April 29, 2017
Recommended Topic Related To:


"A new study shows that the incidence of parkinsonism and Parkinson's disease (PD) increased between 1976 and 2005, more than doubling in older men during this period.

The authors believe the rise is not just a result of greater awaren"...



Tasmar Side Effects Center

Medical Editor: John P. Cunha, DO, FACOEP

Last reviewed on RxList 3/14/2016

Tasmar (tolcapone) is an inhibitor of catechol-O-methyltransferase (COMT) used together with carbidopa and levodopa to treat symptoms of Parkinson's disease, such as stiffness, tremors, muscle spasms, and poor muscle control. Tasmar is usually reserved for use only in people who have used carbidopa and levodopa without success in treating their Parkinson's disease. When used with carbidopa and levodopa, Tasmar increases levels of levodopa in the body. Common side effects of Tasmar include nausea, vomiting, unwanted/uncontrolled movements, diarrhea, constipation, headache, drowsiness, trouble sleeping (insomnia), increased number of dreams, increased sweating, dry mouth, gas, abdominal pain, muscle cramps, tiredness, unusual skin changes, dizziness, lightheadedness on standing, cold symptoms (stuffy nose, sneezing, sore throat), confusion, weight loss, agitation, or anxiety.

Treatment with Tasmar should always be initiated at a dose of 100 mg three times daily, always as an adjunct to levodopa/carbidopa therapy. Tasmar may interact with cold or allergy medicine, narcotics, sleeping pills, muscle relaxers, medicine for seizures, depression or anxiety, other Parkinson's medications, apomorphine, blood thinners, desipramine, dobutamine, epinephrine, isoproterenol, or methyldopa. Tell your doctor all medications and supplements you use. During pregnancy, Tasmar should be used only when prescribed. It is unknown if this medication passes into breast milk. Consult your doctor before breastfeeding.

Our Tasmar (tolcapone) Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What is Patient Information in Detail?

Easy-to-read and understand detailed drug information and pill images for the patient or caregiver from Cerner Multum.

Tasmar in Detail - Patient Information: Side Effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have any of these serious side effects:

  • nausea, stomach pain, low fever, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes);
  • feeling like you might pass out;
  • fever, stiff muscles, confusion, and sweating (especially when you first start taking tolcapone);
  • hallucinations;
  • tremors (uncontrolled shaking);
  • tight feeling in your chest, trouble breathing;
  • pain or burning when you urinate;
  • severe or ongoing diarrhea; or
  • muscle pain, tenderness, or weakness with fever or flu symptoms and dark colored urine.

Less serious side effects may include:

  • diarrhea or constipation;
  • dry mouth;
  • headache, tired feeling;
  • unusual skin changes;
  • dizziness, drowsiness;
  • cold symptoms such as stuffy nose, sneezing, sore throat;
  • sleep problems (insomnia), dreaming more than usual; or
  • agitation or anxiety.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Read the entire detailed patient monograph for Tasmar (Tolcapone)

What is Patient Information Overview?

A concise overview of the drug for the patient or caregiver from First DataBank.

Tasmar Overview - Patient Information: Side Effects

SIDE EFFECTS: See also Warning section.

Nausea/vomiting, unwanted/uncontrolled movements, diarrhea, headache, drowsiness, trouble sleeping, increased number of dreams, increased sweating, dry mouth, gas, and abdominal pain may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.

To avoid dizziness and lightheadedness, get up slowly when rising from a sitting or lying position.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication may develop serious side effects, but with frequent visits to your doctor, this risk can be minimized.

Some people taking tolcapone have fallen asleep suddenly during their usual daily activities (such as talking on the phone, driving). In some cases, sleep occurred without any feelings of drowsiness beforehand. This sleep effect may occur anytime during treatment with tolcapone, including up to 1 year after starting the medication. If you experience increased sleepiness or fall asleep during the day, do not drive or take part in other possibly dangerous activities until you have discussed this effect with your doctor. Your risk of this sleep effect is increased by using alcohol or other medications that can make you drowsy. See also Precautions section.

Your urine may change color (such as increased yellow color). This effect is harmless.

Tell your doctor right away if you have any serious side effects, including: easy bleeding/bruising, chest pain, fast/irregular heartbeat, fever, mental/mood changes (such as agitation, confusion, hallucinations), unusual strong urges (such as increased gambling, increased sexual urges), muscle pain/soreness/stiffness/weakness, pain/trouble with breathing.

A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Read the entire patient information overview for Tasmar (Tolcapone)

What is Prescribing information?

The FDA package insert formatted in easy-to-find categories for health professionals and clinicians.

