Monitor for toxicity and consider dose reduction of saquinavir ( 7.1 ) • May interfere with drugs for which gastric pH affects bioavailability (e.g., ketoconazole, iron salts, erlotinib, ampicillin esters, and digoxin). Like with other drugs that decrease the intragastric acidity, the absorption of drugs such as ketoconazole, ampicillin esters, iron salts and erlotinib can decrease, while the absorption of drugs such as digoxin can increase during treatment with omeprazole.
Source: FDA drug label - omeprazole
An increase in the frequency of skin rash has been reported among patients receiving ampicillin or amoxicillin concurrently with allopurinol compared to patients who are not receiving both drugs.
Source: FDA drug label - allopurinol
7.6 Effects on Laboratory Tests High urine concentrations of ampicillin may result in false-positive reactions when testing for the presence of glucose in urine using CLINITEST ® , Benedict’s Solution, or Fehling’s Solution. Following administration of ampicillin or amoxicillin to pregnant women, a transient decrease in plasma concentration of total conjugated estriol, estriol-glucuronide, conjugated estrone, and estradiol has been noted.
Source: FDA drug label - amoxicillin
Drug Interactions The concurrent administration of allopurinol and ampicillin increases substantially the incidence of skin rashes in patients receiving both drugs as compared to patients receiving ampicillin alone. It is not known whether this potentiation of ampicillin rashes is due to allopurinol or the hyperuricemia present in these patients.
Source: FDA drug label - ampicillin sodium
Drug Interactions Probenecid decreases the renal tubular secretion of ampicillin and sulbactam. Concurrent use of probenecid with ampicillin and sulbactam for injection may result in increased and prolonged blood levels of ampicillin and sulbactam. The concurrent administration of allopurinol and ampicillin increases substantially the incidence of rashes in patients receiving both drugs as compared to patients receiving ampicillin alone.
Source: FDA drug label - ampicillin sodium and sulbactam sodium
Ampicillin: In a study of healthy volunteers, chloroquine significantly reduced the bioavailability of ampicillin. An interval of at least two hours between intake of ampicillin and chloroquine should be observed.
Source: FDA drug label - chloroquine phosphate
7.12 Ampicillin In a study of healthy volunteers, chloroquine significantly reduced the bioavailability of ampicillin. Interaction of ampicillin with hydroxychloroquine cannot be ruled out.
Source: FDA drug label - hydroxychloroquine sulfate
Examples of relevant classes of compounds where antacids have been demonstrated to reduce bioavailability include antibiotics (such as quinolones, ampicillin, and tetracyclines), thyroid hormones, ACE inhibitors, statin lipid regulators, and anti-malarials.
Source: FDA drug label - lanthanum carbonate
A similar association though less marked, has been suggested with barbiturates, phenylbutazone, phenytoin sodium, and possibly with griseofulvin, ampicillin and tetracyclines.
Source: FDA drug label - norethindrone and ethinyl estradiol
7.5 Other Concomitant Medications Raloxifene hydrochloride can be concomitantly administered with ampicillin, amoxicillin, antacids, corticosteroids, and digoxin [see Clinical Pharmacology (12.3) ] .
Source: FDA drug label - raloxifene hydrochloride
Drugs that have been documented not to interact with theophylline or drugs that produce no clinically significant interaction with theophylline.* albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without methylprednisolone sulbactam metronidazole atenolol metoprolol azithromycin nadolol caffeine, dietary ingestion nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin * Refer to PRECAUTIONS, Drug Interactions for information regarding table.
Source: FDA drug label - theophylline
albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without sulbactam methylprednisolone atenolol metronidazole azithromycin metoprolol caffeine, dietary ingestion nadolol cefaclor nifedipine co-trimoxazole (trimethoprim and sulfamethoxazole) nizatidine diltiazem norfloxacin dirithromycin ofloxacin enflurane omeprazole famotidine prednisone, prednisolone felodipine ranitidine finasteride rifabutin hydrocortisone roxithromycin isoflurane Sorbitol (purgative doses do not inhibit theophylline absorption) isoniazid sucralfate isradipine terbutaline, systemic influenza vaccine terfenadine ketoconazole tetracycline lomefloxacin tocainide
Source: FDA drug label - theophylline anhydrous
High urine concentrations of ampicillin or amoxicillin may cause false-positive results when using glucose tests based on the Benedict's copper reduction reaction that determines the amount of reducing substances like glucose in the urine. High urine concentrations of ampicillin or amoxicillin may cause false-positive results when using glucose tests based on the Benedict's copper reduction reaction that determines the amount of reducing substances like glucose in the urine.
Source: FDA drug label - vonoprazan fumarate and amoxicillin