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Carbidopa, Levodopa

  • Prescription medicine
  • Prescription only
  • Identity checked
  • Sources last checked 2026-09-04

This page shows what was measured, who it was measured in, and what that does not settle.

What Carbidopa, Levodopa does in the body

RNAWiki has not recorded what this substance changes in the body.

What happened in people

RNAWiki has not yet published a reviewed conclusion for this use.

A fixed RNAWiki sentence

Where this came from

Wording RNAWiki always uses, not a finding about this substance.

No reviewed claim names a result for any goal on this record.

No source is stored against this line.

The limit that matters most

Not recorded.

Where it acts
Not recorded.
Kind of result
No result is published, so no kind of result applies yet
Supervision
RNAWiki has not recorded a supervision or regulatory status for this substance.

What the registries record it as

  • The substance registry classes this as chemical.

    FDA substance registry · MNX7R8C5VO · read 2026-08-29

  • The label declares 2 active ingredients: carbidopa and levodopa.

    Recorded product composition

Where each sentence above came from

No plain explanation of what this changes is stored.

No recorded use is stored in reader language.

No statement of the main limit is recorded.

The four opening statements run to 26 words.

Words this page uses

Four words worth knowing first

Chosen from what this page shows, with each one explained before the word it depends on.

Formulation

A formulation is the exact made-up form a substance comes in.

A picture of it, and where the picture fails

It is like the difference between a whole bean and instant coffee.

Where that stops being true. Coffee tastes different. A formulation can change how much reaches the blood.

What people get wrong. Two products with the same name are assumed to behave the same. They often do not.

The specific composition and physical form of a product, including salt, excipients and release profile.

What happened in peopleRead from sources, not yet reviewed

What happened in people

Each card is one study: the exact question it asked, who was in it, and whether it showed what it set out to show.

Time to First Occurrence of Dyskinesia

The study did not show it

Who was studied
NCT00099268
How many people
747
Study design
Phase 3
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Result not recorded on this page
Repeated elsewhere
Unreplicated

What this does not prove. A study that did not show an effect does not show that no effect exists anywhere.

The limits of this study, and where it came from

Main limit. No limitation is recorded for this study.

How far it carries. This study is recorded from the curated record, not from the registry match.

Form and route.

Interval reported. Not recorded in this summary

Written into the record, not signed off as a reviewed claim.

  • openFDA Drugs@FDA · a recorded source, not a stored snapshot
  • PubChem PUG-REST · a recorded source, not a stored snapshot
  • openFDA NDC Directory · a recorded source, not a stored snapshot
  • Europe PMC · a recorded source, not a stored snapshot

Mean Change From Baseline in "Good on" Time Per Day at Week 20/Early Termination (ET)

The study did not show it

Who was studied
NCT03670953
How many people
630
Study design
Phase 3
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Result not recorded on this page
Repeated elsewhere
Unreplicated

What this does not prove. A study that did not show an effect does not show that no effect exists anywhere.

The limits of this study, and where it came from

Main limit. No limitation is recorded for this study.

How far it carries. This study is recorded from the curated record, not from the registry match.

Form and route.

Interval reported. Not recorded in this summary

Written into the record, not signed off as a reviewed claim.

  • openFDA Drugs@FDA · a recorded source, not a stored snapshot
  • PubChem PUG-REST · a recorded source, not a stored snapshot
  • openFDA NDC Directory · a recorded source, not a stored snapshot
  • Europe PMC · a recorded source, not a stored snapshot

Change From Baseline in the Sum of UPDRS Part II + UPDRS Part III

The study did not show it

Who was studied
NCT01096186
How many people
617
Study design
Phase 3
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Result not recorded on this page
Repeated elsewhere
Unreplicated

What this does not prove. A study that did not show an effect does not show that no effect exists anywhere.

The limits of this study, and where it came from

Main limit. No limitation is recorded for this study.

How far it carries. This study is recorded from the curated record, not from the registry match.

Form and route.

Interval reported. Not recorded in this summary

Written into the record, not signed off as a reviewed claim.

