LEVODOPA+BENSERAZIDE
Special instructions Adverse reactions from the gastrointestinal tract, which are possible at the initial stage of treatment, are largely eliminated if you take the drug Levodopa/Benserazide-Teva with a small amount of food or liquid, as well as a slower dose increase. The use of Levodopa/Benserazide-Teva for the treatment of iatrogenic extrapyramidal syndrome and Huntington's chorea is not recommended.
In patients with a history of gastrointestinal ulcers, seizures and osteomalacia, it is necessary to regularly monitor the relevant indicators. During treatment, indicators of liver function, kidney function, and blood count should be monitored. In patients with a history of coronary artery disease, myocardial infarction, or cardiac arrhythmias, it is necessary to regularly monitor the ECG.
Patients with a history of orthostatic hypotension should be under medical supervision, especially at the beginning of treatment.
In patients with diabetes mellitus, blood glucose concentrations should be monitored frequently and the dose of oral hypoglycemic agents should be adjusted.
Cases of sudden onset of sleep have been reported with the use of Levodopa/Benserazide-Teva. Patients should be informed about the possibility of sudden sleep onset.
When using the drug Levodopa/Benserazide-Teva, the risk of developing malignant melanoma increases, and therefore the use of the drug in patients with malignant melanoma, incl. history, not recommended. The use of Levodopa/Benserazide-Teva, especially in high doses, increases the risk of developing compulsive disorders.
Before general anesthesia, Levodopa/Benserazid-Teva should be taken for as long a period as possible. An exception is halothane anesthesia. Since the patient receiving the drug may experience fluctuations in blood pressure and arrhythmias during halothane anesthesia, the drug should be discontinued 12–24 hours before surgery. After surgery, treatment is resumed, gradually increasing the dose.
Levodopa/Benserazid-Teva should not be discontinued abruptly. Abrupt withdrawal of the drug can lead to withdrawal syndrome (fever, muscle rigidity, as well as possible mental changes and increased CPK activity in the blood serum) or akinetic crises, which can take a life-threatening form. If such symptoms occur, the patient should be under medical supervision (if necessary, hospitalized) and receive appropriate therapy, which may include repeated use of Levodopa/Benserazide-Teva.
Depression can be a clinical manifestation of the underlying disease (parkinsonism) and can also occur during treatment with Levodopa/Benserazide-Teva. Such patients should be under medical supervision for timely identification of psychiatric adverse reactions.
Some patients with Parkinson's disease have experienced the emergence of behavioral and cognitive disorders as a result of uncontrolled use of increasing doses of the drug, despite the doctor's recommendations and a significant increase in therapeutic doses.
Experience with the use of Levodopa/Benserazide-Teva in people under 25 years of age is limited.
Impact on the ability to drive vehicles and work with equipment.
Patients who experience excessive daytime sleepiness or sudden sleep episodes should avoid driving or operating machinery. If these symptoms occur during treatment with Levodopa/Benserazide-Teva, dose reduction or discontinuation of therapy should be considered. Drug interactions
Pharmacokinetic interactions
With simultaneous use of trihexyphenidyl (m-anticholinergic), the rate, but not the extent, of absorption of levodopa decreases.
Ferrous sulfate reduces the Cmax and AUC of levodopa by 30–50%; these changes are in some cases clinically significant.
When used simultaneously with antacids, the degree of absorption of levodopa/benserazide is reduced by 32%.
Metoclopramide increases the rate of absorption of levodopa.
Pharmacodynamic interactions
Antipsychotics, opioids and antihypertensive drugs containing reserpine inhibit the effect of levodopa/benserazide. If necessary, use the lowest doses of these drugs.
When used concomitantly, pyridoxine may reduce the antiparkinsonian effect of levodopa/benserazide.
Levodopa/benserazide should not be used with non-selective MAO inhibitors. If it is necessary to use levodopa/benserazide in patients receiving irreversible non-selective MAO inhibitors, at least 2 weeks should pass from the moment of stopping the MAO inhibitor before starting the dose. Premature (within 2 weeks after discontinuation) use of levodopa/benserazide after a non-selective MAO inhibitor (eg tranylcypromine) can cause a hypertensive crisis.
