Carbidopa / levodopa Side Effects

Medically reviewed by Philip Thornton, DipPharm. Last updated on Oct 21, 2023.

Applies to carbidopa / levodopa: oral capsule extended release, oral tablet, oral tablet disintegrating, oral tablet extended release.

Serious side effects

Along with its needed effects, carbidopa / levodopa may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking carbidopa / levodopa:

More common

• Twitching, twisting, uncontrolled repetitive movements of the tongue, lips, face, arms, or legs

Less common

• Bladder pain
• bloody or cloudy urine
• chest pain
• confusion
• difficult, burning, or painful urination
• discouragement
• feeling sad or empty
• frequent urge to urinate
• inability to move the eyes
• increased blinking or spasms of the eyelid
• irritability
• lack of appetite
• loss of interest or pleasure
• lower back or side pain
• seeing, hearing, or feeling things that are not there
• sticking out of tongue
• tiredness
• trouble concentrating
• trouble in breathing, speaking, or swallowing
• trouble sleeping
• uncontrolled twisting movements of the neck, trunk, arms, or legs
• unusual facial expressions

Incidence not known

• Anxiety
• black, tarry stools
• bluish color
• blurred vision
• changes in skin color
• chest discomfort
• chills
• convulsions
• cough or hoarseness
• dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
• dry mouth
• false beliefs that cannot be changed by facts
• fast, irregular, pounding, or racing heartbeat or pulse
• feelings about hurting oneself or others
• fever with or without chills
• general feeling of tiredness or weakness
• high fever
• hyperventilation
• increased in sexual ability, desire, drive, or performance
• increased interest in sexual intercourse
• increased sweating
• large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
• loss of bladder control
• lower back or side pain
• nausea
• pain
• pain or discomfort in the arms, jaw, back, or neck
• restlessness
• seeing, hearing, or feeling things that are not there
• severe muscle stiffness
• shaking
• sore throat
• sores, ulcers, or white spots on the lips or in the mouth
• swelling of the foot or leg
• swollen glands
• tenderness
• tiredness
• unusual bleeding or bruising
• unusual tiredness or weakness
• unusually pale skin
• vomiting

Other side effects

Some side effects of carbidopa / levodopa may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Less common

• Acid or sour stomach
• back or shoulder pain
• belching
• body aches or pain
• burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
• diarrhea
• difficulty having a bowel movement (stool)
• ear congestion
• headache
• heartburn
• indigestion
• loss of voice
• muscle cramps
• nasal congestion
• runny nose
• sneezing
• stomach discomfort, upset, or pain
• unusual dreams
• weight loss

Incidence not known

• Abdominal or stomach distress
• bad, unusual, or unpleasant (after) taste
• belching
• change in taste
• dark sweat
• double vision
• enlarged pupils
• feeling of warmth
• hair loss or thinning of the hair
• lack or loss of strength
• redness of the face, neck, arms, and occasionally, upper chest
• seeing double
• skin rash, hives or welts, itching

For Healthcare Professionals

Applies to carbidopa / levodopa: enteral suspension, oral capsule extended release, oral tablet, oral tablet disintegrating, oral tablet extended release.

General

The most common adverse reactions reported include nausea, dizziness, headache, insomnia, abnormal dreams, dry mouth, dyskinesia, anxiety, constipation, vomiting, and orthostatic hypotension.^[Ref]

Nervous system

Very common (10% or more): Headache (up to 17%), dyskinesia (up to 16.5%), dizziness (up to 12%)

Common (1% to 10%): Confusion, dystonia, on-off phenomena, hypoesthesia, polyneuropathy, tremor, dysgeusia, bradykinesia

Uncommon (0.1% to 1%): Paresthesia, ataxia, gait disturbance, convulsion

Rare (less than 0.1%): Malignant, neuroleptic syndrome

Frequency not reported: Chorea, somnolence, memory impairment, sense of stimulation

Postmarketing reports: Polyneuropathy^[Ref]

Psychiatric

Very common (10% or more): Anxiety, insomnia, depression (up to 11%)

Common (1% to 10%): Hallucinations, psychosis, abnormal dreams, sleep disorder, agitation, impulsive behavior, sleep attacks

Uncommon (0.1% to 1%): Suicide, dementia, disorientation, euphoric mood, fear

Rare (less than 0.1%): Abnormal thinking

Postmarketing: Suicide attempt, suicidal ideation^[Ref]

Gastrointestinal

Very common (10% or more): Nausea (up to 30%), constipation (up to 22%)

Common (1% to 10%): Dry mouth, constipation, vomiting, hiatal hernia, postoperative ileus, diarrhea, dyspepsia, abdominal distension, dysphagia, flatulence, bitter taste

Uncommon (0.1% to 1%): Salivary hypersecretion

Rare (less than 0.1%): Bruxism, saliva discoloration, glossodynia, hiccups, trismus, burning tongue sensation

