Comtan

Comtan is a prescription medication that is used in combination with the medications levodopa and carbidopa to treat symptoms of Parkinson's disease. Comtan belongs to a group of drugs called COMT inhibitors. It works to prevent the breakdown of levodopa and carbidopa and allows more of these medications to reach the brain. 

This medication comes in tablet form and is taken with every dose of levodopa and carbidopa, up to 8 times a day, with or without food. 

Common side effects of Comtan include diarrhea, nausea, change in the color of urine, and movements you cannot control.

Comtan can also cause drowsiness and dizziness. Do not drive or operate heavy machinery until you know how Comtan affects you.

Comtan is a prescription medication that is used in combination with the medications levodopa and carbidopa to treat the symptoms of Parkinson's disease, a disorder of the nervous system that affects movement.

This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.

• Novartis Pharmaceuticals Corporation

• Orion Corporation

Serious side effects have been reported with Comtan. See the "Comtan Precautions" section.

Common side effects of Comtan include the following:

• diarrhea
• nausea
• stomach pain
• dizziness
• drowsiness
• movements you cannot control
• change in the color of urine

This is not a complete list of Comtan side effects. Ask your doctor or pharmacist for more information.

Tell your doctor if you have any side effect that bothers you or that does not go away.

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

Tell your doctor about all the medicines you take, including prescription and non-prescription medicines, vitamins, and herbal supplements. Especially tell your doctor if you take:

• Alcohol and other sedating medications such as:
  • barbiturate medications including butalbital, pentobarbital (Nembutal), phenobarbital (Luminal)
  • benzodiazepine medications including clonazepam (Klonopin), diazepam (Diastat), lorazepam (Ativan), midazolam (Versed), alprazolam (Xanax), temazepam (Restoril)
  • hypnotic medications including eszopiclone (Lunesta), zeleplon (Sonata), zolpidem (Ambien)
  • first generation antihistamine medications including diphenhydramine (Benedryl), doxylamine (Diclectin), promethazine (Phenergan), hydroxyzine (Vistaril), chlorpheniramine (Chlor-Trimeton)
  • muscle relaxant medications including baclofen (Lioresal), carisoprodol (Somadril), cyclobenzaprine (Flexeril), methocarbamol (Robaxin), tizanidine (Zanaflex), gabapentin (Neurontin), pregabalin (Lyrica)
  • opioid pain relieving medications including tramadol (Ultram), morphine (MS Contin), hydromorphone (Dilaudid), oxymorphone (Opana), oxycodone (Oxycontin), hydrocodone (Vantrela), fentanyl (Duragesic), codeine, meperidine (Demerol)
  • antidepressant medications including amitriptyline (Elavil), trazodone (Oleptro), mirtazapine (Remeron), doxepin (Sinequan), nortriptyline (Pamelor), nefazodone (Serzone)
  • antipsychotic medications including olanzapine (Zyprexa), clozapine (Clozaril), haloperidol (Haldol), fluphenazine (Prolixin), quetiapine (Seroquel), prochlorperazine (Compazine)
• Medications metabolized by the enzyme COMT such as:
  • alpha-methyldopa
  • apomorphine
  • bitolterol
  • dobutamine
  • dopamine
  • epinephrine 
  • isoetherine
  • isoproterenol
  • norepinephrine
• Monoamine oxidase inhibitors such as
  • isocarboxazid (Marplan)
  • phenelzine (Nardil)
  • tranylcypromine (Parnate)
  • selegiline (Emsam, Eldepryl, Zelapar)
  • rasagiline (Azilect)
• Pipamperone

Serious side effects have been reported with Comtan including the following: 

• Hypotension: also known as low blood pressure. This may cause you to feel faint, lightheaded, or dizzy. Specifically, orthostatic hypotension can happen when you stand up from sitting or lying down.  Lie down if you feel faint or dizzy and call your healthcare provider right away. 

