Some herbs can influence the effect of medication, making it less effective or more effective. To make people aware that medicines and herbal remedies do not always go well together, the Medicines Evaluation Board (CBG) and the Dutch Food and Consumer Product Safety Authority (NVWA) are starting the campaignKnow what you are taking.
Interaction
Many drug users also use herbal supplements in addition to their medication, without the supervision of a healthcare provider, with the idea “if it doesn’t help, then it won’t hurt”, says the MEB. This can hinder the safe use of medicines. Herbal supplements can change the effect of medications. A medicine can then work less well or more strongly. Or someone may experience more side effects. Sometimes a combination can have serious consequences, such as increasing drowsiness or palpitations.
11 commonly used herbs
The “Know what you’re taking” campaign focuses on 11 commonly used herbs, which are known to influence the effect of medication. This does not concern herbs as they are used in the kitchen for cooking, such as a clove of garlic or a teaspoon of turmeric, but plant extracts that are processed in high concentrations in capsules or drinks. This concerns the following herbs:
- American ginseng
- cannabis
- red sage
- turmeric
- Ginkgo biloba
- valerian
- garlic
- Milk thistle
- St. John’s wort
- green tea
- echinacea
The medications these herbs can interact with are diverse and range from antacids, antidepressants, and sleep aids to anticoagulants.
Beneficial addition
Sometimes it is beneficial to use supplements in addition to medication. Certain medications can reduce the absorption of nutrients, which increases the risk of vitamin or mineral deficiency. For example, the use of metformin increases the risk of a vitamin B12 deficiency. A vitamin B12 supplement can then offer a solution. And long-term use of the contraceptive pill increases the risk of folic acid and magnesium deficiency. The IVG information page about the simultaneous use of medicines and supplements provides a clear overview of which (herbal) supplements are useful and which do not go well together.
View of use
According to the MEB and NVWA, those who do not use medication do not have to worry about interactions. Consumers who have doubts about side effects or reduced effectiveness are advised to consult an expert. It is important that doctors, pharmacists and dieticians ask patients about the use of herbal supplements.
Source: NVWA
