Comparison of an orally disintegrating ondansetron tablet with the conventional ondansetron tablet for cyclophosphamide-induced emesis in cancer patients: a multicenter, double-masked study. Ondansetron Orally Disintegrating Tablet Emesis Study Group

Clinical Trial

. 1999 Mar;21(3):492-502.

doi: 10.1016/s0149-2918(00)88304-6.

N Davidson 
¹
, B Rapoport, B Erikstein, B L’Esperance, P Ruff, W Paska, I Miller, P Curtis

Affiliations

Affiliation

• ¹ North Middlesex Hospital, London, United Kingdom.

• PMID:

  10321418

• DOI:

  10.1016/s0149-2918(00)88304-6

Clinical Trial

N Davidson et al.

Clin Ther.

1999 Mar.

. 1999 Mar;21(3):492-502.

doi: 10.1016/s0149-2918(00)88304-6.

Authors

N Davidson 
¹
, B Rapoport, B Erikstein, B L’Esperance, P Ruff, W Paska, I Miller, P Curtis

Affiliation

• ¹ North Middlesex Hospital, London, United Kingdom.

• PMID:

  10321418

• DOI:

  10.1016/s0149-2918(00)88304-6

Abstract

A total of 427 cancer patients receiving cyclophosphamide chemotherapy participated in this multicenter, double-masked, double-dummy, parallel-group, randomized study comparing the antiemetic efficacy and safety of an 8-mg conventional ondansetron tablet (OT, n = 212) taken twice daily with an 8-mg orally disintegrating ondansetron tablet (ODT, n = 215) taken twice daily for 3 days. In the primary efficacy analysis, complete or major control of emesis (0 to 2 emetic episodes) between days 1 and 3 was seen in 80% of OT and 78% of ODT patients. The 90% confidence interval for the differences between treatments was -8.6% to 4.4% (defined interval of equivalence, +/-15%), showing that the formulations were equivalent. In the secondary efficacy analysis, no significant differences were observed in the rates of complete control of emesis (no episodes of emesis) over 3 days (63% and 64% of the respective groups) and on day 1 (84% and 81%, respectively) and in the complete control of nausea over 3 days (37% and 43%, respectively) and on day 1 (59% and 61% of patients, respectively). The taste of ODT was acceptable to the majority of patients (89%) who received it. OT and ODT were both well tolerated. Thus 8 mg ODT twice daily represents a palatable, well-tolerated, and effective antiemetic treatment for the control of cyclophosphamide-induced emesis and nausea and provides equivalent treatment to OT 8 mg twice daily.

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How Often Can I Take Zofran (Ondansetron) When Nauseous?

Written by
Juhi Modi

Medically reviewed by
HaVy Ngo-Hamilton, Pharm. D.
| Jun 13, 2023

If you are experiencing nausea and vomiting after surgery or cancer treatment, such as chemotherapy and radiation, your doctor may prescribe a medication called ondansetron (brand name: Zofran). Please continue reading to learn more about this medicine, including its uses, dosage, frequency of use, drug interactions, and tips on safe use. 

What is ondansetron (Zofran)?

Ondansetron (Zofran, Zofran ODT) is a prescription medication used to prevent nausea and vomiting for cancer patients after chemotherapy and radiation treatment. This medication is also used to treat nausea after surgery. It is available in various dosage forms, including oral tablets (4 mg, 8 mg, and 24 mg), orally disintegrating tablets and oral films (4 mg and 8 mg), oral solution (4 mg/5 mL), and injection vials (2 mg/mL).

These different dosage forms, such as the orally disintegrating tablets, the oral liquid, and the oral film, help lessen the nauseating feeling that may be caused by swallowing a tablet. Some of the uses of ondansetron (Zofran) may not be listed in this article.

How does Zofran work?

Zofran is an antiemetic that belongs to a group of drugs called 5-HT3 receptor antagonists. It works by blocking the action of serotonin, a natural substance in the body that can trigger nausea and initiate a vomiting reflex.

