Methyldopa: Difference between revisions
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{{DrugProjectFormSinglePage | {{DrugProjectFormSinglePage | ||
|genericName= | |authorTag={{Alonso}} | ||
|aOrAn= | |genericName=Methyldopa | ||
|drugClass= | |aOrAn=an | ||
|indication= | |drugClass=[[alpha-adrenergic blocker]] | ||
|indicationType=treatment | |||
|indication=[[hypertension]] | |||
|hasBlackBoxWarning=Yes | |hasBlackBoxWarning=Yes | ||
|adverseReactions=a list of adverse reactions, separated by commas. | |adverseReactions=a list of adverse reactions, separated by commas. | ||
| Line 110: | Line 112: | ||
:* (Dosage) | :* (Dosage) | ||
|contraindications=* | |contraindications=* Patients with active hepatic disease, such as [[acute hepatitis]] and active [[cirrhosis]]. | ||
* | * Patients with [[liver]] disorders previously associated with methyldopa therapy. | ||
* | * Patients with [[hypersensitivity]] to any component of this product. | ||
* | * Patients on therapy with [[monoamine oxidase inhibitors]] ([[MAO]]). | ||
( | |warnings='''It is important to recognize that a positive [[Coombs test]], [[hemolytic anemia]], and [[liver]] disorders may occur with methyldopa therapy. The rare occurrences of [[hemolytic anemia]] or [[liver]] disorders could lead to potentially fatal complications unless properly recognized and managed. Read this section carefully to understand these reactions.''' | ||
With prolonged methyldopa therapy, 10 to 20 percent of patients develop a positive direct [[Coombs test]] which usually occurs between 6 and 12 months of methyldopa therapy. Lowest incidence is at daily dosage of 1 g or less. This on rare occasions may be associated with [[hemolytic anemia]], which could lead to potentially fatal complications. One cannot predict which patients with a positive direct Coombs test may develop [[hemolytic anemia]]. | |||
Prior existence or development of a positive direct Coombs test is not in itself a contraindication to use of methyldopa. If a positive Coombs test develops during methyldopa therapy, the physician should determine whether [[hemolytic anemia]] exists and whether the positive [[Coombs test]] may be a problem. For example, in addition to a positive direct Coombs test there is less often a positive indirect [[Coombs test]] which may interfere with cross matching of blood. | |||
Before treatment is started, it is desirable to do a blood count ([[hematocrit]], [[hemoglobin]], or red cell count) for a baseline or to establish whether there is [[anemia]]. Periodic blood counts should be done during therapy to detect [[hemolytic anemia]]. It may be useful to do a direct [[Coombs test]] before therapy and at 6 and 12 months after the start of therapy. | |||
If [[Coombs test|Coombs-positive]] [[hemolytic anemia]] occurs, the cause may be methyldopa and the drug should be discontinued. Usually the [[anemia]] remits promptly. If not, [[corticosteroids]] may be given and other causes of anemia should be considered. If the [[hemolytic anemia]] is related to methyldopa, the drug should not be reinstituted. | |||
When methyldopa causes [[Coombs test|Coombs positivity]] alone or with [[hemolytic anemia]], the red cell is usually coated with gamma globulin of the lgG (gamma G) class only. The positive [[Coombs test]] may not revert to normal until weeks to months after methyldopa is stopped. | |||
Should the need for [[transfusion]] arise in a patient receiving methyldopa, both a direct and an indirect Coombs test should be performed. In the absence of hemolytic anemia, usually only the direct Coombs test will be positive. A positive direct Coombs test alone will not interfere with typing or cross matching. If the indirect Coombs test is also positive, problems may arise in the major cross match and the assistance of a hematologist or transfusion expert will be needed. | |||
Occasionally, fever has occurred within the first three weeks of methyldopa therapy, associated in some cases with eosinophilia or abnormalities in one or more liver function tests, such as serum [[alkaline phosphatase]], serum [[transaminases]] ([[SGOT]], [[SGPT]]), [[bilirubin]], and [[prothrombin time]]. [[Jaundice]], with or without fever, may occur with onset usually within the first two to three months of therapy. In some patients the findings are consistent with those of [[cholestasis]]. In others the findings are consistent with [[hepatitis]] and hepatocellular injury. | |||
