arrhythmias, HTN, headache, agitation, anxiety, tremor, palpitations; can be chemically processed into methamphetamine; products now sold behind pharmacy counter w/o prescription.
NOTES: 60 mg 4 times daily for 6 wk for retrograde ejaculation.
PIPERACILLIN/TAZOBACTAM (ZOSYN, GENERIC)
USES: *Infections of skin, bone, resp & urinary tract, abdominal, sepsis.*
ACTIONS: 4th-gen PCN plus β-lactamase inhibitor; bactericidal; ↓ cell wall synth. Spectrum: Good gram(+), excellent gram(−); anaerobes & β-lactamase producers.
DOSE:
Adults: 3.375–4.5 g IV q6h; ↓ in renal insufficiency.
W/P: [B, M].
CI: PCN or β-lactam sensitivity.
DISP: Frozen and powder for Inj: 2.25, 3.375, 4.5 g.
SE: Diarrhea, headache, insomnia, GI upset, serum sickness-like reaction, pseudomembranous colitis.
NOTES: Often used in combo w/ aminoglycoside.
PODOFILOX [PODOPHYLLIN] (PODOCON-25, CONDYLOX, CONDYLOX GEL 0.5%)
USES: *Topical Treat of benign growths (genital & perianal warts [condylomata acuminata]*, papillomas, fibromas).
ACTIONS: Direct antimitotic effect; exact mechanism unknown.
DOSE: Condylox gel & Condylox: Apply BID for 3 consecutive d/wk then hold for 4 days, may repeat 4 × 0.5 mL/d max.; Podocon-25: Use sparingly on the lesion, leave on for only 30–40 min for 1st application, then 1–4 hr on subsequent applications, thoroughly wash off; limit <5 mL or <10 cm2/Treat.
W/P: [X, ?] Immunosuppression.
CI: DM, bleeding lesions.
DISP: Podocon-25 (w/ benzoin) 15-mL bottles; Condylox gel 0.5% 35-g clear gel; Condylox soln 0.5% 35-g clear.
SE: Local reactions, sig absorption; anemias, tachycardia, paresthesias, GI upset, renal/hepatic damage.
NOTES: Podocon-25 applied by the clinician; do not dispense directly to pt.
POLYETHYLENE GLYCOL [PEG] 3350 (MIRALAX [OTC])
USES: *Occasional constipation*, constipation/dysfunctional elimination syndrome in peds.
ACTIONS: Osmotic laxative.
DOSE:
Adult: 17-g powder (1 heaping tsp) in 8 oz (1 cup) of H2O & drink; max. 14 d.
Peds: >6 mo: (Not FDA) 0.5–1.5 g/kg daily, max. dose 17 g/d.
W/P: [C, ?] Rule out bowel obst before use.
CI: GI obst, allergy to PEG.
DISP: Powder for reconstitution; bottle cap holds 17 g.
SE: Upset stomach, bloating, cramping, gas, severe diarrhea, hives.
NOTES: Can add to H2O, juice, soda, coffee, or tea.
POTASSIUM CITRATE (UROCIT-K, GENERIC)
USES: *Alkalinize urine, prevention of urinary stones (uric acid, calcium stones if hypocitraturic).*
ACTIONS: Urinary alkalinizer.
DOSE: 30–60 mEq/d based on severity of hypocitraturia. Max. 100 mEq/d.
W/P: [A, +].
CI: Severe renal impairment, dehydration, ↑ K+, peptic ulcer; w/ K+-sparing diuretics, salt substitutes.
DISP: Tabs 5, 10, 15 mEq/d.
SE: GI upset, ↓ Ca2+, ↑ K+ (more likely with renal insufficiency); metabolic alkalosis.
NOTE: Maintain high fluid intake; gastrointestinal upset is the primary SE; treatment should be avoided when the urine pH is >6.5.
POTASSIUM SUPPLEMENTS (KAON, KAOCHLOR, K-LOR, SLOW-K, MICRO-K, KLORVESS, GENERIC)
USES: *Prevention or Treat of ↓ K+* (eg, diuretic use).
ACTIONS: K+ supl.
DOSE:
Adults: 20–100 mEq/d PO ÷ 1–4×/d; IV 10–20 mEq/h, max. 40 mEq/h & 150 mEq/d (monitor K+ levels frequently and in presence of continuous ECG monitoring w/ high-dose IV).
Peds: Calculate K+ deficit; 1–3 mEq/kg/d PO ÷ 1–4×/d; IV max. dose 0.5–1 mEq/kg/× 1–2 hr.
