Clinician's Pocket Drug Reference 2008

208 TrihexyphenidylTrihexyphenidyl (Artane) Uses: *Parkinson Dz* Action: Blocks excessacetylcholine at cerebral synapses Dose: 2–5 mg PO daily–qid Caution: [C, +]Contra: NAG, GI obst, MyG, bladder obstructions Disp: Tabs 2, 5 mg; SR caps 5mg; elixir 2 mg/5 mL SE: Dry skin, constipation, xerostomia, photosens, tachycardia,arrhythmiasTrimethobenzamide (Tigan) Uses: *N/V* Action: ↓ medullarychemoreceptor trigger zone Dose: Adults. 250 mg PO or 200 mg PR or IM tid–qidPRN. Peds. 20 mg/kg/24 h PO or 15 mg/kg/24 h PR or IM in 3–4 ÷ doses Caution:[C, ?] Contra: Benzocaine sensitivity Disp: Caps 100, 250 mg; supp 100,200, 300 mg; inj 100 mg/mL SE: Drowsiness, ↓ BP, dizziness; hepatic impair,blood dyscrasias, Szs, parkinsonian-like synd Notes: In the presence of viral Infxns,may mask emesis or mimic CNS effects of Reye’s syndTrimethoprim (Trimpex, Proloprim) Uses: *UTI due to susceptiblegram (+) & gram (–) organisms;* suppression of UTI Action: ↓ dihydrofolate reductase.Spectrum: Many gram (+) & (–) except Bacteroides, Branhamella, Brucella,Chlamydia, Clostridium, Mycobacterium, Mycoplasma, Nocardia, Neisseria,Pseudomonas, & Treponema Dose: Adults. 100 mg/d PO bid or 200 mg/d PO.Peds. 4 mg/kg/d in 2 ÷ doses; ↓ w/ renal failure Caution: [C, +] Contra: Megaloblasticanemia due to folate deficiency Disp: Tabs 100, 200 mg; PO soln 50 mg/5mL SE: Rash, pruritus, megaloblastic anemia, hepatic impair, blood dyscrasiasNotes: Take w/ plenty of H 2 OTrimethoprim (TMP)–Sulfamethoxazole (SMX) [Co-Trimoxazole](Bactrim, Septra) Uses: *UTI Rx & prophylaxis, otitis media, sinusitis,bronchitis* Action: SMX ↓ synth of dihydrofolic acid;, TMP ↓ dihydrofolatereductase to impair protein synth. Spectrum: Includes Shigella, P. jiroveci (formerlycarinii), & Nocardia Infxns, Mycoplasma, Enterobacter sp, Staph, Strep, & moreDose: Adults. 1 DS tab PO bid or 5–20 mg/kg/24 h (based on TMP) IV in 3–4 ÷doses. P. jiroveci: 15–20 mg/kg/d IV or PO (TMP) in 4 ÷ doses. Nocardia: 10–15mg/kg/d IV or PO (TMP) in 4 ÷ doses. UTI prophylaxis: 1 PO daily. Peds. 8–10mg/kg/24 h (TMP) PO ÷ into 2 doses or 3–4 doses IV; do not use in newborns; ↓ inrenal failure; maintain hydration Caution: [B (D if near term), +] Contra: Sulfonamidesensitivity, porphyria, megaloblastic anemia w/ folate deficiency, significanthepatic impair Disp: Regular tabs 80 mg TMP/400 mg SMX; DS tabs 160 mgTMP/800 mg SMX; PO susp 40 mg TMP/200 mg SMX/5 mL; inj 80 mg TMP/ 400mg SMX/5 mL SE: Allergic skin Rxns, photosens, GI upset, Stevens–Johnson synd,blood dyscrasias, hepatitis Notes: Synergistic combo, interacts w/ warfarinTrimetrexate (Neutrexin) WARNING: Must be used w/ leucovorin toavoid tox Uses: *Moderate–severe PCP* Action: ↓ dihydrofolate reductaseDose: 45 mg/m 2 IV q24h for 21 d; administer w/ leucovorin 20 mg/m 2 IV q6h for24 d; ↓ in hepatic impair Caution: [D, ?/–] Contra: MTX sensitivity Disp: Inj 25,200 mg/25 mg/vial SE: Sz, fever, rash, GI upset, anemias, ↑ LFTs, peripheral neuropathy,renal impair Notes: Use cytotoxic cautions; inf over 60 min