Rarely, fatal hepatic necrosis has been reported after use of methyldopa. These hepatic changes may represent [[hypersensitivity reactions]]. Periodic determinations of hepatic function should be done particularly during the first 6 to 12 weeks of therapy or whenever an unexplained fever occurs. If [[fever]], abnormalities in [[liver function tests]], or [[jaundice]] appear, stop therapy with methyldopa. If caused by methyldopa, the temperature and abnormalities in liver function characteristically have reverted to normal when the drug was discontinued. Methyldopa should not be reinstituted in such patients. | |||
Rarely, a reversible reduction of the white blood cell count with a primary effect on the [[granulocytes]] has been seen. The granulocyte count returned promptly to normal on discontinuance of the drug. Rare cases of [[granulocytopenia]] have been reported. In each instance, upon stopping the drug, the white cell count returned to normal. Reversible [[thrombocytopenia]] has occurred rarely. | |||
|clinicalTrials=======Central Nervous System====== | |clinicalTrials=======Central Nervous System====== | ||
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|othersTitle=Others | |othersTitle=Others | ||
|useInOthers=(Description) | |useInOthers=(Description) | ||
|administration=(Oral/Intravenous/etc) | |administration=(Oral/Intravenous/etc) | ||
|monitoring======Condition 1===== | |monitoring======Condition 1===== | ||
| Line 440: | Line 456: | ||
|howSupplied=(Description) | |howSupplied=(Description) | ||
|fdaPatientInfo=(Patient Counseling Information) | |fdaPatientInfo=(Patient Counseling Information) | ||
| | |alcohol=Alcohol-Methyldopa interaction has not been established. Talk to your doctor about the effects of taking alcohol with this medication. | ||
|lookAlike=* (Paired Confused Name 1a) — (Paired Confused Name 1b) | |lookAlike=* (Paired Confused Name 1a) — (Paired Confused Name 1b) | ||
* (Paired Confused Name 2a) — (Paired Confused Name 2b) | * (Paired Confused Name 2a) — (Paired Confused Name 2b) | ||
* (Paired Confused Name 3a) — (Paired Confused Name 3b) | * (Paired Confused Name 3a) — (Paired Confused Name 3b) | ||
|nlmPatientInfo=(Link to patient information page) | |||
|drugShortage=Drug Shortage | |drugShortage=Drug Shortage | ||
}} | }} | ||
Revision as of 19:03, 15 July 2014
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Alonso Alvarado, M.D. [2]
Disclaimer
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Black Box Warning
|
Warning Title
See full prescribing information for complete Boxed Warning.
Condition Name: (Content)
|
Overview
Methyldopa is an alpha-adrenergic blocker that is FDA approved for the treatment of hypertension. There is a Black Box Warning for this drug as shown here. Common adverse reactions include a list of adverse reactions, separated by commas..
Adult Indications and Dosage
FDA-Labeled Indications and Dosage (Adult)
Condition 1
- Dosing Information
- (Dosage)
Condition 2
- Dosing Information
- (Dosage)
Off-Label Use and Dosage (Adult)
Guideline-Supported Use
Condition 1
- Developed by: (Organisation)
- Class of Recommendation: (Class) (Link)
- Strength of Evidence: (Category A/B/C) (Link)
- Dosing Information/Recommendation
- (Dosage)
Condition 2
- Developed by: (Organisation)
- Class of Recommendation: (Class) (Link)
- Strength of Evidence: (Category A/B/C) (Link)
- Dosing Information/Recommendation
- (Dosage)
Non–Guideline-Supported Use
Condition 1
- Dosing Information
- (Dosage)
Condition 2
- Dosing Information
- (Dosage)
Condition 3
- Dosing Information
- (Dosage)
Pediatric Indications and Dosage
FDA-Labeled Indications and Dosage (Pediatric)
Condition 1
- Dosing Information
- (Dosage)
Condition 2
- Dosing Information
- (Dosage)
Off-Label Use and Dosage (Pediatric)
Guideline-Supported Use
Condition 1
- Developed by: (Organisation)
- Class of Recommendation: (Class) (Link)
- Strength of Evidence: (Category A/B/C) (Link)
- Dosing Information/Recommendation
- (Dosage)
Condition 2
- Developed by: (Organisation)
- Class of Recommendation: (Class) (Link)
- Strength of Evidence: (Category A/B/C) (Link)
- Dosing Information/Recommendation
- (Dosage)
Non–Guideline-Supported Use
Condition 1
- Dosing Information
- (Dosage)
Condition 2
- Dosing Information
- (Dosage)
Condition 3
- Dosing Information
- (Dosage)
Contraindications
- Patients with active hepatic disease, such as acute hepatitis and active cirrhosis.
- Patients with liver disorders previously associated with methyldopa therapy.
- Patients with hypersensitivity to any component of this product.
- Patients on therapy with monoamine oxidase inhibitors (MAO).