• ​Psychotic behavior: new or worsening mental status and behavioral changes can happen after starting or increasing the dose. Patients with a major psychotic disorder should ordinarily not be treated with Comtan because of the risk of worsening psychosis. Symptoms may include:
  • ​Impulsive and Compulsive Behavior: intense urges to gamble, spend money, increased sexual urges, etc. 
  • Abnormal thinking: paranoid ideas, delusions, hallucinations, confusion, disorientation, aggressive behavior, agitation, delirium.
  • Severe psychotic behavior
• Diarrhea and colitis (inflammed colon): moderate to severe, watery, and nonbloody diarrhea. At times may occur with dehydration, abdominal pain, weight loss and hypokalemia (low potassium). In most cases, diarrhea and other colitis related symptoms resolved or significantly improved when Comtan was stopped. Tell your healthcare provider right away if you have severe or worsening diarrhea. 
• Dyskinesia: This is the inability to control muscular movements, or the presence of muscle spasms, lack of coordination, or repetitive motions. Comtan can worsen preexsisting muscle control.
• Rhabdomyolysis: This occurs when muscle tissue is damaged and leads to the release of muscle fiber contents into the blood. These muscle fibers are harmful to the kidney and often cause kidney damage.
• Concomitant Use: Use of non-selective MAOI inhibitors (eg, phenelzine, tranylcypromine) should generally be avoided 
• Dermatologic: Increased risk of developing melanoma; monitoring recommended 
• Hepatic: Use with caution in patients with biliary obstruction or hepatic impairment
• Neurologic: Falling asleep during activities of daily living, with or without somnolence, has been reported; discontinuation is recommended if this occurs
• Neurologic: Abrupt discontinuation or dose reduction may result in a symptom complex similar to neuroleptic malignant syndrome 
• Renal: Retroperitoneal fibrosis has been reported with ergot-derived dopaminergic therapy; may resolve with discontinuation 
• Respiratory: Pulmonary fibrosis has occurred with entacapone, and other fibrotic complications (including retroperitoneal fibrosis, pulmonary infiltrates, pleural effusion, and pleural thickening) have been reported with ergot-derived dopaminergic therapies; may resolve with discontinuation

Tell your healthcare provider right away if you have some or all of the listed symptoms.

Comtan can cause drowsiness. Do not drive or operate heavy machinery until you know how Comtan affects you.

Do not take Comtan if you are allergic to Comtan or to any of its ingredients.

Medications can interact with certain foods. In some cases, this may be harmful and your doctor may advise you to avoid certain foods. In the case of Comtan, there are no specific foods that you must exclude from your diet when receiving this medication.

Before taking Comtan, tell your doctor about all of your medical conditions. Especially tell your doctor if you:

• are allergic to Comtan or to any of its ingredients
• have low blood pressure 
• have liver problems
• have heart problems
• have a history of a psychotic disorder
• are pregnant or plan to become pregnant
• are breastfeeding or plan to breastfeed

Tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements.

Tell your doctor if you are pregnant or plan to become pregnant.

The FDA categorizes medications based on safety for use during pregnancy. Five categories - A, B, C, D, and X, are used to classify the possible risks to an unborn baby when a medication is taken during pregnancy.

Comtan falls into category C. There are no well-controlled studies that have been done in pregnant women. Comtan should be used during pregnancy only if the possible benefit outweighs the possible risk to the unborn baby.

Tell your doctor if you are breastfeeding or plan to breastfeed.

It is not known if Comtan crosses into human milk. Because many medications can cross into human milk and because of the possibility for serious adverse reactions in nursing infants with use of this medication, a choice should be made whether to stop nursing or stop the use of this medication. Your doctor and you will decide if the benefits outweigh the risk of using Comtan. 

Take Comtan exactly as prescribed.

Comtan comes in tablet form and is taken with each dose of levodopa/carvidopa, up to a maximum of 8 times daily. Comtan may be combined with both the immediate and sustained release forms of levodopa/carvidopa. Comtan should always be administered with levodopa/carvidopa because it has no anti-Parkinsonian effect on its own. 

Comtan may be taken with or without food. 

If you miss a dose, take the missed dose as soon as you remember. If it is almost time for the next dose, skip the missed dose and take your next dose at the regular time. Do not take two doses of Comtan at the same time.

Take this medication exactly as prescribed by your doctor. Follow the directions on your prescription label carefully.

The dosing schedule your doctor recommends may be based on the following:

• other medical conditions you have
• other medications you are taking
• how you respond to this medication
• your age

The recommended dose of Comtan for the treatment of Parkinson's disease is 200 mg by mouth with each levodopa/carvidopa dose, up to a maximum of 8 times daily (maximum daily dose is 1,600 mg per day). Comtan should always be administered with levodopa/carvidopa because it has no anti-Parkinsonian effect on its own. 

If you take too much Comtan, call your healthcare provider or local Poison Control Center, or seek emergency medical attention right away.

• Store Comtan at room temperature (25°C or 77°F). 
• Comtan should always be administered with levodopa and carvidopa because it has no anti-Parkinsonian effect on its own. 
• Do not suddenly stop Comtan without talking to your healthcare provider. Suddenly stopping Comtan may cause worsening of Parkinson's disease. 
• Keep this and all medicines out of the reach of children.