What is the usual dose of Zofran?

The usual dose of ondansetron (Zofran) in adults and children is as follows: 

Adults

• Severe nausea and vomiting due to chemotherapy: a single 24-mg dose to be taken 30 minutes before the start of a single day of highly emetogenic (vomiting-inducing) chemotherapy. 
• Moderate nausea and vomiting due to chemotherapy: An 8-mg dose is administered 30 minutes before the start of chemotherapy, followed by another 8-mg dose 8 hours later. After the completion of chemotherapy, 8 mg of Zofran should be taken every 12 hours for 1 to 2 days.
• Radiation therapy: An 8-mg ondansetron is taken 1-2 hours before radiation therapy. After the first dose, the regimen of 8 mg every 8 hours is recommended depending on the type and the location of radiation.
• Post-operative (after-surgery) nausea and vomiting: 16 mg of ondansetron is to be administered 1 hour before anesthesia.

  Children:

• Age 4 to 11: For moderate nausea and vomiting due to chemotherapy, take 4 mg of ondansetron (Zofran) 30 minutes before the start of chemotherapy, followed by another 4 mg dose given at 4 and 8 hours after the first dose. After the completion of chemotherapy, take 4 mg of ondansetron (Zofran) every 8 hours for 1 to 2 days.
   
• Age 12 to 17: For moderate nausea and vomiting due to chemotherapy, take 8 mg of ondansetron (Zofran) 30 minutes before the start of chemotherapy, followed by another 8 mg dose given 8 hours after the first dose. After the completion of chemotherapy, take 8 mg of ondansetron (Zofran) every 12 hours for 1 to 2 days.

Precautions:

• People with severe liver disease should not take more than 8 mg of ondansetron in a day.
• Zofran is not approved by the FDA to be used during pregnancy. However, there are studies that show Zofran’s safety in treating morning sickness during the first trimester. You should discuss with your doctor if you are pregnant or breastfeeding. 
• Do not give Zofran to children younger than 4 years old. 

Can I take Zofran again after 4 hours?

In some cases, you may take Zofran again after 4 hours. For example, in children, 4 mg or 8 mg of Zofran is given 30 minutes before the start of chemotherapy. (The dose is 4 mg in children between 4 and 11 years of age and 8 mg in children between 12 and 17 years of age.) This is followed by another dose 4 hours later and then one more dose 8 hours after the first dose. The child is then given one dose every 8 hours for 1-2 days after completion of chemotherapy.

Can you take Zofran every 6 hours?

The usual frequency of Zofran dosing in adults is an 8 mg tablet every 8-12 hours or 2-3 times a day. A scenario where you could take it more frequently would be if the dose taken was less than 8mg. Nevertheless, the sum of the doses taken cannot exceed 8 mg within that time frame. You should not take this medicine more often than prescribed, so leave it to your provider to determine your dose frequency. Talk to your doctor or pharmacist if your nausea and vomiting are not controlled with the prescribed dose and frequency of Zofran. 

Why can you only take Zofran every 8 hours? 

You can only take Zofran every 8 hours because clinical trials have shown that ondansetron (Zofran) increases the risk of QT prolongation. This is an abnormality in the heart’s electrical system. The risk of QT prolongation appears to be dose related. For this reason, doctors do not give intravenous (IV) doses of more than 16 mg or advise taking Zofran more often than every 8 hours when at home and without proper monitoring of a patient’s vitals.

What are the risks associated with Zofran use?

Severe allergic reactions

In a small number of people, Zofran can cause severe allergic reactions with signs and symptoms such as difficulty breathing, swelling of the throat, skin rash, and other effects. Stop taking ondansetron (Zofran) and seek immediate medical attention if you experience symptoms while on this medication to control nausea and vomiting after cancer treatment or surgery.

