Levodopa (Oral)

Overview

The primary treatment target for levodopa is Parkinson's disease, and in milder cases of the disorder, levodopa can be used to manage trembling and shaking. In more severe or more advanced cases, a combination treatment including carbidopa is often prescribed. The effect which this medication has on the body is to improve control of the muscular system, thereby allowing a more normal lifestyle for the patient.

Since one of the triggers for Parkinson's is thought by doctors and scientists to be a deficiency of a naturally produced substance called dopamine, levodopa helps manage this deficiency by turning into dopamine once it reaches the brain. When used in tandem with carbidopa, more of the levodopa medicine actually reaches the brain because carbidopa acts to prevent the natural breakdown of levodopa as it passes through the body en route to the brain. Carbidopa can also lessen the side effects of nausea and vomiting which are sometimes caused by levodopa.

It is usually better for a patient to take levodopa with food since that tends to reduce the sensation of nausea, but it's also advisable to decrease the amount of protein ingested because that acts to decrease the amount of levodopa absorbed by the body. This is a medication whose dosage is universally prescribed on the basis of a patient's reaction to the drug, and the precise degree of severity for the symptoms associated with the disease. Doctors will generally begin with an experimental dosage to observe levodopa's effect on the disease, and then formulate a more accurate treatment plan to accommodate those circumstances.

Condition treated

  • Parkinson's Disease

Type Of Medicine

  • Anti-parkinsonian

Side Effects

In addition to managing the tremors and shaking associated with Parkinson's disease, levodopa may also induce some unwanted side effects in patients. While some patients will experience very few side effects or none at all from using this drug, others may experience more severe side effects. If you should notice any of the side effects listed below, you should contact your doctor and discuss them, especially if they are to such a degree that it makes you very comfortable. One of the first and most important side effects to be on the lookout for is an allergic reaction to levodopa, and this is important because some side effects can actually become life-threatening if not remediated.

The symptoms to look for in an allergic reaction are the following:

  • Severe tightness in the chest, often accompanied by extreme difficulty with breathing
  • Itchiness all around the body
  • Hives and/or rashes appearing on skin surfaces
  • Swelling or puffiness around the eyelids, or on the tongue, lips, and throat
  • Dizziness or lightheadedness, often with the sensation that you are about to faint.

There are a number of other severe side effects which you may experience to a greater or lesser degree when taking levodopa, including the following:

  • Nausea and/or vomiting
  • Loss of appetite
  • Difficulty with sleeping
  • Unusual dreams or nightmares
  • Headaches
  • Dizziness
  • Dark-colored urine
  • Dark-colored saliva
  • Dark-colored sweat
  • Extreme dizziness
  • New uncontrollable movements or worsening of such uncontrollable movements
  • Much greater blinking and twitching of the eyes
  • Vision changes such as double vision or blurry vision
  • Pain all around the eyes
  • Severe stomach pains or cramping
  • Severe abdominal pains or cramping
  • Black and/or tarry stools
  • Vomiting up material that looks like coffee grounds
  • Depression
  • Suicidal thoughts
  • Mood swings
  • Sore throats that persist
  • Unusual bleeding or bruising
  • Unexplained fatigue
  • Tingling or numbness in the hands or feet
  • Pronounced urges such as with gambling or increased desire for sex
  • Unusual stiffness of the muscles
  • Severe disorientation and confusion
  • Profuse sweating
  • Rapid breathing
  • Fast or irregular heartbeat.

There is a possibility that you will experience dizziness or lightheadedness when rising quickly after taking this medication, either from a sitting position or from a reclining position. To reduce the potential for this dizziness, you should make a point of rising slowly after lying down or sitting, or you should take a few moments to dangle your feet over the side of the bed before standing up.

Some patients have reported spontaneous sleeping episodes after taking levodopa, sometimes with no warning signs of drowsiness beforehand. As you might think, this can be an extremely dangerous situation, for instance, if you happen to be driving or operating some kind of machinery. If you experience any kind of increased fatigue or drowsiness when taking levodopa, be sure to not do any driving or machinery operation after taking the medicine, so that you won't cause a danger to yourself or others. It is also known that this drowsiness and spontaneous sleeping can happen to both new patients and those who have been taking levodopa for a very long period of time. This sleep effect is also exacerbated by the consumption of alcohol, which is a known depressant, and which can deepen the effects of any drowsiness or fatigue naturally felt by the body.