Selective MAO type B inhibitors (including selegiline, rasagiline) and selective MAO type A inhibitors (moclobemide) can be used during treatment with levodopa/benserazide. In certain cases, selegiline may increase the effect of levodopa/benserazide without causing a dangerous interaction. It is recommended to adjust the dose of levodopa/benserazide depending on the individual needs of the patient in terms of therapeutic efficacy and tolerability.
The combination of selective MAO inhibitors type B and selective MAO inhibitors type A is equivalent to taking a non-selective MAO inhibitor, therefore this combination should not be used with levodopa/benserazide.
If it is necessary to use antihypertensive drugs during treatment with levodopa/benserazide, the possibility of developing orthostatic hypotension must be taken into account.
Levodopa/benserazide potentiates the effect of sympathomimetics (epinephrine, norepinephrine, isoproterenol, amphetamine), so this combination of drugs should not be used. If simultaneous use is still necessary, then the state of the cardiovascular system should be carefully monitored and, if necessary, reduce the dose of sympathomimetics.
It is possible to use levodopa/benserazide with other antiparkinsonian drugs (anticholinergic drugs, amantadine, dopamine receptor agonists), and not only the desired but also the undesirable effects may be enhanced. It may be necessary to reduce the dose of levodopa/benserazide or other drug. When levodopa/benserazide is used concomitantly with a catechol-O-methyltransferase inhibitor, a reduction in the dose of levodopa/benserazide may be necessary.
Since a patient receiving levodopa/benserazide may experience fluctuations in blood pressure and arrhythmias during halothane anesthesia, it is necessary to discontinue the drug 12–48 hours before surgery.
Protein-rich foods may reduce the therapeutic effect of levodopa/benserazide.
Levodopa/benserazide may affect laboratory results of catecholamines, creatinine, uric acid, glucose, alkaline phosphatase, and bilirubin.
An increase in the concentration of urea and creatinine in the blood, a false negative reaction to glucose in the urine when using the glucose oxidase method, and a false positive result from the Coombs test can be detected. Storage conditions
Protected from moisture, at a temperature not exceeding 25 °C.
Shelf life: 2 years.
Well
Side effects. It is known that drugs often increase dopamine, which raises the question: can levadopa be addictive and dependent? Addiction is more likely yes, addiction is most likely no. Amphetamine or Methamphetamine depletes dopamine, and dopa increases its production. Here you have 100 rubles, amphetamine will make you spend it in a few hours, and he doesn’t care what you eat tomorrow, while dopa will spend 50 rubles, but will also force you to get more money somewhere.
But with long-term use, with high dopamine, a loss of receptor sensitivity will begin to occur. A larger dosage will be required to achieve the same effects. If you stop taking the supplement, receptor sensitivity will be restored to normal levels. With drugs it will be necessary to resuscitate the entire dopaminergic system.
You can find the main side effects and contraindications online.
You can take dopa for a long time, but the longer, the lower the dosage. For one-time use or several days - 100-200 mg of pure Levodopa, for long-term use - 50-70 mg.
The half-life is about 1 hour, which allows you to split the dosage into 2-3 doses per day.
special instructions
Taking levodopa before prescribing peripheral dopa decarboxylase inhibitors is discontinued 12 hours in combination with these drugs.
It should be taken into account that foods characterized by a high protein content can lead to a decrease in absorption.
L-Dopa contributes to the deterioration of psychomotor reactions, reduces concentration, which should be taken into account when driving complex mechanisms and vehicles.
Analogues of the drug
Analogues of L-dopa are: Levodopa, Kaldopa, Dopaflex, Doparkin.
Drug interactions
When using L-dopa simultaneously with other medications, the following are observed:
- decreased bioavailability of levodopa with tricyclic antidepressants;
- increased likelihood of developing heart rhythm disorders with drugs of inhalation anesthesia, ditilin, beta-agonists;
- decreased antiparkinsonian effect with reserpine, papaverine, pyridoxine, phenytoin, clozepine, clonidine, m-cholinergic blockers, diazepam, antipsychotic drugs derivatives of thioxanthene, diphenylbutylpiperidine, butyrophenone, phenothiazine;
- worsening side effects with methyldopa;
- increased likelihood of dyskinesias and hallucinations with Li+ drugs;
- circulatory disorders are likely with MAO inhibitors (except for MAO-B inhibitors), it is necessary to stop taking MAO inhibitors for 2 weeks, the cause of the disorders is the accumulation of norepinephrine and dopamine directly under the influence of levodopa, whose inactivation is inhibited by MAO inhibitors and an increased risk of developing tachycardia, increased blood pressure, and agitation , dizziness and facial redness;
- the likelihood of a pronounced decrease in blood pressure with tubocurarine increases.
