MEDICINAL PLANTS - GET TO KNOW THEM

Each day more and more people become acquainted with medicinal plants. Who has not taken a chamomile tea after a hearty meal? Who has not used some linden tea to calm their nerves before bed? Beyond these popular remedies, there is room in your home medicine cabinet for others that have been proven effective to relieve everyday problems and that offer more advantages than synthetic products. Looking at the entire repertoire that nature offers us, it is easy to find plants that have great healing properties and can be very useful to treat many ailments. In fact, of the 50,000 to 70,000 varieties of plants that are estimated to have ever been used for therapeutic purposes, we offer a selection of the most well-known plants that are easy to find in health food stores and pharmacies. Rosemary, thyme, bay, anise, dandelion … these are varieties that you have seen more than once in their natural state, and now you will know how to use them at home and discover how they can help against all kinds of disorders.

However, keep in mind that self-medication with herbal remedies is also dangerous; therefore, you must pay attention to the dosage and potential risks.

The fact that we can claim that certain plants are “medicinal” means that they possess a number of biologically active substances, active ingredients, which give them the ability to act on certain ailments. Although there are still many components waiting to be discovered, some of them have been identified and isolated, and research has allowed us to better understand their effects on the body. In most cases, the medicinal effect of a given plant depends on not just one but various active ingredients acting synergistically together. Generally, one plant has different properties that are useful in different situations, and it is more efficient to use the plant than to use just one of its active ingredients separately.

Keep in mind that the content of these substances can vary within a species, depending on factors such as irrigation, soil, harvesting time, and so forth. We have grouped the plants into several categories according to their chemical nature.


• Carbohydrates

Also known as saccharide, they are abundant and there are several types. The most significant are:

Sugars: simple carbohydrates (such as glucose and fructose). They have a toning effect and are abundant in fruits.

Mucilage: solution with a gelatinous consistency, often found on the outer integument of seeds, as well as in other organs of the plant. They hold water, swell, and increase in volume, so some plants that are rich in mucilage act as laxatives, to relieve coughing, and to treat skin disorders. Greater plantains, mallow, linden flower, and aloe are rich in mucilage.

Inulin: this complex carbohydrate promotes digestion and is well tolerated by diabetics. Chicory and dandelion are rich in inulin.

• Lipids

The most important group of plant-derived fatty substances are oils.

Oils: are obtained by cold pressing the seeds and fruits of several plant species. They usually consist of unsaturated fatty acids and are liquid. They have laxative, lipid lowering (cholesterol lowering), and emollient properties. Evening primrose oil, olive oil, and borage oil are the most common.

• Amino acids

Although you can find them in free form, you most often see them as part of more complex structures. The most important are:

Enzymes: although plants have many enzymatic compounds, only some of them such as proteolytic enzymes are used in phytotherapy. A plant that stands out for its content of such enzymes is the papaya.

Sulfur compounds: some plants have a series of active sulfur compounds that are biosynthesized from amino acids. One of the most common is garlic.

• Phenolic compounds

Simple phenols: this group includes compounds that are less abundant in nature and have a limited therapeutic value, except for hydroquinone, which is in plants like bear-berry or bearberry and some types of heather.

Coumarins: affect the vascular system, both arterial and venous circulation, and they are also useful for treating certain skin disorders, such as psoriasis. Some of these are horse-chestnut and angelica.

Tannins: for centuries they have been used for their ability to convert skin into leather, as well as for their internal and external astringent properties. Internally, they are used as an anti-diarrheal and vasoconstrictors. Externally, they are used as vaso-constrictors for certain skin problems, such as dermatosis, and in cosmetics as astringent tonics. They are also antioxidants. Witch-hazel is rich in tannins.

Flavonoids: an important group that is widely distributed in nature, with simple and complex structures. They are often responsible for the coloring of flowers, fruit, and leaves (anthocyanins). They act on the vascular system, strengthening and toning the vein walls. They also have anti-inflammatory and antioxidant effects. Some of the most significant plants containing them are passionflower, ginkgo, milk thistle, and hawthorn.

• Terpenes

Essential oils: complex, liquid mixtures that are volatile. In general, they give plants their unique scent and have an antiseptic, antispasmodic, expectorant, carminative, and digestive effect. At high doses, they are toxic, mainly on the central nervous system. Some can cause topical problems, such as irritation and allergies. Some plants with essential oil are chamomile, peppermint, anise, eucalyptus, and clove.

Sesquiterpenes: traditionally, sesquiterpenes have been considered “bitter” substances. Their main actions are anti-inflammatory, antimicrobial, and appetite stimulating. They include burdock and wormwood.

Triterpenes and steroids: this group includes saponins that have expectorant and diuretic effect, such as licorice root, horse-chestnut, and ginseng root.

• Alkaloids

This is a series of complex and very active nitrogen compounds; even in small doses they have a great effect on the body. They are very effective for different conditions, but if you exceed the recommended dose, they can also be poisonous. There are many plants, such as fumitory, that act using alkaloids.


There are multiple ways to extract and apply active plant substances and benefit from their healing properties. The most appropriate method in each case always depends on the plant and the type of condition being treated. They can be administered internally and applied externally. These are the most common forms of internal administration:

Infusion

Infusion is the simplest way to prepare a remedy using the delicate parts of plants, leaves, flowers, tops, and tender stems. To prepare it, all you have to do is add two teaspoons of the plant to two cups of boiling water. Then let it steep for 10 to 15 minutes and strain. You can drink it hot, lukewarm, or even cold if that is what you prefer. Logically, if you are suffering from a cold, you will want to drink it hot. This remedy can be sweetened with honey, other natural sweetener, or apple juice.