W/P: [A, +] Renal insufficiency, use w/ NSAIDs & ACE inhibitor.
CI: ↑ K+.
DISP: PO forms see table at top of page, Inj.
SE: GI irritation; ↓ HR, ↑ K+, heart block.
NOTES: Mix powder & liq w/ beverage (unsalted tomato juice, etc.); swallow SR tabs must be swallowed whole; follow monitor K+; Cl− salt OK w/ alkalosis; w/ acidosis use acetate, bicarbonate, citrate, or gluconate salt; do not administer IV K+ undiluted.
PRAMOXINE (ANUSOL OINTMENT, PROCTOFOAM-NS, OTHERS)
USES: *Relief of pain & itching from hemorrhoids, anorectal surgery*; topical for burns & dermatosis.
ACTIONS: Topical anesthetic.
DOSE: Apply freely to anal area 3–5×/d.
W/P: [C, ?].
DISP: [OTC] All 1%; foam (ProctoFoam-NS), cream, oint, lotion, gel, pads, spray.
SE: Contact dermatitis, mucosal thinning w/ chronic use.
PRAMOXINE/HYDROCORTISONE (PROCTOFOAM-HC)
USES: *Relief of pain & itching from hemorrhoids.*
ACTIONS: Topical anesthetic, anti-inflammatory.
DOSE: Apply freely to anal area TID–QID.
W/P: [C, ?/−].
DISP: Cream: Pramoxine 1% acetate 1/2.5/2.35%, foam: Pramoxine 1% hydrocortisone 1%; lotion: Pramoxine 1% hydrocortisone 1/2.5%; ointment pramoxine 1% & hydrocortisone 1/2.5%.
SE: Contact dermatitis, mucosal thinning w/ chronic use
PRAZOSIN (MINIPRESS, GENERIC)
USES: *HTN *
ACTIONS: Peripherally acting α-adrenergic blocker.
DOSE:
Adults: 1 mg PO TID; can ↑ to 20 mg/d max. PRN.
Peds: 0.05–0.1 mg/kg/d in 3 ÷ doses; max. 0.5 mg/kg/d.
W/P: [C, ?] Use w/ phosphodiesterase-5 (PDE5) inhibitor (eg, sildenafil) can cause ↓ BP.
CI: Component allergy, concurrent use of PDE5 inhibitor.
DISP: Caps 1, 2, 5 mg; tabs ER 2.5, 5 mg.
SE: Dizziness, edema, palpitations, fatigue, GI upset.
NOTES: Can cause orthostatic ↓ BP, take the 1st dose hs; tolerance develops to this effect; tachyphylaxis may result.
PREDNISOLONE (FLO-PRED, OMNIPRED, PEDIAPRED, GENERIC)
See Steroids pages 968, 969
PREDNISONE (GENERIC)
See Steroids pages 968, 969
PREGABALIN (LYRICA, GENERIC)
USES: *DM peripheral neuropathy pain; postherpetic neuralgia; fibromyalgia; adjunct w/ adult partial onset seizures
ACTIONS: Nerve transmission modulator, antinociceptive, antiseizure effect; mechanism uncertain; related to gabapentin.
DOSE: Neuropathic pain: 50 mg PO TID, ↑ to 300 mg/d w/in 1 wk based on response, 300 mg/d max. Postherpetic neuralgia: 75–150 mg BID or 50–100 mg TID; start 75 mg BID or 50 mg TID; ↑ to 300 mg/d w/in 1 wk PRN; if pain persists after 2–4 wk, ↑ to 600 mg/d. Partial onset seizure: Start 150 mg/d (75 mg BID or 50 mg TID) may ↑ to max. 600 mg/d; ↓ w/ CrCl <60; w/ or w/o food.
W/P: [C, −] w/ Sig renal impairment (see PI), w/ elderly & severe CHF avoid abrupt D/C.
CI: Hypersensitivity.
DISP: Caps 25, 50, 75, 100, 150, 200, 225, 300 mg; soln 20 mg/mL.
SE: Dizziness, drowsiness, xerostomia, edema, blurred vision, Wt gain, difficulty concentrating; suicidal ideation.
NOTES: w/ D/C, taper over at least 1 wk.
PROBENECID (PROBALAN, GENERIC)
USES: *Prevent gout & hyperuricemia; extends levels of PCNs & cephalosporins.*
ACTIONS: Uricosuric, renal tubular blocker of weak organic anions.