  • openFDA Drugs@FDA · a recorded source, not a stored snapshot
  • PubChem PUG-REST · a recorded source, not a stored snapshot
  • openFDA NDC Directory · a recorded source, not a stored snapshot
  • Europe PMC · a recorded source, not a stored snapshot

Change From Baseline in the Total Hours of Awake Time/Day Spent in the OFF State at Week 12

The study did not show it

Who was studied
NCT01968031
How many people
613
Study design
Phase 3
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Result not recorded on this page
Repeated elsewhere
Unreplicated

What this does not prove. A study that did not show an effect does not show that no effect exists anywhere.

The limits of this study, and where it came from

Main limit. No limitation is recorded for this study.

How far it carries. This study is recorded from the curated record, not from the registry match.

Form and route.

Interval reported. Not recorded in this summary

Written into the record, not signed off as a reviewed claim.

  • openFDA Drugs@FDA · a recorded source, not a stored snapshot
  • PubChem PUG-REST · a recorded source, not a stored snapshot
  • openFDA NDC Directory · a recorded source, not a stored snapshot
  • Europe PMC · a recorded source, not a stored snapshot

Fugl-Meyer-Motor Assessment Score (FMMA)

The study did not show it

Who was studied
NCT03735901
How many people
610
Study design
Phase 3
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Result not recorded on this page
Repeated elsewhere
Unreplicated

What this does not prove. A study that did not show an effect does not show that no effect exists anywhere.

The limits of this study, and where it came from

Main limit. No limitation is recorded for this study.

How far it carries. This study is recorded from the curated record, not from the registry match.

Form and route.

Interval reported. Not recorded in this summary

Written into the record, not signed off as a reviewed claim.

  • openFDA Drugs@FDA · a recorded source, not a stored snapshot
  • PubChem PUG-REST · a recorded source, not a stored snapshot
  • openFDA NDC Directory · a recorded source, not a stored snapshot
  • Europe PMC · a recorded source, not a stored snapshot

Efficacy of 3 BIA 9-1067 (5 mg, 25 mg, and 50 mg) Compared With 200 mg of Entacapone or Placebo,

The study did not show it

Who was studied
NCT01568073
How many people
600
Study design
Phase 3
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Result not recorded on this page
Repeated elsewhere
Unreplicated

What this does not prove. A study that did not show an effect does not show that no effect exists anywhere.

The limits of this study, and where it came from

Main limit. No limitation is recorded for this study.

How far it carries. This study is recorded from the curated record, not from the registry match.

Form and route.

Interval reported. Not recorded in this summary

Written into the record, not signed off as a reviewed claim.

  • openFDA Drugs@FDA · a recorded source, not a stored snapshot
  • PubChem PUG-REST · a recorded source, not a stored snapshot
  • openFDA NDC Directory · a recorded source, not a stored snapshot
  • Europe PMC · a recorded source, not a stored snapshot
What we know
RNAWiki holds 6 written-up human studies for this substance, each with the question it asked.
How we know it
Each card names the study, the number of people and what the study set out to measure.
What this does not prove
These summaries were written by a person and have not been signed off as reviewed claims.
Why it matters
A study that failed is as informative as one that worked, and both are here.
What we still do not know
No reviewed claim exists, so no exact population, effect size or interval is published yet.

What is missing or unclearRead from sources, not yet reviewed

Were people like you studied?

RNAWiki cannot tell whether a study fits you. It can show who was in it, and where the result stops carrying.

Who was studied

No description of who was studied is recorded.

Who is missing from the studies

  • Which groups were under-represented in the studies has not been recorded for this substance. Pregnancy, breastfeeding, children, older adults, and people with liver or kidney conditions are commonly excluded from trials; nothing here says whether they were.

Where the result stopped carrying

  • This is a scope explorer, not a diagnosis engine.
  • It shows who was studied so you can see whether people similar to you were included.

RNAWiki cannot tell whether a study fits you. It can show who was in it.

What it would be like to takeRead from sources, not yet reviewed

Why it might seem to do nothing

A real effect and a noticed effect are different things. These are the recorded reasons the two come apart.

