acetohydroxamic acid

Reversibly inhibits the bacterial enzyme, urease, which results in decreased hydrolysis of urea and subsequent production of ammonia in urine infected with urea-splitting bacteria.

Therapeutic effects:

Decreased urinary ammonia levels and decreased urine pH, which increases the efficacy of anti-infective therapy and cure rates.
Does not directly alter pH or have any direct antibacterial activity.

Pharmacokinetics ⬆ ⬇

Absorption: Well absorbed following oral administration.

Distribution: Distributed primarily to urine.

Metabolism/Excretion: 36–65% excreted unchanged in urine.

Half-Life: 5–10 hr (↑ in renal impairment).

Time/Action Profile ⬆ ⬇

(effect on urine)

ROUTE	ONSET	PEAK	DURATION
PO	4–8 hr	0.25–1 hr‡	6–8 hr

‡Plasma concentrations.

Contraind./Precautions ⬆ ⬇

Contraindicated in:

Urinary tract infection with non-urea-splitting organisms;
Urinary tract infections that can be controlled by culture-specific oral antibiotics;
Serum creatinine >2.5 mg/dL or CCr <20 mL/min;
OB: Pregnancy;
Lactation: Lactation.

Use Cautiously in:

Pre-existing thrombophlebitis or phlebothrombosis (↑ risk of adverse reactions);
Renal impairment (↓dose);
Hepatic impairment;
Rep: Women of reproductive potential;

Adv. Reactions/Side Effects ⬆ ⬇

CV: palpitations, superficial phlebitis of the lower extremities

Derm: alopecia, rash

GI: anorexia, nausea, vomiting

Hemat: anemia, hemolytic anemia

Neuro: anxiety, depression, headache, malaise, nervousness

Interactions ⬆ ⬇

Drug-drug:

May ↓ absorption and effectiveness of iron.
Iron may ↓ absorption and effectiveness.
Alcohol↑ risk of rash.

Route/Dosage ⬆ ⬇

PO (Adults ): 250 mg 3–4 times daily (total dose 10–15 mg/kg/day) (max dose = 1500 mg/day).
PO (Children ): 10 mg/kg/day in divided doses; further titration may be necessary.

Renal Impairment

PO (Adults ): Serum creatinine 1.8–2.5 mg/dL: do not exceed 1000 mg/day (given at 12 hr intervals; further adjustments may be necessary).

Availability ⬆ ⬇

Assessment ⬆ ⬇

Assess patient for signs/symptoms of urinary tract infection (fever, dysuria, polyuria, hematuria, flank pain, suprapubic pain or pressure) throughout therapy.

Lab Test Considerations:

Monitor CBC including reticulocyte count after 2 wk of treatment and every 3 mo during therapy. Reticulocytosis and hemolytic anemia may occur. If reticulocyte count >6%, ↓ dose.
- Monitor renal and hepatic function closely during therapy.

Implementation ⬆ ⬇

If a patient requires iron for a microcytic anemia, IM iron can be used during therapy.
PO: Administer on an empty stomach, 1 hr before or 2 hr after meals.

Patient/Family Teaching ⬆ ⬇

Explain the purpose and side effects of acetohydroxamic acid. Instruct patient to take exactly as directed on an empty stomach. Call healthcare professional if a dose is missed, as drug should be taken on a regular schedule. Do not share medication with others, even if they have similar symptoms; may be harmful. Advise patient to read Patient Information before starting and with each Rx refill in case of changes.
Inform patient that mild headache may occur during 1st 48 hr of treatment. Headaches usually respond to oral salicylates (aspirin) and usually disappear spontaneously.
Instruct patient to report signs/symptoms of hemolytic anemia (fatigue, weakness, trouble breathing, fast heartbeat, pale skin, yellowing of the skin and eyes, dark urine).
Advise patient that taking acetohydroxamic acid concurrently with alcohol may cause a nonpruritic macular skin rash to occur on upper extremities and face. Rash usually appears 30–45 min after ingestion of alcohol and may be associated with a sensation of warmth. It usually spontaneously disappears in 30–60 min.
Emphasize the importance of periodic lab tests to monitor for side effects.
Advise patient to notify health care professional of all Rx or OTC medications, vitamins, or herbal products being taken and to consult with health care professional before taking other medications.
Rep: May cause fetal harm. Advise women of reproductive potential to notify health care professional if pregnancy is planned or suspected or if breastfeeding. Advise women of reproductive potential to use a reliable form of contraception during therapy.

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Pronunciation ⬇

Classifications ⬆ ⬇

Indications ⬆ ⬇

Action ⬆ ⬇