There is also a possibility when taking this medication that a serious medical condition known as neuroleptic malignant syndrome can develop in patients, which is characterized by strong fevers, muscle stiffness, irregular heartbeat and profuse sweating. If you notice any of these side effects after taking levodopa, you should contact your doctor immediately, and discuss the symptoms as well as their severity.

Dosage

More so than with most drugs, the dosing of levodopa is strongly contingent upon the specifics of a patient's medical condition, as well as the total reaction of a patient after being treated with levodopa. In general, an initial dosage may be an educated guess on the part of your doctor, with the two factors mentioned above being primary determinants of that dosage level. However, an accurate and appropriate dosage can quickly be arrived at after observing any patient's response to the medication.

  • When using levodopa for the treatment of Parkinson's disease as a standalone medicationĀ ' adults and teenagers should be administered an initial dosage of 250 mg, between two and four times daily, subject to doctor's modification. In most cases, no more than 8000 mg per day will be recommended. Pediatric patients up to age 12 will need to have a specific dosage formulated by the family doctor
  • For a combination treatment with levodopa and carbidopa, managing the effects of Parkinson's disease 'the oral tablet dosage form should be administered to an adult as a single tablet, delivered either three or four times daily, subject to doctor modification. Children and teenagers will need to have a specific dosage calculated for them by the family doctor
  • When using the extended-release tablet formĀ ' adults should be administered a single tablet twice daily, until it is determined that additional medication is needed and approved by the family doctor. Children and teenagers must have an appropriate dosage calculated by the family doctor.

If you should miss a dosage of levodopa, it is allowable to take it as soon as you remember to do so, unless you don't remember until close to the time of your next regularly scheduled dosage. In that situation, it is much better to skip the dosage you missed, and simply wait for the time of the next scheduled dosage. You should not take extra medication, or double your medication just because you are experiencing worse than usual symptoms, and you should also not double up on medication for the sake of getting back on your dosage routine.

Interactions

Interactions between drugs often occur, and when they do, it is likely that they will impart adverse side effects to the patient who is using both of them. It's also possible that interaction between two drugs can cause a decrease in the effectiveness of one or both of them. Since it is not a desirable thing to have these interactions between medications occur, both doctor and patient need to do everything possible to avoid that scenario.

As a patient, you can do your part by preparing a list of all the medications you are currently taking, including over-the-counter drugs, other prescription drugs, vitamins, and herbal supplements, as well as the dosage levels of each of these. When you give this to your doctor, he/she can review the list and make a determination on whether or not there is a potential for any of the drugs on this list to interact with levodopa.

You should also keep a copy of this list to present to a doctor at a healthcare clinic where your primary care doctor is not in residence if you should need to visit such a facility. The same holds true for visiting an emergency room setting, and in either of these two cases, any doctor unknown to you can review your medication list and safely prescribe a treatment program for your condition which does not conflict with any of the other medications you're currently taking.

Some of the drugs most commonly checked by doctors for the potential for interaction with levodopa include those on the list below:

  • Procarbazine
  • Phenelzine
  • Pargyline
  • Tranylcypromine
  • Toloxotone
  • Amisulpride
  • Clorgyline
  • Bromopride
  • Furazolidone
  • Sulpiride
  • Nialamide
  • Moclobemide
  • Methylene blue
  • Isocarboxazid
  • Linezolid
  • Iproniazid
  • Bupropion
  • Fosphenytoin
  • Tyrosine
  • Spiramycin
  • Phenylalanine
  • Metoclopramide
  • Iron
  • Kava
  • Indinavir.

You should not take alcohol when being treated with levodopa, since it can increase the severity of any side effects which you might experience. While on a program of treatment using levodopa, you should either avoid alcohol altogether, or you should take only small amounts. You should also avoid eating large amounts of foods containing high levels of protein, since protein can inhibit the body's absorption of levodopa, thereby diminishing its effectiveness.

In addition to the possibility of interacting with other medications you are taking, levodopa may also interact with certain medical conditions you already have. For this reason, it is important for you to discuss with your family doctor as much of your medical history as you are aware of, especially with regard to the medical conditions on the list below:

  • Stomach ulcers
  • Heart or blood vessel disease
  • Glaucoma
  • Mental illness
  • Melanoma
  • Hormonal problems
  • Liver disease
  • Seizure disorders such as epilepsy
  • Kidney disease
  • Emphysema
  • Bronchitis
  • Asthma
  • Any kind of chronic lung disease
  • Diabetes mellitus.