Serotonin syndrome

Patients taking too much ondansetron (Zofran) can develop a serious and potentially life-threatening condition called serotonin syndrome. This occurs due to high serotonin levels in the body. The risk is higher in people taking other drugs that affect serotonin levels, such as lithium, antidepressants, and migraine medications. Symptoms of serotonin syndrome may include sweating, fast heartbeat, nausea and vomiting, muscle spasms, muscle stiffness, blurred vision, confusion, and fever. Seek emergency medical attention immediately if you develop any of these symptoms while on Zofran.

Heart rhythm problems

High doses of ondansetron (Zofran) can increase the risk of heart rhythm problems, also known as arrhythmias. The risk is higher in people with congenital long QT syndrome or a history of QT prolongation. Taking other medications that cause heart rhythm problems, congestive heart failure, and low potassium or magnesium can also lead to an increased risk. Tell your healthcare provider if you have any heart rhythm abnormalities before starting ondansetron. Contact your doctor if you notice signs and symptoms such as chest pain, palpitations, slow heartbeat, or irregular heartbeat.

Masking of intestinal blockage symptoms

When you take ondansetron to treat nausea and vomiting after abdominal surgery or chemotherapy, the medicine can mask some of the symptoms of intestinal blockage and abdominal bloating, which happen to be nausea and vomiting. Tell your healthcare provider if you are not passing gas or stools. 

Risk to people with phenylketonuria

People with a rare disorder called phenylketonuria cannot break down an amino acid called phenylalanine. High levels of phenylalanine in the body can cause serious health problems. The orally disintegrating tablet of ondansetron (Zofran ODT) contains phenylalanine. Needless to say, consult your doctor before starting Zofran ODT if you have phenylketonuria.

Tips on the safe use of ondansetron (Zofran)

• Give your doctor or pharmacist a complete list of your medications, including prescription drugs, over-the-counter medicines, dietary supplements, and herbal remedies. This can help avoid dangerous drug interactions between ondansetron and another OTC product or prescription medication.
• You can take ondansetron with or without food.
• If you are taking the disintegrating tablet of Zofran, remove the foil backing with dry hands and immediately place the tablet under your tongue.
• Besides common side effects of ondansetron, like headache, tiredness, diarrhea, and constipation, this medicine can also cause dizziness. Do not drive or operate machinery until you know how ondansetron affects you. Drinking alcohol can make these side effects worse.
• In case of a missed dose, take your Zofran dose as soon as you remember. If it is time for the next dose, however, skip the missed dose and take the next dose according to the prescribed schedule. Do not take two doses to make up for a missed dose.

References:

1. https://medlineplus.gov/druginfo/meds/a601209.html
2. https://www.accessdata.fda.gov/drugsatfda_docs/label/2016/020103s035_020605s019_020781s019lbl.pdf
3. https://journals.lww.com/ajnonline/Abstract/2012/10000/The_FDA_Limits_Maximum_IV_Dose_of_Ondansetron.27.aspx

Nausea and vomiting during chemotherapy

Practice shows that most patients who learn about the need for chemotherapy, most often fear the development of painful nausea and vomiting. Oddly enough, many non-oncologists are convinced that cytostatic treatment is impossible without the development of these side effects. It is worth recognizing that such an opinion has some “historical” roots. In 1983, during a survey of cancer patients, it was nausea and vomiting that patients noted as the first and second most important side effect of chemotherapy. Despite the fact that these complications do not pose an immediate threat to life, they are subjectively extremely difficult to tolerate by patients. In addition to a decrease in the quality of life, nausea and vomiting can also lead to quite objective problems: the inability to take pills, dehydration, stomach bleeding, etc. In some cases, nausea and vomiting may even cause the patient to refuse to continue treatment. This was the reason for conducting a large number of studies on antiemetic therapy, the development and implementation of new effective antiemetic drugs and regimens for their use. Thanks to scientific research, by 2002, the optimization of antiemetic therapy made it possible to exclude nausea and vomiting from the dozens of problems most significant from the point of view of a patient receiving cytostatic therapy. It should be noted that such progress was achieved due to the observance of the developed standards of antiemetic therapy.

