Nursing 552
Pharmacology for Family Nurse Practitioners

• Sulfamethoxasole/trimethoprim (SMX/TMP)
• 5mls of the suspension per 10 kg weight per dose with BID dosing (suspension is 200mg/40mg per 5mls)

J.J. is allergic to penicillin (she gets hives) , therefore all members of the penicillin family including ampicillin, amoxicillin, and Augmentin are contraindicated. Since penicillins and cephalosporins have a 10% cross-reactivity rate, I would avoid cephalexin unless there was no other good choice. Ciprofloxacin is not approved for use in children under 18 years for urinary tract infections because of tendon alterations in juvenile lab animals so I would avoid that drug. Both SMX/TMP and nitrofurantoin can be used safely, however SMX/TMP is much less expensive and commonly used in children. SMX/TMP is effective against most common causes of UTI, the aerobic enteric pathogens excluding only pseudomonas. Children need to complete a 10-day course. Lehne, 3rd ed. PP 900-901. NP Drug handbook, 2nd ed. pp.: 1000-2, 1082-83, 59-62, 67-9, 203-4, 235-6, 774-5

Rx:

• Sulfamethoxasole/trimethoprim (200mg/40mg) per 5 ml suspension
• Take 15 mls ( 3 teaspoons) every twelve hours for ten days
• Dispense 300 mls
• No refills.

Rationale for Amount Rx'd
300 mls is the amount needed to complete this course of medication as furnished.

Drug Interactions
SMX/TMP affect the metabolism of anticoagulants, increasing the effect of the anticoagulants by displacing them from protein binding sites during hepatic metabolism, so warfarin levels should be checked during therapy. Drug levels of sulfonureas may also be elevated by a similar mechanism so hypoglycemia may occur, and sulfonurea doses may need to be adjusted downward. Other highly protein bound drugs such as cyclosporine, methotrexate, and phenytoin may be displaced, raising free drug levels and possibly toxicity of these drugs.

Side Effects
These may include allergic skin reactions: rash, urticaria, photosensitivity; nausea, vomiting, blood dyscrasias, hepatitis, Steven-Johnson syndrome, toxic epidermal necrolysis, as well as (rarely) confusion, depression, hallucinations, seizures, fever, ataxia, stomatitis, diarrhea, colitis, thrombocytopenia, megaloblastic anemia, granulocytopenia, aplastic anemia, hemolysis in persons with G6PD deficiency, kernicterus in newborns, and insterstitial nephritis.

Patient Instructions and Education
Take medication on an empty stomach with a full 8-ounce glass of water one hour before or two hours after meals. Don't skip doses. Do finish all the medicine. Wear sunscreen and protective clothing in case of photosensitivity. Small frequent meals and hard candy may decrease nausea if this occurs. Drink increased fluids throughout the day to help flush bacteria away and bring the medicine to the bladder. Report any unusual skin rash, bleeding, bruising or sore throat to your practitioner right away.