Frequency not reported: Heartburn^[Ref]

Cardiovascular

Common (1% to 10%): Ischemic events, orthostatic hypotension, peripheral edema, hypertension, syncope, irregular heart rate, hypotension

Uncommon (0.1% to 1%): Palpitations, phlebitis

Frequency not reported: Chest pain, myocardial infarction^[Ref]

Cardiovascular ischemic events occurred in 2.4% (7 of 289) patients receiving carbidopa-levodopa extended-release capsules compared to 1.1% (1 of 92) of patients receiving placebo in early Parkinson's disease clinical trials. In advanced Parkinson's disease, 0.7 % (3 of 450) patients experienced cardiovascular ischemic events. These patients had a previous history of ischemic heart disease or risk factors for ischemic heart disease.^[Ref]

Dermatologic

Common (1% to 10%): Excessive granulation tissue, rash, contact dermatitis, hyperhidrosis, pruritus

Uncommon (0.1% to 1%): Alopecia, erythema, urticaria

Rare (less than 0.1%): Sweat discoloration, angioedema

Postmarketing reports: Henoch-Schonlein purpura^[Ref]

Local

Very common (10% or more): Insertion site complication, incision site erythema (19%), post-operative wound infection

Common (1% to 10%): Incision site cellulitis, post procedural infection, device dislocation, device occlusion

Uncommon (0.1% to 1%): Postoperative abscess, bezoar, ischemic colitis

Postmarketing reports: Gastric perforation, gastrointestinal perforation, small intestinal ischemia, small intestinal perforation^[Ref]

Insertion site complication was reported in 57% of patients who received this drug compared with 44% of patients who received a PEG-J tube without receiving treatment. The most common adverse reactions associated with naso-jejunal (NJ) insertion were oropharyngeal pain, abdominal distention, abdominal pain, abdominal discomfort, pain, throat irritation, gastrointestinal injury, esophageal hemorrhage, anxiety, dysphagia, and vomiting. The most common adverse reactions associated with PEG-J insertion included upper abdominal pain, duodenal ulcer, duodenal ulcer hemorrhage, erosive duodenitis, erosive gastritis, gastrointestinal hemorrhage, intussusception, peritonitis, post-operative abscess, and small intestine ulcer.^[Ref]

Hypersensitivity

Postmarketing reports: Anaphylactic reaction, bullous lesions^[Ref]

Respiratory

Common (1% to 10%): Upper respiratory tract infection, atelectasis, dyspnea, aspiration pneumonia, oropharyngeal pain

Uncommon (0.1% to 1%): Dysphonia, hoarseness

Rare (less than 0.1%): Abnormal respiration

Frequency not reported: Bizarre breathing pattern^[Ref]

Hepatic

Frequency not reported: Elevated alkaline phosphatases, AST, ALT, LDH, and bilirubin^[Ref]

Renal

Frequency not reported: Elevated serum urea and creatinine^[Ref]

Other

Very common (10% or more): Asthenia, fatigue

Common (1% to 10%): Pyrexia, malaise

Frequency not reported: Hot flashes^[Ref]

Genitourinary

Common (1% to 10%): Urinary tract infection, urinary incontinence, urinary retention

Uncommon (0.1% to 1%): Urinary frequency

Rare (less than 0.1%): Priapism^[Ref]

Hematologic

Common (1% to 10%): Anemia

Uncommon (0.1% to 1%): Leukopenia, thrombocytopenia

Rare (less than 0.1%): Hemolytic anemia

Very rare (less than 0.01%): Agranulocytosis

Frequency not reported: Positive Coombs test, reduced hemoglobin and hematocrit^[Ref]

Metabolic

Very common (10% or more): Decreased weight

Common (1% to 10%): Anorexia, increased weight, vitamin B6 deficiency, vitamin B12 deficiency

Frequency not reported: Elevated blood sugar

Postmarketing reports: Folic acid deficiency^[Ref]

Musculoskeletal

Common (1% to 10%): Back pain, shoulder pain

Uncommon (0.1% to 1%): Muscle cramps, neck pain

Frequency not reported: Muscle twitching, leg pain^[Ref]

Ocular

Uncommon (0.1% to 1%): Blepharospasm, diplopia, optic ischemic neuropathy, blurred vision

Rare (less than 0.1%): Mydriasis, oculogyric crisis, activation of a latent Horner's syndrome^[Ref]

Oncologic

Rare (less than 0.1%): Malignant melanoma^[Ref]

Frequently asked questions

• How long does it take carbidopa levodopa to work?
• How often should carbidopa/levodopa be taken?
• Can carbidopa/levodopa cause high blood pressure?
• What foods should be avoided when taking levodopa?
• Is Rytary better than Sinemet?
• What is the difference between carbidopa, levodopa, and Rytary?
• How long does it take for Rytary to start working?
• How long does Rytary stay in your system?

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.

Medical Disclaimer