DOSE:
Adults: Gout: 250 mg BID × 1 wk, then 500 mg PO BID; can ↑ by 500 mg/mo up to 2–3 g/d. Antibiotic effect: 1–2 g PO 30 min before dose.
Peds: >2 yr: 25 mg/kg, then 40 mg/kg/d PO QID.
W/P: [B, ?].
CI: Uric acid kidney stones, initiations during acute gout attack, coadministration of salicylates, age <2 yr, MDD, renal impairment.
DISP: Tabs 500 mg.
SE: Headache, GI upset, rash, pruritus, dizziness, blood dyscrasias.
PROPANTHELINE (PRO-BANTHINE, GENERIC)
USES: *Adjunctive therapy in the treatment of peptic ulcer *, symptomatic Treat small intestine hypermotility, spastic colon, ureteral spasm, bladder spasm, pylorospasm.
ACTIONS: Antimuscarinic.
DOSE:
Adults: 15 mg PO ac & 30 mg PO hs; ↓ in elderly.
Peds: 2–3 mg/kg/24 h PO ÷ 3–4×/d.
W/P: [C, ?].
CI: Glaucoma, severe ulcerative colitis, toxic megacolon, GI atony in elderly, myasthenia gravis, GI/GU obst.
DISP: 15 mg.
SE: Anticholinergic (eg, xerostomia, blurred vision).
PROPRANOLOL (INDERAL LA, INNOPRAN XL, GENERIC)
USES: *HTN, angina, MI, hyperthyroidism, essential tremor, hypertrophic subaortic stenosis, pheochromocytoma; prevents migraines & atrial arrhythmias*, thyrotoxicosis.
ACTIONS: β-Adrenergic receptor blocker, β1, β2; only β-blocker to block conversion of T4 to T3.
DOSE:
Adults: Angina: 80–320 mg/d PO ÷ 2–4×/d or 80–320 mg/d SR. Arrhythmia: 10–30 mg/dose PO q6–8h or 1 mg IV slowly, repeat q5min, 5 mg max. HTN: 40 mg PO BID or 60–80 mg/d SR, weekly to max. 640 mg/d. Hypertrophic subaortic stenosis: 20–40 mg PO 3–4×/d. MI: 180–240 mg PO ÷ 3–4×/d. Migraine prophylaxis: 80 mg/d ÷ 3–4×/d, ↑ weekly 160–240 mg/d ÷ 3–4 ×/d max.; wean if no response in 6 wk. Pheochromocytoma: 30–60 mg/d ÷ 3–4×/d. Thyrotoxicosis: 1–3 mg IV × 1; 10–40 mg PO q6h. Tremor: 40 mg PO BID, ↑ PRN 320 mg/d max. ECC 2010. SVT: 0.5–1 mg IV given over 1 min; repeat PRN up to 0.1 mg/kg.
Peds: Arrhythmia: 0.5–1.0 mg/kg/d ÷ 3–4×/d, ↑ PRN q3–7d to 8 mg/kg max.; 0.01–0.1 mg/kg IV over 10 min, 1 mg max. infants, 3 mg max. children. HTN: 0.5–1.0 mg/kg ÷ 3–4×/day, PRN q3–7d to 8 mg/kg/d max.; ↓ in renal impairment.
W/P: [C (1st tri, D if 2nd or 3rd tri), +].
CI: Uncompensated CHF, cardiogenic shock, HR, heart block, PE, severe resp disease.
DISP: Tabs 10, 20, 40, 80 mg; SR caps 60, 80, 120, 160 mg; oral soln 4, 8, mg/ mL; Inj 1 mg/mL.
SE: ↓ HR, ↓ BP, fatigue, GI upset, erectile dysfunction.
PROTAMINE (GENERIC)
WARNING: Severe ↓ BP, CV collapse, noncardiogenic pulm edema, pulm vasoconstriction, and pulm HTN can occur; risk factors: high dose/ overdose, repeat doses, prior protamine use, current or use of prior protamine-containing product (eg, NPH or protamine zinc insulin, some β-blockers), fish allergy, prior vasectomy, severe LV dysfunction, abnormal pulm testing; weigh risk/benefit in pts w/ 1 or more risk factors; resuscitation equipment must be available.
USES: *Reverse heparin effect.*
ACTIONS: Neutralize heparin by forming a stable complex.
DOSE: Based on degree of heparin reversal; give IV slowly; 1 mg reverses ∼100 U of heparin given in the preceding 30 min; 50 mg max.
W/P: [C, ?].
CI: Allergy.
DISP: Inj 10 mg/mL.
SE: Follow coagulation markers; anticoagulant effect if given w/o heparin; ↓ BP, ↓ HR, dyspnea, hemorrhage.