Tasmar FDA Prescribing Information: Side Effects
(Adverse Reactions)


Cases of severe hepatocellular injury, including fulminant liver failure resulting in death, have been reported in postmarketing use. As of May 2005, 3 cases of fatal fulminant hepatic failure have been reported from more than 40,000 patient years of worldwide use. This incidence may be 10- to 100fold higher than the background incidence in the general population. All 3 cases were reported within the first six months of initiation of treatment with TASMAR. Analysis of the laboratory monitoring data in over 3,400 TASMAR-treated patients participating in clinical trials indicated that increases in SGPT/ALT or SGOT/AST, when present, generally occurred within the first 6 months of treatment with TASMAR.

The imprecision of the estimated increase is due to uncertainties about the base rate and the actual number of cases occurring in association with TASMAR. The incidence of idiopathic potentially fatal fulminant hepatic failure (i.e., not due to viral hepatitis or alcohol) is low. One estimate, based upon transplant registry data, is approximately 3/1,000,000 patients per year in the United States. Whether this estimate is an appropriate basis for estimating the increased risk of liver failure among TASMAR users is uncertain. TASMAR users, for example, differ in age and general health status from candidates for liver transplantation. Similarly, underreporting of cases may lead to significant underestimation of the increased risk associated with the use of TASMAR.

During the premarketing development of tolcapone, two distinct patient populations were studied, patients with end-of-dose wearing-off phenomena and patients with stable responses to levodopa therapy. All patients received concomitant treatment with levodopa preparations, however, and were similar in other clinical aspects. Adverse reactions are shown for these two populations combined.

The most commonly observed adverse reactions in the double-blind, placebo-controlled trials (N=892), with a difference in incidence (TASMAR minus Placebo) of at least 5 % or greater in the 100 mg or 200 mg TASMAR- treated groups compared to placebo, were dyskinesia, nausea, diarrhea, anorexia, sleep disorder, vomiting, urine discoloration, somnolence, hallucination, dystonia, and sweating.

Approximately 16% of the 592 patients who participated in the double-blind, placebo-controlled trials discontinued treatment due to adverse reactions compared to 10% of the 298 patients who received placebo. Diarrhea was by far the most frequent cause of discontinuation (approximately 6% in tolcapone patients vs. 1% on placebo).

Adverse Reaction Incidence in Controlled Clinical Studies

Table 4 lists treatment emergent adverse reactions that occurred in at least 1% of patients treated with tolcapone participating in the double-blind, placebo-controlled studies and were numerically more common in at least one of the tolcapone groups. In these studies, either tolcapone or placebo was added to levodopa/carbidopa (or benserazide).

The prescriber should be aware that these figures cannot be used to predict the incidence of adverse reactions in the course of usual medical practice where patient characteristics and other factors differ from those that prevailed in the clinical studies. Similarly, the cited frequencies cannot be compared with figures obtained from other clinical investigations involving different treatments, uses, and investigators. However, the cited figures do provide the prescriber with some basis for estimating the relative contribution of drug and nondrug factors to the adverse reactions incidence rate in the population studied.

Table 4: Summary of Patients With Adverse Reactions After Start of Trial Drug Administration (At Least 1% in TASMAR Group and at Least One TASMAR Dose Group greater than Placebo)

Adverse Reactions Placebo Tolcapone tid
N = 298
100 mg
N = 296
200 mg
N = 298
Dyskinesia 20 42 51
Nausea 18 30 35
Sleep Disorder 18 24 25
Dystonia 17 19 22
Dreaming Excessive 17 21 16
Anorexia 13 19 23
Cramps Muscle 17 17 18
Orthostatic Complaints 14 17 17
Somnolence 13 18 14
Diarrhea 8 16 18
Confusion 9 11 10
Dizziness 10 13 6
Headache 7 10 11
Hallucination 5 8 10
Vomiting 4 8 10
Constipation 5 6 8
Fatigue 6 7 3
Upper Respiratory Tract Infection 3 5 7
Falling 4 4 6
Sweating Increased 2 4 7
Urinary Tract Infection 4 5 5
Xerostomia 2 5 6
Abdominal Pain 3 5 6
Syncope 3 4 5
Urine Discoloration 1 2 7
Dyspepsia 2 4 3
Influenza 2 3 4
Dyspnea 2 3 3
Balance Loss 2 3 2
Flatulence 2 2 4
Hyperkinesia 1 3 2
Chest Pain 1 3 1
Hypotension 1 2 2
Paresthesia 3 1
Stiffness 1 2 2
Arthritis 1 2 1
Chest Discomfort 1 1 2
Hypokinesia 1 1 3
Micturition Disorder 1 2 1
Pain Neck 1 2 2
Burning 0 2 1
Sinus Congestion 0 2 1
Agitation 0 1 1
Bleeding Dermal 0 1 1
Irritability 0 1 1
Mental Deficiency 0 1 1
Hyperactivity 0 1 1
Malaise 0 1 0
Panic Reaction 0 1 0
Tumor Skin 0 1 0
Cataract 0 1 0
Euphoria 0 1 0
Fever 0 1
Alopecia 0 1 0
Eye Inflamed 0 1 0
Hypertonia 0 0 1
Tumor Uterus 0 1 0

Effects of Gender on Adverse Reactions

Female patients may be more likely to develop somnolence than males.