We would like to acquaint patients and general practitioners with these standards and, if possible, dispel a number of existing myths that often interfere with adequate chemotherapy. Depending on the timing and mechanisms of development, there are three main types of nausea and vomiting that can develop in cancer patients during chemotherapy – acute, delayed and previous.

Acute nausea and vomiting develop in the first 24 hours after the administration of cytostatics. This type of vomiting is highly intense, but is well controlled by modern antiemetic therapy, as will be discussed later.

The second type is delayed nausea and vomiting. It occurs 24 hours or more after the introduction of cytostatics, it can last several days, at the same time it is less intense compared to acute. It is believed that acute and delayed nausea and vomiting are caused by the action of biologically active tissue decay products on specific “emetic” receptors in the peripheral and central nervous system.

The problem of so-called antecedent nausea and vomiting stands apart. This type of vomiting is situationally determined (symptoms can appear both in the clinic and outside it, when talking about chemotherapy or when the patient feels specific smells, tastes) and develops according to the mechanism of a “conditioned” reflex and is more often observed in patients who have previously received inadequate prophylaxis acute and delayed vomiting.

The greatest success has been achieved in the prevention and treatment of acute nausea and vomiting, which is due to the identification of the main biologically active substance responsible for its development – serotonin. The discovery of drugs that specifically block serotonin receptors has revolutionized antiemetic therapy. A striking example of the effectiveness of serotonin receptor antagonists is their use during chemotherapy using the most emetogenic (i.e., vomiting-inducing) drug – Cisplatin. Before the introduction of serotonin antagonists, more than 99% of patients receiving such chemotherapy experienced nausea and vomiting, often multiple and multi-day. Currently, about 80% of patients receiving similar therapy do not suffer from nausea and vomiting at all (complete control), while in the rest these side effects are much less pronounced.

The following antiemetics of the first generation, belonging to the group of serotonin receptor antagonists, are currently represented on the Russian pharmaceutical market: Kitril, Navoban, Zofran. Despite the fact that these drugs differ somewhat in chemical structure, degree of binding to serotonin receptors and half-life from the body (Zofran 4 hours, Navoban 7.3 hours, Kytril 8.9hours), they are equally effective when used in adequate doses. Due to the fact that the effect of the drug develops when all specific receptors are saturated (blocked), lower doses are not effective, and increasing doses above the recommended ones does not increase the effect, but only makes the therapy more expensive.

The recommended doses of these drugs are: Zofran 8 mg IV or 24 mg orally; Navoban – 5 mg IV or 5 mg orally; Kytril 1 mg IV or 2 mg orally (MASCC 2002). The above drugs from the group of serotonin receptor antagonists are practically devoid of significant side effects. And although their administration may be accompanied by headache, constipation, dyspepsia, these side effects are usually mild.

Along with Zofran, Navoban and Kitril, introduced to the market by the development company, there are a large number of their analogues based on the same active substance, but produced by other companies. The active substance of the drug Zofran – Ondansetron contains the drugs Emeset, Latran, Emetron, etc., Navoban – Tropiserton, the drug Tropindol. There are currently no analogues of Kitril (Granisetron) on the Russian market. According to international clinical trials, the listed drugs must be used without fail during high and medium emetogenic chemotherapy. The emetogenicity (literally – nausea) of therapy is determined by the cytostatics included in the treatment regimen. Below is the distribution of the most commonly used chemotherapy drugs according to the degree of their emetogenicity. The degree of emetogenicity of chemotherapy drugs