It was studied in different people

The people in the studies were not much like the reader.

On this record: Which groups were under-represented in the studies has not been recorded for this substance. Pregnancy, breastfeeding, children, older adults, and people with liver or kidney conditions are commonly excluded from trials; nothing here says whether they were.

A different form was studied

The studied form is not the form on the shelf.

On this record: This record is linked to 2 related forms. Evidence does not carry across all of them.

The evidence may simply be wrong

Small early studies often do not hold up.

On this record: RNAWiki has not yet published a reviewed conclusion for this use.

Other reasons RNAWiki checked and found nothing for (10)
It was studied for a different goal
The studies measured something else entirely. Nothing in this record points to this reason.
There was nothing to correct
Where a level is already normal, topping it up may change nothing. Nothing in this record points to this reason.
Something else had to happen too
In the studies it was paired with training, a diet or another treatment. Nothing in this record points to this reason.
The change is too small to feel
A real change can still sit below what a person notices. Nothing in this record points to this reason.
Day-to-day swing hides it
Sleep, food, stress and time of day move most numbers more than this would. Nothing in this record points to this reason.
Not enough time yet
The studies ran longer than the person has waited. Nothing in this record points to this reason.
It was not taken as studied
Missed days change the result, and studies count them. Nothing in this record points to this reason.
Something else changed at the same time
Two changes at once cannot be told apart afterwards. Nothing in this record points to this reason.
The product may not be what it says
Contents of a sold product are not always what the label states. Nothing in this record points to this reason.
No recorded reason
RNAWiki has nothing stored that would explain it. Nothing in this record points to this reason.

None of these is a reason to take more. Taking more is not a step this page ever suggests.

What it would be like to takeRead from sources, not yet reviewed

What taking it involves

The recorded facts about getting hold of it and using it. Nothing here is a suggestion about what you should do.

How it is supplied

Prescription only

Quoted from a source

Where this came from

Copied from a source RNAWiki stored, with the source named.

Read from the recorded approval status.

No source is stored against this line.

Form and route

Not recorded.

Nothing recorded

Where this came from

RNAWiki holds nothing here and says so rather than guessing.

No form or route is recorded.

No source is stored against this line.

Who oversees it

RNAWiki has not recorded a supervision or regulatory status for this substance.

Quoted from a source

Where this came from

Copied from a source RNAWiki stored, with the source named.

No register row and no identity class settled the question.

No source is stored against this line.

What is in the pack

Not recorded.

Nothing recorded

Where this came from

RNAWiki holds nothing here and says so rather than guessing.

Nothing is recorded about product quality.

No source is stored against this line.

Where it is registered

Regulatory records are listed in the technical disclosure at the foot of this page.

Counted from records

Where this came from

A count of rows RNAWiki holds. It describes our records, not your body.

Register entries are stored per jurisdiction and shown with their dates.

No source is stored against this line.

Why people stop

Not recorded.

Nothing recorded

Where this came from

RNAWiki holds nothing here and says so rather than guessing.

No record of why people stopped taking it is stored for this substance.

No source is stored against this line.

What it would be like to takeNothing found in the sources checked

What can go wrong

Sorted by where each line came from. A regulator's label and a report somebody sent in are not the same kind of fact.

Nothing found in the sources checked

No harm is recorded against this substance in the sources RNAWiki checked. Finding nothing is not the same as showing there is nothing.

The sources listed were searched and held nothing. That is not the same as nothing existing.

Over a long time. No completed tested study window is recorded, so long-term effects are not established by the registry record.

Groups the studies covered thinly. Which groups were under-represented in the studies has not been recorded for this substance. Pregnancy, breastfeeding, children, older adults, and people with liver or kidney conditions are commonly excluded from trials; nothing here says whether they were.

What is missing or unclearRead from sources, not yet reviewed

Does the exact form matter?

Evidence belongs to the exact thing that was tested. A different salt, a different mixture or a different preparation is a different question.

The form that was studied

Not recorded.

Nothing recorded

Where this came from

RNAWiki holds nothing here and says so rather than guessing.

