Use caution with these juices

While vegetable and fruit juices are generally very healthy to consume, there are some types of juice that can be harmful under certain conditions or can interact negatively with some medications. Here are the three that demand a higher level of caution.

Dangerous juices
Dangerous juices

Grapefruit juice: Strong interactions with many medications

Grapefruit juice affects more than half of all medications. With some medications, you cannot ever drink grapefruit jucie. With others, you can drink limited amounts if spaced several hours after taking the medication. Make sure to read the interactions information of any medicine carefully. What often happens is that active compounds of grapefruit juice reduce the efficiency of digestive enzymes. This leads to much higher amounts of medication being absorbed into the body, leading to a possible overdose.

  • Grapefruit juice strongly interacts with many high blood presure medications including felodipin, nifedipin, and eplerenon. It can lead to greatly reduced blood pressure and can be life threatening, especially in people with weak hearts or harening of the arteries. But it isn't true for all high blood pressure drugs. For example, grapefruit juice reduces the effects of losartan.
  • Be especially careful with statin drugs used to treat high cholesterol. Grapefruit juice interacts strongly with simvastatin, lovastatin and atorvastatin. According to studies, one glass of juice increases these drug's potency by up to 250%. Other statins, such as rosuvastatin, fluvastatin (Lescol) and pravastatin are safe to take with grapefruit juice. 

grepová šťáva - interakce

In addition, be sure to check for contraindications when taking medication for the following conditions:

  • heart rhythm disorders (including amiodaron, chinidin, dronedaron)
  • allergies (some corticosteroids and antihistamines, such as fexofenadin)
  • pain (including fentanyl, oxycodon, kolchicin)
  • anxiety and depression (benzodiazepamines, sertralin, buspiron a more)
  • asthma and COPD
  • blood clotting asthma and COPD (blood thinners with certain active substances, eg apixaban, rivaroxaban, clopidogrel, ticagrelor)
  • enlarged prostate (including tamsulosin)
  • cancer
  • epilepsy (Carbamazepine)
  • erectile disfunction (Viagra)
  • HIV / AIDS
  • thyroid disorders (levothyroxin)
  • viral, bacterial, and fungal infections (antivirals, antifungals, antibiotics)
  • cough (dextrometorfan)
  • contraceptives (hormonal contraceptives; it's usually recommended to wait at least 5 hours after taking the pill before consuming grapefruit juice)

The list is not complete but at the same time it doesn't mean that you must completely exclude grapefruit juice. The severity of side effects increases with age and with higher doses of medication. It also depends on the enzyme levels in the intestines and the amount of juice drunk. If you do not want to give up grapefruit juice for good, talk to your doctor. Depending on the situation, you may be allowed a limited amount. Or a doctor can recommend a time interval between taking the medicine and drinking the juice, or prescribe a reduced dose the day you drink the juice. However, with some medications grapefruit consumption is completely not allowed. 

The effect of drugs is also influenced by other citruses, albeit less intensely. For example, lemon juice increases the effect of high blood pressure medication by 25%, orange juice by 32%.

zázvorová šťáva - interakce
zázvorová šťáva - interakce

Ginger juice

Ginger acts a a blood thinner, lowers blood pressure, and can reduce the effectiveness of some medicines. Smaller quantities of ginger juice are safe, but larger amounts comsumed regularly should be taken withcaution. If you have any of the following conditions, please consult a doctor before drinking ginger juice:

  • You are pregnant, especially in the 3rd trimester. Ginger can cause miscarriage or premature birth.
  • You have haemophilia or problems with blood not clotting.
  • You have cardiovascular disease.
  • You have diabetes (ginger can cause hypoglycemia).
  • You are taking anti-clotting medicines (heparin, warfarin), insulin or other blood glucose lowering medicines, non-steroidal anti-inflammatory medicines (aspirin, ibuprofen, naproxen, diclofenac), high blood pressure medicines, beta-blockers or tacrolimus.
  • You have an underweight or have an eating disorder (ginger speeds up metabolism and suppresses appetite).
  • You are two weeks before or two weeks after surgery.
  • You have an upset stomach, stomach ulcers or gallstones.
  • You are an adolescent girl and expect or just began menstruation (ginger intensifies menstrual bleeding, especially at a younger age).
  • You are less than 2 years old :)
celerová šťáva - interakce
celerová šťáva - interakce

Celery juice

Celery is a known allergen and can affect the potency of some drugs. In most cases, celery juice is safe, but caution or medical advice is recommended if:

  • You have an allergy to celery (it is often common with pollen allergies).
  • You are pregnant or trying to conceive.
  • You have acute gout.
  • You are currently taking paracetamol (celery juice prolongs the effect).
  • You are taking a sedative, that is, drugs that depress the central nervous system including hypnotics (for sleeping), anxiolytics and benzodiazepamines (for anxiety disorders).
  • You are taking levothyroxine, a medicine for thyroid conditions.
  • You are taking lithium for bipolar disorder.
  • You are taking medicines or herbs that increase sensitivity to sunlight (i.e. antibiotics, antihistamines, psychopharmaceuticals, hormonal contraceptives, St. John's wort).

If you are interested in juicing celery, see our article for recommendations of the best juicer types for celery.

Published: 11. October 2019