acetohydroxamic acid

Therapeutic Classification: anti-infectives (adjunct)

Pharmacologic Classification: urease inhibitors

Indications ⬆ ⬇

REMS

Adjunct therapy in chronic urea-splitting urinary tract infection.

Action ⬆ ⬇

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 throughout body water.

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

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

Time/Action Profile ⬆ ⬇

(effect on urine)

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

‡Blood levels.

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: Causes birth defects; women of childbearing potential must use adequate contraception;
Lactation: Safety not established.

Use Cautiously in:

Renal impairment (increased risk of adverse reactions; dosage reduction recommended);
Hepatic impairment;
Pre-existing thrombophlebitis or phlebothrombosis (increased risk of adverse reactions).

Adv. Reactions/Side Effects ⬆ ⬇

CV: palpitations, superficial phlebitis of the lower extremities

Derm: alopecia, rash (in association with alcohol)

GI: anorexia,, nausea,, vomiting

Hemat: anemia, hemolytic anemia

Neuro: anxiety, depression, headache, malaise, nervousness, tremulousness

Interactions ⬆ ⬇

Drug-drug:

Decreases absorption of iron.
Iron decreases the absorption of acetohydroxamic acid.
Concurrent ingestion of alcohol increases the incidence of rash.

Route/Dosage ⬆ ⬇

PO (Adults ): 250 mg 3–4 times daily (total dose 10–15 mg/kg/day)(maximum daily dose = 1500 mg).
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 and symptoms of urinary tract infection (frequency, urgency, fever, pus in urine) 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 is >6%, reduce dose.
- Monitor renal and hepatic function closely during therapy.

Implementation ⬆ ⬇

If a patient requires iron for a microcytic anemia, intramuscular iron can be used during the course of treatment with acetohydroxamic acid.
PO: Administer on an empty stomach, 1 hr before or 2 hr after meals.

Patient/Family Teaching ⬆ ⬇

Instruct patient to take medication exactly as directed.
Inform patient that mild headache may occur during first 48 hr of treatment. Headaches usually respond to oral salicylates (aspirin) and usually disappear spontaneously.
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.
Caution patients of childbearing potential to use a reliable form of contraception while taking acetohydroxamic acid.

Evaluation/Desired Outcomes ⬆ ⬇

Decreased urinary ammonia levels and decreased urine pH which increases the efficacy of anti-infective therapy and cure rates in urinary tract infections.

US Brand Names ⬆ ⬇

Code ⬆

NDC Code

0178- Mission Pharmacal Company
- 0178-0500- Lithostat
  - 0178-0500-01- 100 TABLET in 1 BOTTLE (0178-0500-01)

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Pronunciation ⬇

Classifications ⬆ ⬇