The exact form studied is not recorded.

No source is stored against this line.

What is sold

Not recorded.

Nothing recorded

Where this came from

RNAWiki holds nothing here and says so rather than guessing.

Nothing further is recorded about which forms are sold.

No source is stored against this line.

What is recorded as being sold

  • 1 published label names it as an active ingredient. None of them describes this substance alone, so no label text on this page can be attributed to it rather than to a combination.

    US prescribing information · 39d79ade-8ee0-40ba-9fdd-13045b8ddbdf · read 2026-08-29

  • Those labels are classed as human prescription drug.

    US prescribing information · 39d79ade-8ee0-40ba-9fdd-13045b8ddbdf · read 2026-08-29

  • 57 marketed supplement labels list this ingredient, classed as botanical, non-nutrient/non-botanical, other combinations and vitamin.

    NIH Dietary Supplement Label Database · 208639 · read 2026-08-29

  • Those labels carry all other, no claim and nutrient claims. A claim of that kind is written by the manufacturer and is not assessed by any regulator, so its presence says nothing about whether it is true.

    NIH Dietary Supplement Label Database · 208639 · read 2026-08-29

  • Carbidopa-levodopa is oral at HOW SUPPLIED Carbidopa and levodopa tablets USP 10 mg/100 mg are light blue to blue, speckled, round, uncoated tablets, debossed with “Λ” on one side and plain on other., recorded as fda label in effect 2025-01-29 in the United States.

    US prescribing information · 2cdca970-f077-3a80-e063-6294a90ab335 · read 2026-08-30

  • Recorded price in US: 0.06748–0.10936 USD per one unit as the pricing file counts it — a tablet, capsule, patch or single item, across 66 priced products whose strengths and pack forms differ, as of 2026-08-26, paid by retail pharmacies buying the product, as surveyed by the Centers for Medicare & Medicaid Services. It is not a list price, an insurance price, or what anyone pays at a counter..

    Recorded source · 2026-08-26 · read 2026-08-28

Evidence carries across two names for one substance. It does not carry across a salt, a mirror form or a mixture.

Names and forms linked to this record

  • Contains

    Levodopa

    Evidence on this page does not automatically apply to this one.

  • Contains

    Carbidopa Anhydrous

    Evidence on this page does not automatically apply to this one.

What it would be like to takeRead from sources, not yet reviewed

What you could measure

This one is decided with a clinician, so this section holds questions to ask rather than a plan to run.

RNAWiki could not confidently classify this substance, so no self-experiment plan is offered.

Questions worth asking

  • Which of the trials of Carbidopa, Levodopa studied people like me?
  • What was measured, and for how long?
  • Was the result a laboratory value or a health outcome?
  • What would we watch for, and when would we stop?

Tracking can show whether something changed for you. It cannot show what caused it.

RNAWiki records evidence. It does not say whether this substance is right for you.

What is missing or unclearRead from sources, not yet reviewed

What nobody knows yet

Open questions, each with why it is open and what would close it.

Missing populations

Which groups were under-represented in the studies has not been recorded.

Why it matters. Recorded by the evidence model as a gap on this record.

What would answer it

A study that measures it, and a reviewer to sign it off.

Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.

Missing long-term data

No completed tested study window is recorded.

Why it matters. Recorded by the evidence model as a gap on this record.

What would answer it

A study that measures it, and a reviewer to sign it off.

Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.

No reviewed conclusion

RNAWiki has not yet published a reviewed conclusion for this use.

Why it matters. Recorded by the evidence model as a gap on this record.

What would answer it

A study that measures it, and a reviewer to sign it off.

Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.

Missing interaction studies

No interaction was found in the registers checked. Not finding one is not the same as showing there is none.

Why it matters. Recorded by the evidence model as a gap on this record.

What would answer it

A study that measures it, and a reviewer to sign it off.

Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.

Formulation uncertainty

Several salts, forms or products of Carbidopa, Levodopa are recorded. Results from one form may not transfer to another.

Why it matters. Recorded by the evidence model as a gap on this record.

