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Hypersensitivity to Metrodal or other nitroimidazoles (although cautious desensitization has been applied)
Pregnancy, 1st trimester in patients with trichomoniasis
Use of disulfiram within past 2 weeks; use of alcohol during therapy or within 3 days of discontinuing therapy
Which drugs or supplements interact with this medication?
- Alcohol should be avoided because Metrodal and alcohol together can cause severe nausea, vomiting, cramps, flushing, and headache.
- Metrodal can increase the blood thinning effects of warfarin (Coumadin, Jantoven) and increase the risk of bleeding probably by reducing the breakdown of warfarin.
- Cimetidine (Tagamet) increases blood levels of Metrodal while cholestyramine (Questran, Questran Light) reduces blood levels of Metrodal by reducing its absorption.
- Metrodal should not be combined with amprenavir (Agenerase) for treating human immunodeficiency disease (infection with HIV) because amprenavir contains propylene glycol.
- Metrodal blocks the breakdown of propylene glycol in the liver leading to accumulation of propylene glycol in blood. Accumulation of propylene glycol could cause seizures, increased heart rate, and lead to kidney failure.
- Metrodal increases the blood levels of carbamazepine (Tegretol, Tegretol XR, Equetro, Carbatrol), lithium (Eskalith, Lithobid) and cyclosporine though unknown mechanisms. Serious reactions may occur if these drugs are taken with Metrodal.
The following reactions have been reported during treatment with Metrodal:
What other information should I know?
Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your response to Metrodal.
Before having any laboratory test, tell your doctor and the laboratory personnel that you are taking Metrodal.
Do not let anyone else take your medication. Your prescription is probably not refillable. If you still have symptoms of infection after you finish the Metrodal, call your doctor.
It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.
Carcinogenesis, Mutagenesis, Impairment Of Fertility
Tumors affecting the liver, lungs, mammary, and lymphatic tissues have been detected in several studies of Metrodal in rats and mice, but not hamsters.
Pulmonary tumors have been observed in all six reported studies in the mouse, including one study in which the animals were dosed on an intermittent schedule (administration during every fourth week only). Malignant liver tumors were increased in male mice treated at approximately 1500 mg/m² (similar to the maximum recommended daily dose, based on body surface area comparisons). Malignant lymphomas and pulmonary neoplasms were also increased with lifetime feeding of the drug to mice. Mammary and hepatic tumors were increased among female rats administered oral Metrodal compared to concurrent controls. Two lifetime tumorigenicity studies in hamsters have been performed and reported to be negative.
Metrodal has shown mutagenic activity in in vitro assay systems including the Ames test. Studies in mammals in vivo have failed to demonstrate a potential for genetic damage.
Metrodal failed to produce any adverse effects on fertility or testicular function in male rats at doses up at 400 mg/kg/day (similar to the maximum recommended clinical dose, based on body surface area comparisons) for 28 days. However, rats treated at the same dose for 6 weeks or longer were infertile and showed severe degeneration of the seminiferous epithelium in the testes as well as marked decreases in testicular spermatid counts and epididymal sperm counts. Fertility was restored in most rats after an eight week, drug-free recovery period.
Serious Side Effects of Metrodal
Tell your doctor immediately if you experience any of the following serious side effects:
- Numbness or tingling in the hands or feet
- White patches or sores in the mouth or on the lips
- Painful urination
- Vision problems or pain behind the eyes
- Fever or chills
- Trouble concentrating
- Mood or behavior changes
- Slurred speech
- Stiff neck
- Muscle twitching
- Joint pain
- Signs of an allergic reaction, which may include rash, hives, difficulty breathing, or swelling of the face, lips, tongue, or throat
What are the side effects of Metrodal?
Flagyl is a useful antibiotic and is generally well tolerated with appropriate use.
The most common and minor side effects include:
Side effects that are uncomfortable, but may become serious include:
- Brain disease
- Mouth sores
- Pain with urination
- Prickling or tingling sensations that may become permanent
- Pelvic pain or pressure
- Decrease of libido
Serious side effects of Flagyl are rare and the drug should be stopped if these symptoms appear:
What other drugs will affect Metrodal?
Sometimes it is not safe to use certain medications at the same time. Some drugs can affect your blood levels of other drugs you take, which may increase side effects or make the medications less effective.
Tell your doctor about all your current medicines and any you start or stop using, especially:
a blood thinner - warfarin, Coumadin, Jantoven.
phenytoin or phenobarbital
This list is not complete. Other drugs may interact with Metrodal, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.
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To reduce the development of drugresistant bacteria and maintain the effectiveness of FLAGYL® and other antibacterial drugs, FLAGYL® should be used only to treat or prevent infections that are proven or strongly suspected to be caused by bacteria.
Metrodal has been shown to be carcinogenic in mice and rats (see PRECAUTIONS). Unnecessary use of the drug should be avoided. Its use should be reserved for the conditions described in the INDICATIONS AND USAGE section below.