NOTES: Check aPTT ∼15 min after use to assess response.
PROTHROMBIN COMPLEX CONCENTRATE, HUMAN (KCENTRA)
WARNING: Risk vit K antag reversal w/ a thromboembolic event, must be weighed against the risk of NOT reversing vitamin K antag; this risk is higher in those who have had a prior thromboembolic event. Fatal and non-fatal arterial and venous thromboembolic events have occurred. Monitor. May not be effective in pts w/ thromboembolic events in the prior 3 mo.
USES: *Urgent reversal of acquired coagulation factor deficiencies caused by vit K antagonists; only for acute major bleeding.*
ACTIONS: Reverse vit K antag coagulopathy; replaces Factor II, VII, IX, X & Protein C & S.
DOSE: Based on INR and wgt: INR 2–4, 25 U/kg, 2,500 U max.; INR 4–6, 35 U/kg, 3,500 U max.; INR >6, 50 U/kg, 5,000 U max.; 100 mg/kg max.; give w/ vit K.
W/P: [C, ?] Hypersensitivity reaction; arterial/venous thrombosis; risk of viral Infxn including variant CJD.
CI: Anaphylaxis/reactions to: heparin, albumin or coag factors (Protein C & S, antithrombin III); known HIT DIC.
DISP: Single vial, to reconstitute, see package; separate IV for inf.
SE: Thromboembolic events (stroke, DVT/PE); DIC; ↓ BP, HA, N/V, HA, arthralgias.
NOTES: INR should be <1.3 w/in 30 min; risk of transmitting variant CJD, viral Dz (human blood product), and other Infxn (Hep A, B & C, HIV, etc.).
PSEUDOEPHEDRINE (MANY OTC MONO AND COMBINATION BRANDS)
USES: *Decongestant*, retrograde ejaculation.
ACTIONS: Stimulates α-adrenergic receptors w/ vasoconstriction.
DOSE:
Adults: IR: 60 mg PO q4–6h PRN; ER: 120 mg PO q12h, 240 mg/d max.; Retrograde ejaculation: Up to 60 mg, PO QID for 2–14 days.
Peds: 2–5 yr: 15 mg q4–6h, 60 mg/24 h max. 6–12 yr: 30 mg q4–6h, 120 mg/24 h max.; ↓ w/ renal insufficiency.
W/P: [C, +] Not rec for use in peds <6 yr.
CI: Poorly controlled HTN or CAD, w/ MAOIs w/in 14 days, urinary retention.
DISP: Immediate release tabs 30, 60 mg; ER caplets 60, 120 mg; ER tabs 120, 240 mg; liq 15, 30 mg/5 mL; syrup 15, 30 mg/5mL; multiple combo OTC products.
SE: HTN, insomnia, tachycardia, arrhythmias, nervousness, tremor.
NOTES: Found in many OTC cough/cold preparations; OTC restricted distribution by state (illicit ingredient in methamphetamine production).
PYRAZINAMIDE (GENERIC)
USES: *Active TB in combo w/ other agents.*
ACTIONS: Bacteriostatic; unknown mechanism.
DOSE:
Adults: Dose varies based on Tx option chosen daily 1 × 2 wk–3 × wk; dosing based on lean body Wt; ↓ dose in renal/hepatic impairment.
Peds: 20–40 mg/kg/d PO ÷ daily–BID; ↓ W/ renal/hepatic impairment.
W/P: [C, +/−].
CI: Severe hepatic damage, acute gout.
DISP: Tabs 500 mg.
SE: Hepatotox, malaise, GI upset, arthralgia, myalgia, gout, photosensitivity.
NOTES: Use in combo w/ other anti-TB drugs; consult http://www.cdc.gov/tb/ for latest TB recommendations; dosage regimen differs for “directly observed” Treat.
PYRIDOXINE [VITAMIN B6] (GENERIC)
USES: *Treat & prevention of vit B6 deficiency* supplement when on INH, idiopathic hyperoxaluria.
ACTIONS: Vit B6 supl.
DOSE:
Adults: Deficiency: 10–20 mg/d PO. Drug-induced neuritis: 100–200 mg/d; 25–100 mg/d prophylaxis.
Peds: 5–25 mg/d × 3 wk.
W/P: [A (C if doses exceed RDA), +].
CI: Component allergy tabs 25, 50, 100, 250, 500 mg, tab SR 500 mg; liquid 200 mg, 15 mg; Inj: 100 mg/mL; caps: 50, 250.