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Avatar universal

innoculations before trip to India, while also on tamoxifen

I am currently taking tamoxifen and am about to get various innoculations for a trip to Chennai in south India (tropical climate).  These will include anti-malaria drugs, hepatitis vaccines (A, B & C, I believe), polio and MMR vaccines,and I don't know what else yet. I heard that certain anti-malaria drugs (including  chloroquine, pyrimethamine and quinine) interact with tamoxifen.

I have several questions: How do these drugs interact with tamoxifen? By causing physical symptoms, by reducing or blocking tamoxifen's effectiveness?  Do the hepatitis or polio or MMR vaccinations interact with tamoxifen?  If so, how?  Thanks.
6 Responses
616411 tn?1221767853
Vaccine-Preventable Diseases
Vaccine recommendations are based on the best available risk information. Please note that the level of risk for vaccine-preventable diseases can change at any time.

Vaccination or Disease Recommendations or Requirements for Vaccine-Preventable Diseases
Routine  Recommended if you are not up-to-date with routine shots such as, measles/mumps/rubella (MMR) vaccine, diphtheria/pertussis/tetanus (DPT) vaccine, poliovirus vaccine, etc.

Hepatitis A or immune globulin (IG) Recommended for all unvaccinated people traveling to or working in countries with an intermediate or high level of hepatitis A virus infection (see map) where exposure might occur through food or water. Cases of travel-related hepatitis A can also occur in travelers to developing countries with "standard" tourist itineraries, accommodations, and food consumption behaviors.

Hepatitis B  Recommended for all unvaccinated persons traveling to or working in countries with intermediate to high levels of endemic HBV transmission (see map), especially those who might be exposed to blood or body fluids, have sexual contact with the local population, or be exposed through medical treatment (e.g., for an accident).

Typhoid  Recommended for all unvaccinated people traveling to or working in South Asia, especially if visiting smaller cities, villages, or rural areas and staying with friends or relatives where exposure might occur through food or water.
Rabies  Recommended for travelers spending a lot of time outdoors, especially in rural areas, involved in activities such as bicycling, camping, or hiking. Also recommended for travelers with significant occupational risks (such as veterinarians) for long-term travelers and expatriates living in areas with a significant risk of exposure, and for travelers involved in any activities that might bring them into direct contact with bats. Children are considered at higher risk because they tend to play with animals, may receive more severe bites, or may not report bites. Note: Rabies vaccine is temporarily in limited supply. For updates on the rabies vaccine supply, please check the Rabies News and Highlights page regularly.
Japanese encephalitis  Recommended if you plan to visit rural farming areas and under special circumstances, such as a known outbreak of Japanese encephalitis, see country-specific information.
Polio  Recommended for adult travelers who have received a primary series with either inactivated poliovirus vaccine (IPV) or oral polio vaccine (OPV). They should receive another dose of IPV before departure. For adults, available data do not indicate the need for more than a single lifetime booster dose with IPV.

616411 tn?1221767853
Drugs to Prevent Malaria (antimalarial drugs)
If you will be visiting a malaria risk area in India, you will need to take one of the following antimalarial drugs: atovaquone/proguanil, doxycycline, or mefloquine (primaquine in special circumstances and only after G6PD testing).

Note: Chloroquine is NOT an effective antimalarial drug in India and should not be taken to prevent malaria in this region.

Malaria risk area in India: Risk in all areas throughout country except no risk in areas above 2,000 m (>6,561 ft) in Himachal Pradesh, Jammu, Kashmir, and Sikkim. Risk also exists in urban areas below 2000 m, including Delhi and Mumbai (Bombay).
If you have visited a malaria-risk area, continue taking your antimalarial drug for 4 weeks (doxycycline or mefloquine) or seven days (atovaquone/proguanil) after leaving the risk area.

With regards to these medications interacting with your Tamoxifen, I can only tell you that there isn't a reaction listed between Tamoxifen and Mefloquin ( for anti- malaria). I would suggest you contact your oncologist with this list and ask him or her to discuss this with you.