In addition to serotonin, several other biologically active substances are also responsible for the development of nausea and vomiting, which, for example, is confirmed by the lower effectiveness of serotonin receptor antagonists for the prevention of delayed emesis. The use of drugs in combination with antagonists of serotonin receptors that act on alternative pathways for the activation of the vomiting center can increase the number of patients who do not experience nausea and vomiting after chemotherapy. The most important of the “complementary” antiemetics is Dexamethasone. Studies have shown that the addition of this cheap but highly effective drug to serotonin receptor antagonists can further reduce the possibility of acute nausea and vomiting by 20-30%. In the period after chemotherapy, this drug is most effective in preventing the development of delayed nausea and vomiting. Dexamethasone is the drug of choice for the prevention of delayed nausea and vomiting. In addition, it has independent antiemetic activity and can be used as monotherapy for the prevention of acute vomiting after the administration of low-emetogenic cytostatics. It is important to remember that Dexamethasone should always be used in cases of chemotherapy requiring the appointment of serotonin receptor antagonists.

Another antiemetic drug, Cerucal (Metoclopramide), which was previously widely used in high doses for the prevention of acute nausea and vomiting after high-medium emetogenic chemotherapy, is currently practically not used for this purpose, because with comparable efficacy with serotonin receptor antagonists, it has a significant number of pronounced side effects. According to international recommendations, the use of Cerucal is only permissible in standard doses for the prevention of acute nausea and vomiting after low-emetogenic chemotherapy and for the prevention of delayed vomiting in combination with Dexamethasone.

Based on the analysis of the results of numerous studies, the International Association for Supportive Care in Oncology (MASCC) has developed the following principles for antiemetic therapy:

1. Adequate antiemetic therapy should begin already with the first course of chemotherapy. It is unacceptable to leave more effective drugs “for later”, because. this increases the risk of nausea and vomiting in subsequent courses of chemotherapy, even in the case of the use of the most effective antiemetics.
2. On the first day of treatment, a combination of effective doses of serotonin receptor antagonists and Dexamethasone must be used during high and medium emetogenic chemotherapy.
3. In high- and moderately emetogenic chemotherapy, prevention of delayed nausea and vomiting by prescribing a combination of Dexamethasone with Cerucal at standard doses or with serotonin receptor antagonists should be mandatory. Prevention should be carried out for as long as patients remain at risk of developing these complications (3 days after the end of chemotherapy).
4. For the prevention of nausea and vomiting after low-emetogenic chemotherapy, the use of Dexamethasone or Cerucal in a standard dose is sufficient.
5. There is no convincing evidence of the advantage of prescribing antiemetic drugs several times a day over a single injection (immediately before the administration of chemotherapy drugs).
6. There is no convincing evidence of the advantage of intravenous administration of antiemetics over oral administration (in the form of tablets or capsules).

Compliance with the above rules allows you to minimize the risk of developing acute and delayed nausea and vomiting, which in turn reduces the risk of developing previous vomiting.

If, despite antiemetogenic therapy, the patient still experiences nausea and vomiting, the most common reason for this is non-compliance with the recommendations (inadequate dose of serotonin receptor antagonists, lack of Dexamethasone in the antiemetic regimen, etc.). Usually, this situation is quite easily resolved and requires only bringing antiemetic therapy to generally accepted standards. If the patient is already receiving adequate therapy, but the desired effect is not achieved, the following approaches may be used: the introduction of an additional dose of serotonin receptor antagonists, the use of another drug from this group in subsequent cycles of chemotherapy (for example, the use of Kitril after failure of therapy with Zofran or Navoban, etc. .), the use of sedatives.

The results of recently completed clinical trials of palonosetron, a second-generation serotonin receptor antagonist, give hope for a more effective antiemetic therapy in this group of patients.

However, one should not forget about other possible causes of nausea and vomiting during chemotherapy that are not directly related to it. These can be erosive and ulcerative processes in the gastrointestinal tract, inadequate correction of arterial hypertension, various disturbances in water and electrolyte balance, etc.

Due to the fact that the information given in our article is often the property of only oncologists, a number of misconceptions (myths) about nausea and vomiting continue to exist among patients and doctors of other specialties, which frighten patients and prevent normal antitumor therapy.

