Lopurin
allopurinol
(al-oh-pure-i-nole) allopurinol,Aloprim
(trade name),Alloprin
(trade name),Lopurin
(trade name),Zyloprim
(trade name)Classification
Therapeutic: antigout agentsPharmacologic: xanthine oxidase inhibitors
Indications
Action
Therapeutic effects
Pharmacokinetics
Time/action profile (hypouricemic effect)
| ROUTE | ONSET | PEAK | DURATION |
|---|---|---|---|
| PO, IV | 1–2 days | 1–2 wk | 1–3 wk† |
Contraindications/Precautions
Adverse Reactions/Side Effects
Cardiovascular
- hypotension
- flushing
- hypertension
- bradycardia
- and heart failure (reported with IV administration)
Central nervous system
- drowsiness
Gastrointestinal
- diarrhea
- hepatitis
- nausea
- vomiting
Genitourinary
- renal failure
- hematuria
Dermatologic
- rash (discontinue drug at first sign of rash) (most frequent)
- urticaria
Hematologic
- bone marrow depression
Miscellaneous
- hypersensitivity reactions
Interactions
Drug-Drug interaction
Use with mercaptopurine and azathioprine ↑ bone marrow depressant properties—doses of these drugs should be ↓.Use with ampicillin or amoxicillin ↑ risk of rash.Use with oral hypoglycemic agents and warfarin ↑ effects of these drugs.Use with thiazide diuretics or ACE inhibitors ↑ risk of hypersensitivity reactions.Large doses of allopurinol may ↑ risk of theophylline toxicity.May ↑ cyclosporine levels.Route/Dosage
Management of GoutRenal Impairment
(Adults and Children) CCr 10–50 mL/min—↓ dose to 50% of recommended; CCr <10 mL/min—↓ dosage to 30% of recommended.Availability (generic available)
Nursing implications
Nursing assessment
- Monitor intake and output ratios. Decreased kidney function can cause drug accumulation and toxic effects. Ensure that patient maintains adequate fluid intake (minimum 2500–3000 mL/day) to minimize risk of kidney stone formation.
- Assess patient for rash or more severe hypersensitivity reactions. Discontinue allopurinol immediately if rash occurs. Therapy should be discontinued permanently if reaction is severe. Therapy may be reinstated after a mild reaction has subsided, at a lower dose (50 mg/day with very gradual titration). If skin rash recurs, discontinue permanently.
- Gout: Monitor for joint pain and swelling. Addition of colchicine or NSAIDs may be necessary for acute attacks. Prophylactic doses of colchicine or an NSAID should be administered concurrently during the first 3–6 mo of therapy because of an increased frequency of acute attacks of gouty arthritis during early therapy.
- Lab Test Considerations: Serum and urine uric acid levels usually begin to ↓ 2–3 days after initiation of oral therapy.
- Monitor blood glucose in patients receiving oral hypoglycemic agents. May cause hypoglycemia.
- Monitor hematologic, renal, and liver function tests before and periodically during therapy, especially during the first few mo. May cause ↑ serum alkaline phosphatase, bilirubin, AST, and ALT levels. ↓ CBC and platelets may indicate bone marrow depression. ↑ BUN, serum creatinine, and CCr may indicate nephrotoxicity. These are usually reversed with discontinuation of therapy.
Potential Nursing Diagnoses
Acute pain (Indications)Implementation
- Oral: May be administered after milk or meals to minimize gastric irritation; give with plenty of fluid. May be crushed and given with fluid or mixed with food for patients who have difficulty swallowing.
Intravenous Administration
- pH: 10.8–11.8.
- Intermittent Infusion: Reconstitute each 500 mg vial with 25 mL of sterile water for injection. Solution should be clear and almost colorless with only slight opalescence. Diluent: Dilute to desired concentration with 0.9% NaCl or D5W. Administer within 10 hr of reconstitution; do not refrigerate. Do not administer solutions that are discolored or contain particulate matter.Concentration: Not >6 mg/mL.
- Rate: Infusion should be initiated 24–48 hr before start of chemotherapy known to cause tumor cell lysis. Rate of infusion depends on volume of infusate (100–300 mg doses may be infused over 30 minutes). May be administered as a single infusion or equally divided infusions at 6-, 8-, or 12-hr intervals.
- Y-Site Compatibility: acyclovir, aminophylline, amphotericin B lipid complex, anidulafungin, argatroban, aztreonam, bivalirudin, bleomycin, bumetanide, buprenorphine, butorphanol, calcium gluconate, carboplatin, caspofungin, cefazolin, cefotetan, ceftazidime, ceftriaxone, cefuroxime, cisplatin, cyclophosphamide, dactinomycin, dexamethasone sodium phosphate, dexmedetomidine, docetaxel, doxorubicin liposome, enalaprilat, etoposide, famotidine, fenoldopam, filgrastim, fluconazole, fludarabine, fluorouracil, furosemide, ganciclovir, gemcitabine, granisetron, heparin, hetastarch, hydrocortisone, hydromorphone, ifosfamide, leucovorin calcium, linezolid, lorazepam, mannitol, mesna, methotrexate, metronidazole, milrinone, mitoxandrone, morphine, nesiritide, octreotide, oxytocin, paclitaxel, pamidronate, pantoprazole, pemetrexed, piperacillin/tazobactam, potassium chloride, ranitidine, sodium acetate, teniposide, thiotepa, ticarcillin/clavulanate, tigecycline, tirofiban, trimethoprim/sulfamethoxazole, vancomycin, vasopressin, vinblastine, vincristine, voriconazole, zidovudine, zoledronic acid
- Y-Site Incompatibility: alemtuzumab, amikacin, amphotericin B colloidal, carmustine, cefotaxime, chlorpromazine, clindamycin, cytarabine, dacarbazine, daptomycin, daunorubicin, dexrazoxane, diltiazem, diphenhydramine, doxorubicin, doxycycline, droperidol, epirubicin, ertapenem, etoposide phosphate, floxuridine, foscarnet, gentamicin, haloperidol, hydroxyzine, idarubicin, imipenem/cilastatin, irinotecan, mechlorethamine, meperidine, methylprednisolone sodium succinate, metoprolol, moxifloxacin, mycophenolate, nalbuphine, ondansetron, palonosetron, pancuronium, potassium acetate, prochlorperazine, promethazine, sodium bicarbonate, streptozocin, tacrolimus, tobramycin, vecuronium, vinorelbine
Patient/Family Teaching
- Instruct patient to take allopurinol as directed. Take missed doses as soon as remembered. If dosing schedule is once daily, do not take if remembered the next day. If dosing schedule is more than once a day, take up to 300 mg for the next dose.
- Instruct patient to continue taking allopurinol along with an NSAID or colchicine during an acute attack of gout. Allopurinol helps prevent, but does not relieve, acute gout attacks.
- Alkaline diet may be ordered. Urinary acidification with large doses of vitamin C or other acids may increase kidney stone formation (see ). Advise patient of need for increased fluid intake.
- May occasionally cause drowsiness. Caution patient to avoid driving or other activities requiring alertness until response to drug is known.
- Instruct patient to report skin rash, blood in urine, or influenza symptoms (chills, fever, muscle aches and pains, nausea, or vomiting) to health care professional immediately; skin rash may indicate hypersensitivity.
- Advise patient that large amounts of alcohol increase uric acid concentrations and may decrease the effectiveness of allopurinol.
- Emphasize the importance of follow-up exams to monitor effectiveness and side effects.
Evaluation/Desired Outcomes
- Decreased serum and urinary uric acid levels. May take 2–6 wk to observe clinical improvement in patients treated for gout.