Warnings
|
Warning Title
See full prescribing information for complete Boxed Warning.
Condition Name: (Content)
|
It is important to recognize that a positive Coombs test, hemolytic anemia, and liver disorders may occur with methyldopa therapy. The rare occurrences of hemolytic anemia or liver disorders could lead to potentially fatal complications unless properly recognized and managed. Read this section carefully to understand these reactions.
With prolonged methyldopa therapy, 10 to 20 percent of patients develop a positive direct Coombs test which usually occurs between 6 and 12 months of methyldopa therapy. Lowest incidence is at daily dosage of 1 g or less. This on rare occasions may be associated with hemolytic anemia, which could lead to potentially fatal complications. One cannot predict which patients with a positive direct Coombs test may develop hemolytic anemia.
Prior existence or development of a positive direct Coombs test is not in itself a contraindication to use of methyldopa. If a positive Coombs test develops during methyldopa therapy, the physician should determine whether hemolytic anemia exists and whether the positive Coombs test may be a problem. For example, in addition to a positive direct Coombs test there is less often a positive indirect Coombs test which may interfere with cross matching of blood.
Before treatment is started, it is desirable to do a blood count (hematocrit, hemoglobin, or red cell count) for a baseline or to establish whether there is anemia. Periodic blood counts should be done during therapy to detect hemolytic anemia. It may be useful to do a direct Coombs test before therapy and at 6 and 12 months after the start of therapy.
If Coombs-positive hemolytic anemia occurs, the cause may be methyldopa and the drug should be discontinued. Usually the anemia remits promptly. If not, corticosteroids may be given and other causes of anemia should be considered. If the hemolytic anemia is related to methyldopa, the drug should not be reinstituted.
When methyldopa causes Coombs positivity alone or with hemolytic anemia, the red cell is usually coated with gamma globulin of the lgG (gamma G) class only. The positive Coombs test may not revert to normal until weeks to months after methyldopa is stopped.
Should the need for transfusion arise in a patient receiving methyldopa, both a direct and an indirect Coombs test should be performed. In the absence of hemolytic anemia, usually only the direct Coombs test will be positive. A positive direct Coombs test alone will not interfere with typing or cross matching. If the indirect Coombs test is also positive, problems may arise in the major cross match and the assistance of a hematologist or transfusion expert will be needed.
Occasionally, fever has occurred within the first three weeks of methyldopa therapy, associated in some cases with eosinophilia or abnormalities in one or more liver function tests, such as serum alkaline phosphatase, serum transaminases (SGOT, SGPT), bilirubin, and prothrombin time. Jaundice, with or without fever, may occur with onset usually within the first two to three months of therapy. In some patients the findings are consistent with those of cholestasis. In others the findings are consistent with hepatitis and hepatocellular injury.
Rarely, fatal hepatic necrosis has been reported after use of methyldopa. These hepatic changes may represent hypersensitivity reactions. Periodic determinations of hepatic function should be done particularly during the first 6 to 12 weeks of therapy or whenever an unexplained fever occurs. If fever, abnormalities in liver function tests, or jaundice appear, stop therapy with methyldopa. If caused by methyldopa, the temperature and abnormalities in liver function characteristically have reverted to normal when the drug was discontinued. Methyldopa should not be reinstituted in such patients.
Rarely, a reversible reduction of the white blood cell count with a primary effect on the granulocytes has been seen. The granulocyte count returned promptly to normal on discontinuance of the drug. Rare cases of granulocytopenia have been reported. In each instance, upon stopping the drug, the white cell count returned to normal. Reversible thrombocytopenia has occurred rarely.