Contraindications for use
L-dopa has a number of contraindications. Thus, the drug cannot be prescribed by a doctor in cases where at least one of the following factors is present:
- hypersensitivity to its components;
- pregnancy;
- lactation period;
- the patient is a child under 12 years of age.
Also, L-dopa is not prescribed if treatment therapy includes MAO inhibitors.
According to the doctor's decision and with caution, the drug may be taken if:
- diseases of the kidneys, liver, endocrine system, lungs;
- psychosis;
- angle-closure glaucoma and predisposition to it;
- chronic open-angle glaucoma;
- diseases of the heart and blood vessels;
- liver and/or kidney failure;
- melanoma;
- conditions when depression of the central nervous system is observed;
- convulsive seizures;
- bronchial asthma and emphysema;
- gastric ulcer and diseases of the duodenum;
- myocardial infarction (including a history; including in combination with various types of arrhythmia);
- heart rhythm disturbances.
Born of tyrosine
Today it is known that the biochemical precursor of dopamine and all mediators of the catecholamine group in the body is the amino acid tyrosine. The enzyme tyrosine hydroxylase converts tyrosine to levodopa (L-DOPA) through the addition of a hydroxo group (OH). In turn, the enzyme L-DOPA decarboxylase converts levodopa into dopamine, which in turn becomes the precursor of norepinephrine and adrenaline.
Dopamine itself is not able to pass through the blood-brain barrier - a powerful line of defense and control that prevents everything that “floats” in our blood from entering the brain. But levodopa passes it well. This determined its bright pharmacological destiny.
Levodopa is short for L-3,4-dihydroxyphenylalanine (L-dopa). The letter L in the name indicates that we are dealing with a levorotatory isomer of the molecule.
If you haven't dealt with organic chemistry in a while, the phrase "levorotatory isomer" can easily confuse you. But in fact, everything is simple here: most organic molecules have a so-called asymmetric carbon atom - a carbon bonded to four different substituents. Its four neighbors can combine with it in two different ways, which will give two different substances. These substances have the same composition, and in structure they are a mirror image of each other, like the left and right hands. The most interesting thing is that in their pure form, solutions of such substances cause rotation of the plane of polarization of light passing through them in different directions. That's why they are called left-handed and right-handed optical isomers: L- and D-isomers, from the Latin lævus - left and dexter - right (just like the hero of the famous TV series Dexter).
L- and D-isomers most often have slightly different biochemical and pharmacological properties, which is not surprising, because living organisms usually contain only one of the two isomers of each substance.
What to combine with
Dopa becomes dopamine through a single reaction that requires vitamin B6. Therefore, the first thing it is advisable to add to the substance is complex vitamins.
To enhance the effects, dopa is combined with any stimulating compounds, such as caffeine. But here the risk of side effects automatically increases, we start with small dosages.
Light sedatives will cover possible side effects, if necessary. In general, in medicine, too high dopamine is “quenched” by such a group of substances as Neuroleptics.
Side effects from taking L-dopa
Taking L-dopa may cause side effects such as:
- from the gastrointestinal tract (vomiting, nausea, constipation, ulceration of the gastric mucosa, dysphagia, loss of appetite, bleeding in the stomach and intestines, etc.);
- from the central nervous system (dizziness, anxiety, sleep disorders, paranoia, euphoric states, depression, convulsions, manifestations of uncontrolled movements, etc.);
- disorders of the heart and blood vessels (low blood pressure, arrhythmia, tachycardia, orthostatic collapse, etc.);
- disorders of the hematopoietic organs (leukopenia, thrombocytopenia);
- in the form of polyuria, less often – diplopia.