Best of luck to you and safe travels!

Jennifer R RPh www.drugstore.com

Avatar universal
Thank you for the information , it's good to have.  But what I really want to know is how do all these innoculations affect tamoxifen.  I read that anti-malaria drugs "interact" with tamoxifen, but the information I read did not say how these drugs interact.  

I don't want to take anything that will block or reduce the effectiveness of the tamoxifen I am taking.  I would rather cancel the trip to India.  

How do anti-malaria drugs and the other vaccines --typhoid fever, hepatitis A,B & C, even polio and MMR-- affect tamoxifen?  Will any of these drugs reduce the effectiveness of tamoxifen, or even produce a toxic interaction with it?  Thank you.  
Avatar universal
Thank you.
616411 tn?1221767853
For that I would have to refer you to your oncologist. Here is a bit more information that you can bring to him or her to make your decision.

Atovaquone/proguanil (brand name: Malarone ™)
Atovaquone/proguanil is a combination of two drugs, atovaquone plus proguanil, in one tablet. It is available in the United States as the brand name, Malarone.

Directions for Use

The adult dosage is 1 adult tablet (250 atovaquone/100 mg proguanil) once a day.
Take the first dose of atovaquone/proguanil 1 to 2 days before travel to the malaria-risk area.
Take your dose once a day during travel in the malaria-risk area.
Take your dose once a day for 7 days after leaving the malaria-risk area.
Take your dose at the same time each day and take the pill with food or milk.
Side Effects and Warnings

The most common side effects reported by travelers taking atovaquone/proguanil are stomach pain, nausea, vomiting, and headache. Most people taking this drug do not have side effects serious enough to stop taking it; if you cannot tolerate atovaquone/proguanil, see your health care provider for a different antimalarial drug.

Travelers Who Should Not Take Atovaquone/Proguanil for Prophylaxis

The following travelers should not take atovaquone/proguanil to prevent malaria and should take a different antimalarial drug (see your health care provider):

children weighing less than 11 pounds (5 kilograms) (Updated December 22, 2006)
pregnant women
women breast-feeding infants weighing less than 11 pounds (5 kilograms) (Updated December 22, 2006)  
patients with severe renal impairment
patients allergic to atovaquone or proguanil.

Mefloquine (brand name Lariam ™ and generic)
Directions for Use

The adult dosage is 250 mg (one tablet) once a week.
Take the first dose 1 week before arrival in the malaria-risk area.
Take your dose once a week, on the same day of the week, while in the risk area.
Take your dose once a week for 4 weeks after leaving the risk area.
Take the drug on a full stomach with a full glass of liquid.
Side Effects and Warnings

The most common side effects reported by travelers taking mefloquine include headache, nausea, dizziness, difficulty sleeping, anxiety, vivid dreams, and visual disturbances. Mefloquine has rarely been reported to cause serious side effects, such as seizures, depression, and psychosis. These serious side effects are more frequent with the higher doses used to treat malaria; fewer occurred at the weekly doses used to prevent malaria.

Mefloquine is eliminated slowly by the body and thus may stay in the body for a while even after the drug is discontinued. Therefore, side effects caused by mefloquine may persist weeks to months after the drug has been stopped.

Most travelers taking mefloquine do not have side effects serious enough to stop taking the drug. (Other antimalarial drugs are available if you cannot tolerate mefloquine; see your health care provider.)

Travelers Who Should Not Take Mefloquine

The following travelers should not take mefloquine and should ask their health care provider for a different antimalarial drug:

persons with active depression or a recent history of depression
persons with a history of psychosis, generalized anxiety disorder, schizophrenia, or other major psychiatric disorder
persons with a history of seizures (does not include the type of seizure caused by high fever in childhood)
persons allergic to mefloquine
Mefloquine is not recommended for persons with cardiac conduction abnormalities (for example, an irregular heartbeat).

( Those are the 2 main drugs prescribed for Malaria prophylaxis. )
Best of luck to you.
Jennifer R RPh www.drugstore.com
Avatar universal
Thanks again.
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