Adverse Reactions
Clinical Trials Experience
Central Nervous System
- (list/description of adverse reactions)
Cardiovascular
- (list/description of adverse reactions)
Respiratory
- (list/description of adverse reactions)
Gastrointestinal
- (list/description of adverse reactions)
Hypersensitive Reactions
- (list/description of adverse reactions)
Miscellaneous
- (list/description of adverse reactions)
Condition 2
Central Nervous System
- (list/description of adverse reactions)
Cardiovascular
- (list/description of adverse reactions)
Respiratory
- (list/description of adverse reactions)
Gastrointestinal
- (list/description of adverse reactions)
Hypersensitive Reactions
- (list/description of adverse reactions)
Miscellaneous
- (list/description of adverse reactions)
Postmarketing Experience
(Description)
Drug Interactions
- Drug 1
- Drug 2
- Drug 3
- Drug 4
- Drug 5
Drug 1
(Description)
Drug 2
(Description)
Drug 3
(Description)
Drug 4
(Description)
Drug 5
(Description)
Use in Specific Populations
Pregnancy
Pregnancy Category (FDA):
(Description)
Pregnancy Category (AUS):
(Description)
Labor and Delivery
(Description)
Nursing Mothers
(Description)
Pediatric Use
(Description)
Geriatic Use
(Description)
Gender
(Description)
Race
(Description)
Renal Impairment
(Description)
Hepatic Impairment
(Description)
Females of Reproductive Potential and Males
(Description)
Immunocompromised Patients
(Description)
Others
(Description)
Administration and Monitoring
Administration
(Oral/Intravenous/etc)
Monitoring
Condition 1
(Description regarding monitoring, from Warnings section)
Condition 2
(Description regarding monitoring, from Warnings section)
Condition 3
(Description regarding monitoring, from Warnings section)
IV Compatibility
Solution
Compatible
- Solution 1
- Solution 2
- Solution 3
Not Tested
- Solution 1
- Solution 2
- Solution 3
Variable
- Solution 1
- Solution 2
- Solution 3
Incompatible
- Solution 1
- Solution 2
- Solution 3
Y-Site
Compatible
- Solution 1
- Solution 2
- Solution 3
Not Tested
- Solution 1
- Solution 2
- Solution 3
Variable
- Solution 1
- Solution 2
- Solution 3
Incompatible
- Solution 1
- Solution 2
- Solution 3
Admixture
Compatible
- Solution 1
- Solution 2
- Solution 3
Not Tested
- Solution 1
- Solution 2
- Solution 3
Variable
- Solution 1
- Solution 2
- Solution 3
Incompatible
- Solution 1
- Solution 2
- Solution 3
Syringe
Compatible
- Solution 1
- Solution 2
- Solution 3
Not Tested
- Solution 1
- Solution 2
- Solution 3
Variable
- Solution 1
- Solution 2
- Solution 3
Incompatible
- Solution 1
- Solution 2
- Solution 3
TPN/TNA
Compatible
- Solution 1
- Solution 2
- Solution 3
Not Tested
- Solution 1
- Solution 2
- Solution 3
Variable
- Solution 1
- Solution 2
- Solution 3
Incompatible
- Solution 1
- Solution 2
- Solution 3
Overdosage
Acute Overdose
Signs and Symptoms
(Description)
Management
(Description)
Chronic Overdose
Signs and Symptoms
(Description)
Management
(Description)
Pharmacology
| |
Methyldopa
| |
| Systematic (IUPAC) name | |
| ? | |
| Identifiers | |
| CAS number | ? |
| ATC code | ? |
| PubChem | ? |
| Chemical data | |
| Formula | ? |
| Mol. mass | ? |
| Pharmacokinetic data | |
| Bioavailability | ? |
| Metabolism | ? |
| Half life | ? |
| Excretion | ? |
| Therapeutic considerations | |
| Pregnancy cat. |
? |
| Legal status | |
| Routes | ? |
Mechanism of Action
(Description)
Structure
(Description with picture)
Pharmacodynamics
(Description)
Pharmacokinetics
(Description)
Nonclinical Toxicology
(Description)
Clinical Studies
Condition 1
(Description)
Condition 2
(Description)
Condition 3
(Description)
How Supplied
(Description)
Storage
There is limited information regarding Methyldopa Storage in the drug label.
Images
Drug Images
{{#ask: Page Name::Methyldopa |?Pill Name |?Drug Name |?Pill Ingred |?Pill Imprint |?Pill Dosage |?Pill Color |?Pill Shape |?Pill Size (mm) |?Pill Scoring |?NDC |?Drug Author |format=template |template=DrugPageImages |mainlabel=- |sort=Pill Name }}
Package and Label Display Panel
{{#ask: Label Page::Methyldopa |?Label Name |format=template |template=DrugLabelImages |mainlabel=- |sort=Label Page }}
Patient Counseling Information
(Patient Counseling Information)
Precautions with Alcohol
Alcohol-Methyldopa interaction has not been established. Talk to your doctor about the effects of taking alcohol with this medication.
Brand Names
There is limited information regarding Methyldopa Brand Names in the drug label.
Look-Alike Drug Names
- (Paired Confused Name 1a) — (Paired Confused Name 1b)
- (Paired Confused Name 2a) — (Paired Confused Name 2b)
- (Paired Confused Name 3a) — (Paired Confused Name 3b)
Drug Shortage Status
Drug Shortage
Price
References
The contents of this FDA label are provided by the National Library of Medicine.