What would answer it

A study that measures it, and a reviewer to sign it off.

Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.

Mechanism not reviewed

No reviewed mechanism story exists for this substance.

Why it matters. Recorded by the evidence model as a gap on this record.

What would answer it

A study that measures it, and a reviewer to sign it off.

Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.

What happened in peopleRead from sources, not yet reviewed

Check any of this yourself

Every line above traced back to the study it came from. This is the technical layer, and the vocabulary changes here.

Where else this substance is registered

FDA substance identifier (UNII)
MNX7R8C5VO
CAS registry number
38821-49-7
PubChem compound
38101
ChEMBL
CHEMBL1201236
ChEBI
3395
RxNorm concept
2019
DrugBank
DB00190

Checks this page had to pass

  • Passed

    Identity resolved

    no open identity hold

  • Passed

    No unresolved merge across substance families

    no quarantine open

  • Not passed

    Every public sentence names a source

    The opening statement carries no source: the record holds neither an explanation nor a recorded use.

  • Not passed

    Trial roles classified for highlighted evidence

    No registered study is classified as testing this substance.

  • Passed

    No internal keys in reader text

    enforced by the copy-contract test over the rendered page

  • Not passed

    Safety mode resolved

    No register row and no identity class settled the question.

  • Passed

    Canonical metadata present

    slug and display name present

What is missing or unclearRead from sources, not yet reviewed

How this medicine reached us

Kept near the foot of the page. A historical event moves up only when it changes something about this substance today.

What the approval register records

  • 3 approved applications cover products containing this substance.

    Drugs@FDA application register · ANDA219989 · read 2026-08-29

  • Marketing status on the register: none (tentative approval).

    Drugs@FDA application register · ANDA219989 · read 2026-08-29

What is missing or unclearRead from sources, not yet reviewed

What to learn next

Ordered by what would most change how you read this page, starting with what is easiest to misunderstand.

This order is fixed in code and does not count clicks or time on the page.

What is not here

9 questions this page could not answer

These sections were prepared and left out because there was nothing to put in them. They are listed rather than hidden, so the gaps in this record are visible.

  • What was measured, goal by goal — found nothing in the sources checked.
  • How close this is to real life — found nothing in the sources checked.
  • The path through the body — found nothing in the sources checked.
  • Felt, measured, or meaningful — found nothing in the sources checked.
  • How long anything takes — found nothing in the sources checked.
  • What it may clash with — found nothing in the sources checked.
  • Other ways to the same goal — found nothing in the sources checked.
  • Claims that go past the evidence — found nothing in the sources checked.
  • What changed on this page — found nothing in the sources checked.

The record as stored

The full record, for auditing

Everything above is built from what is below. This layer keeps the technical vocabulary, record identifiers and every stored row, so a reader who wants to check the page can.

Recorded evidence blocks (6)

29 registered trials of Carbidopa, Levodopa — at which phases?


Registered studies posting no result
19 of 29

29 registered studies of Carbidopa, Levodopa: 10 phase2, 9 phase4, 7 phase1, 4 na, 1 na or unstated. CLINICALTRIALS_SNAPSHOT · 2026-09-01

101 with a PubMed record

Show the evidence
  • phase2
    10
  • phase4
    9
  • phase1
    7
  • na
    4
  • na or unstated
    1
  • completed
    16
5 more recorded rows
  • terminated
    4
  • withdrawn
    4
  • active not recruiting
    2
  • recruiting
    2
  • unknown
    1

recorded 2026-09-01 · last checked 2026-09-04

7 of Carbidopa, Levodopa's trials stopped: accrual/recruitment, funding/business, sponsor decision unspecified?


accrual/recruitment (4), funding/business (1) and sponsor decision unspecified (2): Carbidopa, Levodopa's stop wording, clustered. CLINICALTRIALS_SNAPSHOT · 2026-09-01

"Business decision brand strategy; no patients enrolled"; 7 of 29 registered studies