Other Adverse Events Observed During All Trials in Patients With Parkinson's Disease

During these trials, all adverse events were recorded by the clinical investigators using terminology of their own choosing. To provide a meaningful estimate of the proportion of individuals having adverse events, similar types of adverse events were grouped into a smaller number of standardized categories using COSTART dictionary terminology. These categories are used in the listing below.

All reported events that occurred at least twice (or once for serious or potentially serious events), except those already listed above, trivial events and terms too vague to be meaningful are included, without regard to determination of a causal relationship to TASMAR.

Events are further classified within body system categories and enumerated in order of decreasing frequency using the following definitions: frequent adverse events are defined as those occurring in at least 1/100 patients; infrequent adverse events are defined as those occurring in between 1/100 and 1/1000 patients; and rare adverse events are defined as those occurring in fewer than 1/1000 patients.

Nervous System - frequent: depression, hypesthesia, tremor, speech disorder, vertigo, emotional lability; infrequent: neuralgia, amnesia, extrapyramidal syndrome, hostility, libido increased, manic reaction, nervousness, paranoid reaction, cerebral ischemia, cerebrovascular accident, delusions, libido decreased, neuropathy, apathy, choreoathetosis, myoclonus, psychosis, thinking abnormal, twitching; rare: antisocial reaction, delirium, encephalopathy, hemiplegia, meningitis.

Digestive System - frequent: tooth disorder; infrequent: dysphagia, gastrointestinal hemorrhage, gastroenteritis, mouth ulceration, increased salivation, abnormal stools, esophagitis, cholelithiasis, colitis, tongue disorder, rectal disorder; rare: cholecystitis, duodenal ulcer, gastrointestinal carcinoma, stomach atony.

Body as a Whole - frequent: flank pain, accidental injury, abdominal pain, infection; infrequent: hernia, pain, allergic reaction, cellulitis, infection fungal, viral infection, carcinoma, chills, infection bacterial, neoplasm, abscess, face edema; rare: death.

Cardiovascular System - frequent: palpitation; infrequent: hypertension, vasodilation, angina pectoris, heart failure, atrial fibrillation, tachycardia, migraine, aortic stenosis, arrhythmia, arteriospasm, bradycardia, cerebral hemorrhage, coronary artery disorder, heart arrest, myocardial infarct, myocardial ischemia, pulmonary embolus; rare: arteriosclerosis, cardiovascular disorder, pericardial effusion, thrombosis.

Musculoskeletal System - frequent: myalgia; infrequent: tenosynovitis, arthrosis, joint disorder.

Urogenital System - frequent: urinary incontinence, impotence; infrequent: prostatic disorder, dysuria, nocturia, polyuria, urinary retention, urinary tract disorder, hematuria, kidney calculus, prostatic carcinoma, breast neoplasm, oliguria, uterine atony, uterine disorder, vaginitis; rare: bladder calculus, ovarian carcinoma, uterine hemorrhage.

Respiratory System - frequent: bronchitis, pharyngitis; infrequent: cough increased, rhinitis, asthma, epistaxis, hyperventilation, laryngitis, hiccup; rare: apnea, hypoxia, lung edema.

Skin and Appendages - frequent: rash; infrequent: herpes zoster, pruritus, seborrhea, skin discoloration, eczema, erythema multiforme, skin disorder, furunculosis, herpes simplex, urticaria.

Special Senses - frequent: tinnitus; infrequent: diplopia, ear pain, eye hemorrhage, eye pain, lacrimation disorder, otitis media, parosmia; rare: glaucoma.

Metabolic and Nutritional - infrequent: edema, hypercholesteremia, thirst, dehydration.

Hemic and Lymphatic System - infrequent: anemia; rare: leukemia, thrombocytopenia.

Endocrine System - infrequent: diabetes mellitus.

Unclassified - infrequent: surgical procedure.

Drug Abuse And Dependence

Tolcapone is not a controlled substance.

Studies conducted in rats and monkeys did not reveal any potential for physical or psychological dependence. Although clinical trials have not revealed any evidence of the potential for abuse, tolerance or physical dependence, systematic studies in humans designed to evaluate these effects have not been performed.

Read the entire FDA prescribing information for Tasmar (Tolcapone)

Tasmar - User Reviews

Tasmar User Reviews

Now you can gain knowledge and insight about a drug treatment with Patient Discussions.

Here is a collection of user reviews for the medication Tasmar sorted by most helpful. Patient Discussions FAQs

Report Problems to the Food and Drug Administration


You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

WebMD Daily

Get breaking medical news.