How do I know which herbs not to take at the same time? For example, I was taking a tincture for PMS symptoms when I felt a cold coming. So I also started taking a tincture to build immunity. After a couple days of taking both, I started getting a rash on my arms. I had taken both of these tinctures in the past with no reaction but never at the same time. I stopped taking both and the rash cleared. I don’t double up on tinctures any more, even though there are times I need to, but I do drink herbs in my tea while taking tinctures – not sure if that will cause problems. Other than trial and error, is there a way to know what shouldn’t be taken at the same time? I only let my kids take one thing at a time (no tea when taking a tincture) because I don’t know if they will have a reaction worse than a rash. (I also am not comfortable making my own herbal blends, not knowing if certain herbs together may cause a reaction.)
First let me say thank you for participating in my first Ask the Herbalist post! I pray what I offer helps you use herbs more confidently, comfortably, and safely. From what I understand your main question is “How do I know which herbs not to take at the same time?”
I would like to briefly discuss the rest of your comments before delving into the specifics of your question. Because I am not aware of the specific herbs you were taking, and if they were simples or combinations, it is difficult for me to address your comments specifically. That said I will say that because both tinctures were ones you have taken previously the rash you described would not be what I would expect to see as an interaction. A rash is also not a common side effect of herbal medication unless it is an allergic reaction. This would lead me to wonder if there had not been another cause of your rash. As I said I am not aware of what tinctures you were taking and so I am offering my input while considering my limited knowledge of the specific situation.
The Question of Combining Herbal Remedies Safely
While it is important to make sure that there are no Medication/Herb interactions, generally herbs do not have a lot of strong interactions with each other. Therefore there are not major concerns with taking them at the same time. Taking tinctures concurrently with mild teas, infusions, and decoctions is fairly normal in the herbal world. There are some considerations such as not taking demulcent digestive herbs like slippery elm, or marshmallow at the same time as other non digestive herbs. This can be easily remedied by taking them at least an hour apart. Another consideration would be not taking herbs that counteract the desired effect such as strong stimulating herbs with a calming herb for sleep or anxiety. I do want to be clear while it is not common it is still possible for herbs to interact with each other.
The specific question you are asking would fall under what would be called Therapeutic incompatibility.
David Hoffmann defines this in his book Medical Herbalism as:
A therapeutic incompatibility is defined as an undesirable pharmacological interaction between two or more ingredients that may potentiate the therapeutic effects of the ingredients, reduce the effectiveness of one or more of the ingredients, or cause toxicity in the patient.
A simple way to avoid this incompatibility is to choose simples instead of formulas. A simple is a single herb used for its therapeutic or tonic effects. The benefit of using simples is that if you have a reaction you will easily know what is causing it. It can also help you to get to know each herb really well. If you do decide to make formulas then you can use the herbs that you have already tested individually. Some herbalists feel that these single remedies do not provide the therapeutic benefit that formulas can and have the potential for greater side effects, while other herbalists feel the more herbs in a formula the greater potential for side effects. While I love using individual remedies I do not limit myself to them, I do personally prefer to keep my formulas uncomplicated. I actually do not encourage the use of a lot of pre-made formulas, capsules or remedies that have large lists of herbs. I feel formulas with 6-9 herbs are best used only if made for the specific individual and situation.
Formulation of herbal remedies can be basic or detailed. It is best to stick to basic formulation unless you have taken more advanced course. The interesting thing is that herbs that increase or reduce therapeutic effects are often used together in formulas because of this action. You can combine two herbs together to get a stronger therapeutic effect or to reduce some of the stronger therapeutic effects, or potential side effects. This is where herb combining can shine to create beautiful healing remedies. There are some herbal constituents you do specifically want to avoid combining in tincture form. Tannin rich herbs should not be mixed with alkaloid containing herbs because they can bind together and form insoluble compounds in your tincture.
When formulating herbs it is always important to consider the individual needs of the person and the issue at hand. Other considerations are medications, diagnosis, individual constitutions, herbal actions, and properties, as well as flavor. There are many different system of herbal formulation and the details of creating formulas is beyond the scope of this article. You can keep your formulas simple by using only three herbs until you become more advanced at formulating. Avoid using toxic herbs or herbs that are extremely strong. Using herbs that are tonic, nutrient, or normalizing can help reduce the possibility of side effects. A few examples are Raspberry leaf, Oats and Nettles. Choose herbs specific to the body system being considered, or the complaint, and include an herb to assist with flavor, balance, reduce possible symptoms, or increase bioavailability.
To sum things up generally you should not have a problem using two remedies at the same time as long as you keep in mind the few issues mentioned, and make sure that the herbs themselves are the correct herb for the situation, and are used in safe dosages.
Bad Formulating Combinations by Michael Moore
Simples and Formulas by Kiva Rose
Formulating by Heron Botanicals
Medical Herbalism-David Hoffman chapters 11 and 12
This information is not meant to diagnose, treat, or prescribe you or a disease. Nor is it a replacement for care from a licensed medical practitioner but is for educational purposes only.