Herbal teas

Herbal teas are probably the most popular way to ingest medicinal plants. They are often made through infusion, decoction, or maceration. You can group several plants together to enhance their effect. Teas are primarily used orally, but as you will see throughout this book, you can also use them topically.

Syrups and potions

To prepare syrups, use simple syrup consisting of water containing 64% sucrose (sugar), and add tinctures or liquid extracts. Syrups are easy and pleasant, and their sweetness masks the bad taste of many plants, which makes it easier to administer to children. Also try using honey instead of sucrose. Potions are similar to syrups but have lower sucrose content.

Juice

Juice is obtained by squeezing the fresh plant. When the plant is too dry or woody, it has to be submerged in hot water. The juice can be ingested or used externally.

Tincture

Tinctures are alcoholic solutions that are prepared by steeping the dried and crushed plant in alcohol at room temperature for two or three days. Alcohol should be suitable for human consumption (never use industrial, denatured, or rubbing alcohol as these are toxic). Dilute them before ingesting (15 to 25 drops in a little water). Due to their alcoholic content, they are contraindicated for individuals suffering from liver disease, pregnant women, children, as well as for people undergoing treatment against alcohol addiction. They can also be used topically.

Powder

Administering in powder form helps you get most of the active ingredients, especially if they are located in the hard parts of the plant (roots, bark, and seeds). Although some people take the powder alone or mix it with food, it is not a very user-friendly method, so take it in capsules or tablets.

Decoction

The proper amount of the plant is placed in hot water and boiled for 2 to 5 minutes. It is then left to macerate for 15 minutes. The resulting liquid is strained and consumed preferably hot, but it can also be ingested warm or cold. It is used to make herbal teas from the hard parts of plants (roots, bark, seeds), which require sustained boiling to release their active ingredients.

Maceration

The plant is placed in an opaque container with the required amount of water at room temperature in a cool, dark place for a certain amount of time, and then the resulting liquid is strained. Generally, the soaking period for delicate parts is about 12 hours, and for the hard parts it is 24 hours. This method is very useful for plants whose active ingredients are thermolabile (altered by heat). Some plants may also be macerated in oil, to be used externally. This preparation should not be confused with extracting its essential oil, which is an active ingredient of the plant itself. Once prepared, they are to be kept in frosted glass containers to avoid losing their effectiveness.


Creams or ointments

Semisolid forms that are generally made up of an emulsified mixture of water and fat or oil. They are applied directly on the skin or mucous membranes, and their active ingredients are used during the preparation process.

Baths

To prepare them, simply add an infusion or decoction (at least 1.5 quart (1.5 liter) of the plant to your bathwater, or you can also dilute 2 to 5 drops of essential oil into bathwater. This method of administration is particularly useful for relieving aching limbs, inflammation, rheumatic pain, and nasal congestion.

The bath can be for the whole body or for the feet, hands, and eyes.

Plasters and poultices

Plasters and poultices consist of applying fresh, dried, or cooked herbs directly on the affected area. They can be applied hot or cold, with a cloth or gauze, or directly after applying oil on the affected area so as to prevent the plant mixture from sticking. Leave on for 5 to 10 minutes; it is better to use several short applications throughout the day rather than a single and prolonged one.

Compresses

Compresses are easier to use than poultices, although their effect is less intense. Moisten a piece of cloth with a few drops of essential oil dissolved in water, an infusion, or decoction or fresh juice, and then apply it (preferably hot) on the affected area for 5 to 10 minutes, depending on the plant.

Vapor

Place the plants or selected essential oil into a container and add boiling water. Then cover your head with a towel and inhale the steam for 20 minutes, eyes closed, trying to breathe normally until it cools off. It is great for clearing your respiratory tract.

Mouth rinses

They can be done with an infusion, decoction, or diluted tincture (1 teaspoon (5 ml) of tincture per ½ cup (100 ml) of water). Do not use very hot or very concentrated liquids, and do not swallow it. They are useful for alleviating conditions of the mouth and throat.


In recent years, there has been growing use of medicinal plants in combination with other conventional medicines. However, keep in mind that self-diagnosing and self-medicating is generally not recommended because although most plants are safe, they are not always harmless. Just as they are likely to improve your health, their misuse or improper combination may have adverse effects and negative interactions with other medications. Many plants have very potent active ingredients, so it is best to consult with a specialist who can recommend adequate treatment and proper dosage.

Side effects and interactions

Medicinal plants work like medications since their therapeutic effect is attributed to their pharmacologically active agents. For this reason, they may cause side effects, mainly due to inadvertent use of the wrong plant species, alteration of the plant, or an overdose. Similarly, drug interactions may occur due to simultaneously administering them with other allopathic medicines.

Responsible use

Although most common plants are harmless, before using them you should be aware that some of them have adverse side effects and negative interactions when combined with certain medications.

Most interactions may lessen or increase the effects of the drug and even cause serious problems. Having the right information helps prevent many problems.

Contraindications

Given that certain medicinal plants can cause negative side effects and interactions, they may be contraindicated in certain situations, so it is important to seek good professional advice before taking any herbal remedy. There are physiological situations where contraindications are more common, such as during pregnancy and lactation. In such cases, using plants that have some level of toxicity is contraindicated. Often, because there is not enough research that ensures complete safety, it is also advised that pregnant and nursing women avoid even those plants that could be considered safe. Children and older adults are two delicate age groups with whom you must take extra precautions.

Written by María Tránsito López & Carlota Mañez in "Medicinal Plants at Home", Skyhorse Publishing, USA, 2015 (original title "Plantas Medicinales en Casa). Digitized, adapted and illustrated to be posted by Leopoldo Costa.