Let’s consider these myths in more detail.

Myth 1. Chemotherapy is necessarily accompanied by severe multi-day nausea and vomiting.

Even with high and medium emetogenic chemotherapy (without adequate antiemetic therapy, which causes nausea and vomiting in 60-100% of cases), compliance with modern standards of antiemetic therapy avoids the development or reduces the intensity and duration of nausea and vomiting in the vast majority of patients. Nausea and vomiting are currently excluded from the ten most significant side effects of chemotherapy from the point of view of patients in clinics that adhere to antiemetic therapy standards.

Myth 2. The development of nausea and vomiting indicates the effectiveness of ongoing antitumor treatment (“nausea means effective”).

Nausea and vomiting are side (undesirable) effects of ongoing chemotherapy and are in no way related to the main (antineoplastic) effect of the treatment. Modern effective antiemetic drugs do not reduce the antitumor effect, i.e. protect the patient from the undesirable effects of chemotherapy, “without interfering” with its effect on the tumor. Therefore, the absence of nausea and vomiting should be a reason for joy, not grief.

Myth 3. The higher the dose of antiemetics, the more effective they are.

Increasing the dose of an antiemetic above the recommended dose does not increase the effectiveness, only makes it more expensive.

Myth 4: Intravenous administration of antiemetics is much more effective than oral administration.

Current evidence suggests that the efficacy of antiemetics at recommended doses does not differ by route of administration.

Myth 5. Older people are more likely to develop nausea and vomiting.

At the very least, older age is not an increased risk factor for nausea and vomiting, and several studies have shown that older patients are less likely to experience nausea and vomiting than younger patients.

Thus, the arsenal of effective antiemetic drugs currently in the hands of oncologists makes it possible to successfully cope with nausea and vomiting after chemotherapy.

We hope that our article will help patients who are recommended chemotherapy, not become victims of prejudice and more courageously agree to the proposed anticancer treatment.

— c.m.s. Zhukova L.G. ( based on Together against Cancer)

HELP FOR CANCER PATIENTS WITH NAUSE AND VOMITING

Nausea 9 0088 – an extremely unpleasant sensation of impending vomiting, often accompanied by pale skin, sweating, increased salivation.

Vomiting – eruption of stomach contents. Usually nausea and vomiting accompany each other, have one reflex mechanism.

These states are not only unpleasant, they are dangerous. When vomiting, a large amount of fluid and electrolytes is lost, which disrupts the activity of absolutely all body systems and, first of all, the cardiovascular system. With dehydration, the likelihood of thrombosis increases sharply, because in cancer patients with an unremoved tumor or metastases, the mechanism of blood clotting is significantly impaired. And finally, during vomiting, the mucous membrane of the upper gastrointestinal tract is damaged.

In cancer patients, causes of nausea and vomiting may include:

• chemotherapy and anticipation of chemotherapy;
• radiation therapy;
• complications of a tumor of the gastrointestinal tract: consequences of gastric resection; inoperable tumor;
• brain tumor or metastases;
• liver metastases;
• renal insufficiency ( uremia ) in case of kidney cancer, removal of the kidney, or damage to the kidneys by anticancer drugs;
• tumor intoxication in the terminal stage of the disease;
• inflammatory and infectious diseases.

Nausea and vomiting occur when specific receptors are irritated in the gastrointestinal tract, in the vestibular apparatus of the ear, or when the vomiting center located in the brain is directly irritated. The vomiting center not only receives information from the periphery, but also “manages” the vomiting act, coordinating the actions of the muscles. The threshold of irritation of the center is individual, and in men it is higher than in women.

Nausea and vomiting are treated according to the underlying cause. There is no universal drug that would relieve severe symptoms with a trigger of various kinds.