Warnings

There are certain warnings or precautions which should be taken into account by all patients being treated with levodopa, so as not to worsen any medical conditions you may have, or to trigger new situations. In general, many undesirable situations can be avoided by having a thorough consultation with your doctor prior to being treated with levodopa, so that you can understand the risks versus the benefits of taking this medication.

If you know that you are to have any kind of surgery coming up in the future while being treated with levodopa, you should alert your surgeon or dentist to the fact that you are being treated with this medication, so that any drugs administered during surgery will not conflict with levodopa.

Patients who have diabetes should be aware that levodopa has potential to skew test results for urine sugar or ketones. You should consult with your doctor about the advisability of using any home tests that make use of tablets or the paper strip method.

Some patients taking levodopa have reported extreme dizziness, confusion, or vision which has been notably impacted. Before you do anything like operating machinery or driving a motor vehicle, you should already be aware of how levodopa affects your body, and you should be sure that it does not have the effect of making you drowsy or disoriented.

Patients have reported extreme dizziness or even fainting after rising rapidly from a lying position or from a sitting position when taking levodopa. In some cases, it does help for you to rise more slowly, and it may also help if you've been lying down, to transition yourself to a standing position first, by allowing your legs to dangle over the side of a bed. If neither of these mitigating processes helps in your case, you should talk to your doctor about it.

Patients who take levodopa as a standalone medication, i.e. without the accompanying combination medicine of carbidopa, should be aware that vitamin B6 has a noticeable effect on decreasing the usefulness of levodopa. This is an effect which is not present when levodopa is taken in tandem with carbidopa, so if you are taking levodopa by itself, you should avoid taking vitamins during treatment, especially vitamin B6.

The same can be true for foodstuffs which contain large amounts of pyridoxine, which can also diminish the effectiveness of levodopa. For this reason, you should reduce your intake of such foods as lima beans, meats, peanuts, bananas, egg yolks and whole-grain cereals.

During your program of treatment with levodopa, when you reach the point where the medication is working relatively well, and your body movements become more controllable, you should be careful not to overdo the exertion factor. A number of patients have reported injuries due to falls and slips during this time frame when increased physical activity can become part of your routine.

A better approach is to very gradually increase the level of physical activity so that your body has a chance to adjust itself to each new level of exertion. This is especially important in elderly patients, who are generally more prone to slips and falls.

While no significant research has shown that levodopa has a negative impact on unborn infants, it is still highly advisable that women of childbearing age should consult with the family doctor about the potential for becoming pregnant while being treated with this medication. It is known that levodopa does pass into breast milk and is therefore consumed by a nursing infant, so it is not recommended that pregnant mothers use the breastfeeding method. Mothers should substitute some other form of nourishment for a nursing infant.

Storage

Levodopa should be stored at room temperature in a location which is not subject to any kind of extremes of moisture, direct light, cold temperature, or heat and this medicine should never be frozen. It should be stored in a location well out of the reach of pets and small children, preferably in a spot so high up that it cannot be reached, even with the help of furniture or other assistance.

Levodopa should not be kept in a weekly pill reminder, even though this might be convenient for the patient. Such containers do not usually contain adequate locking mechanisms which can prevent unwanted access, so they constitute a danger to household members, especially younger and more curious ones.

Outdated or expired levodopa should not be kept around the household, but should instead be discarded according to proper disposal methods recommended by your doctor or pharmacist. Lacking this kind of information, you can also check the FDA website, which is maintained for the purpose, regarding the safe disposal of medicines.

Summary

Levodopa is a prescription medication used for the treatment of Parkinson's disease, and is often used in conjunction with another anti-parkinsonian medication called carbidopa. Levodopa is effective in managing the trembling and shaking symptoms which accompany Parkinson's, as it supplies a substance to the brain called dopamine, which is generally lacking for patients bothered by this disease.

When carbidopa is used together with levodopa, it prevents the breakdown of levodopa in the body, so that more of the levodopa can reach the brain as dopamine, and re-supply the deficiency there. The medicine is generally taken orally, and it comes in tablet form. Doctors will determine an appropriate dosage level for any patient based on the specific symptoms exhibited by the patient, as well as the patient's response to the medication.