Show the evidence

Trial

  • NCT00601978
    withdrawn; "Business decision brand strategy; no patients enrolled"
  • NCT03451500
    terminated; "Lack of funding required for enrollment to reach statistical significance."
  • NCT03761030
    terminated; "The project end date was reached prior to the full sample enrollment"
  • NCT04493320
    terminated; "Study terminated by sponsor (NIMH)"
  • NCT04650217
    terminated; "Study terminated by sponsor (NIMH)"
  • NCT04742348
    withdrawn; "COVID-19 and expiration of funding"
  • 1 further recorded trial NCT05087914
    withdrawn; "Study was not started, therefore recruitment did not happen"

recorded 2026-09-01 · last checked 2026-09-04

Human studies of Carbidopa, Levodopa used Carbidopa-Levodopa, 25 Mg-100 Mg Oral Tablet — over how long?


Human studies of Carbidopa, Levodopa used "Carbidopa-Levodopa, 25 Mg-100 Mg Oral Tablet". ClinicalTrials.gov · 2026-09-01

3 recorded entries; human; also "Carbidopa-Levodopa 25 Mg-100 Mg Oral Tablet", "Carbidopa-Levodopa (100mg/25mg):"

Show the evidence

human

  • NCT03023059
    Carbidopa-Levodopa, 25 Mg-100 Mg Oral Tablet
  • NCT04590612
    Carbidopa-Levodopa 25 Mg-100 Mg Oral Tablet
  • NCT05087914
    Carbidopa-Levodopa (100mg/25mg):

recorded 2026-09-01 · last checked 2026-09-04

Which running trial of Carbidopa, Levodopa could settle function?


NCT02994719 measures Gait speed, reading out 2027-07-07.

1 open trial; n 120; "Gait Analysis in Neurological Disease"

Show the evidence
  • Trial NCT02994719
    "Gait Analysis in Neurological Disease"; n 120; "Gait speed"; 2027-07-07

Which 7 trials of Carbidopa, Levodopa posted no result?


Posted no result
7 of 7 completed trials
Registrations
NCT00129181, NCT00914602, NCT02812394, NCT00223691, NCT03496870 and NCT03761004, and 1 more
Completion dates
oldest 2007-01; newest 2022-07-08
Show the evidence

Trial

  • NCT00129181
    2007-01
  • NCT00914602
    2010-01
  • NCT02812394
    2016-09
  • NCT00223691
    2017-01
  • NCT03496870
    2018-07-02
  • NCT03761004
    2019-09-05
  • 1 further recorded trial NCT03929068
    2022-07-08

At the median, Carbidopa, Levodopa's trials enrolled 19 people — anything larger?


Median enrolment
19
Largest enrolment
389
Registered trials counted
29
Where it is registered
Identifiers, relations and other names

The exact record

ChEMBL id
CHEMBL1201236
PubChem CID
38101
CAS number
38821-49-7
RxCUI
2019
InChIKey
TZFNLOMSOLWIDK-JTQLQIEISA-N

Relations

Trade name
Carbidopa and Levodopa
Sources (4)

Sources

  • ChEMBL 37 chembl ·
  • CLINICALTRIALS_SNAPSHOT COMBO:{K1:46627O600J,K1:KR87B45RGH} ·
  • ClinicalTrials.gov clinicaltrials.gov ·
  • Drugs@FDA COMBO:{K1:46627O600J,K1:KR87B45RGH} ·

ChEMBL 37 — CC BY-SA 3.0 Unported · ClinicalTrials.gov — US Government work · mixed register set; per-register licences in docs/specs/corpus-20k-sources.md

How these records are assembled · Which registers were checked

Index-quality checks
  • identity passed: no open identity hold
  • required summary fields resolved: 3 required field(s) not terminal: Best-supported result, Biggest unanswered question, Human evidence
  • public claims reviewed: 0 reviewed claim(s); drafts are never rendered
  • source coverage passed: 4 source rows
  • no critical contamination: no quarantine open
  • canonical metadata passed: slug and display name present
  • no raw internal fields: enforced by the copy-contract test over the rendered page

This is a record of evidence. It is not medical advice, and it does not say this substance suits you. Nothing here says any substance on RNAWiki is appropriate for a child.