The most common cause of nausea and vomiting in cancer patients is cancer medication. It is impossible to predict the response to chemotherapy in any given patient. With repeated, absolutely similar courses of chemotherapy, nausea will differ in the time of occurrence, and in quality, and in duration. It will be influenced not only by the psychological and physical state, but also by the time of year and the weather, and the food eaten the day before.

There are more than 20 drugs of seven groups that help in the fight for the quality of life during chemotherapy: some act on the peripheral, others on the central systems. As a rule, nausea directly during chemotherapy and in the next day after it is due to irritation of the vomiting center. Later, cell breakdown products and drug metabolites irritate receptors in the gastrointestinal tract. Therefore, drugs of different directions should be used at different times: central or peripheral action.

For the relief of nausea and vomiting caused by chemotherapeutic agents, 5HT-3 receptor antagonists are necessarily used, in Russia three drugs and their generics are used: ondansetron ( zofran, latran, emiset ), granisetron ( kitril ) and tropisetron ( navoban, tropindol ). Introduced or taken within 30 min. – 1 hour. before cytostatic, they have a good preventive effect. Their effectiveness (in equivalent doses) is approximately the same, but the time of therapeutic activity is different: granisetron and tropisetron act longer than ondansetron. Increasing the dose does not affect the effectiveness of granisetron and tropisetron, unlike ondansetron, the dose of which is 4-32 mg.

Various formulations are available: solutions, tablets, rectal suppositories, syrups. We should not forget that primary resistance to any drug is possible: it helps someone, but not someone. If you think that the drug did not help at all, in the next course, replace it with an analogue from the same group.

On the next day after the administration of the chemotherapy drug, it is advisable to use not only the already mentioned 5HT-3 receptor antagonists, but also drugs of peripheral action: metoclopramide ( cerucal raglan ), dimetpramide or motilium.

Patients often experience nausea while waiting for or remembering chemotherapy, and on the way to the treatment room they cannot resist the urge to vomit. This so-called “pre-nausea and vomiting” or psychogenic reaction is a prime example of an anxiety state. In order to avoid it, it is necessary to use sedatives on the eve of chemotherapy: these are “strictly accountable” drugs, and they are issued only by prescription.

Nausea and vomiting associated with radiotherapy is a concern for a small number of patients and is much less severe than with chemotherapy. Metoclopramide (cerucal raglan), dimetpramide, or motilium usually help. Centrally acting drugs ( 5HT-3 receptor antagonists ) are ineffective. A special case: radiation therapy of the brain for tumors or metastases, when radiation edema of brain tissues joins nausea and vomiting caused by increased intracranial pressure. In such a situation, antiemetics are useless, and a set of measures is needed to reduce swelling of the brain.

Everyone knows that diseases of the gastrointestinal tract, starting with banal gastritis and colitis, are complicated by vomiting. Tumors are no exception, but more often in this case, regurgitation, or the expulsion of food masses, without concomitant nausea and diaphragmatic contraction, still occurs in response to cavity stretching. After resection of a part of the stomach, Dumping syndrome may develop, caused by the rapid intake of insufficiently processed food by gastric juice into the jejunum; the syndrome is manifested by severe weakness to fainting, palpitations, nausea and vomiting. In this situation, a special dietary regimen helps.

Brain tumors cause increased intracranial pressure, which is manifested by nausea and vomiting, blurred vision (double vision, changes in visual fields), headaches and neurological disorders. The condition is facilitated by high doses of hormones and diuretics, antiemetics are powerless.

Liver metastases of malignant tumors often present with nausea and vomiting, mild fever, severe weakness and, in advanced form, jaundice and ascites ( abdominal effusion ). Relief is provided by moderate and high doses of hormones ( glucocorticoids ) and peripherally acting antiemetics.

In renal insufficiency due to a decrease in kidney function, which leads to the removal of the kidney or damage to the kidney by a tumor or cytostatics, as well as tumor intoxication, the concentration of waste products in the blood increases. The intensity of symptoms depends on the concentration of toxic substances, which can be reduced by intravenous detoxification therapy.