What Is Pelargonium Sidoides?

Is the South African geranium a natural cold remedy?

Pelargonium Sidoides syrup, extract, and tincture

Verywell / Anastasia Tretiak

The South African geranium (Pelargonium sidoides), also known as the black geranium or Cape pelargonium, is an herb long used in South African traditional medicine. The root of the plant is typically distilled into an extract and used in cough and cold remedies to alleviate symptoms and reduce the duration of illness.

Proponents claim that the South African geranium can help fight upper respiratory tract infections, including the common cold, bronchitis, and sinusitis.

When used in traditional African medicine, the South African geranium is often referred to as umckaloabo, kaloba, or umcka.

P. sidoides should not be confused with P. graveolens (rose geranium) commonly used to make essential oils for aromatherapy, flavorings, and perfume manufacturing.

What Is Pelargonium Sidoides Used For?

Most of the research related to pelargonium is limited to test tube studies. In this capacity, P. sidoides extracts are known to neutralize certain bacteria and viruses. Whether the same effect can be achieved by ingesting a plant extract remains uncertain. The current evidence is mixed at best.

Colds and Sinusitis

For a 2013 review of studies published in the Cochrane Database of Systematic Reviews, researchers analyzed previously published research and concluded that P. sidoides may decrease the duration of a cold or sinus infection. Despite these findings, the authors acceded that the quality of the studies was low.

In another review published in Academic Pediatrics in 2018, scientists evaluated 11 studies investigating the effectiveness of echinacea, pelargonium, and other herbal medicines in treating respiratory tract infections in kids.

While echinacea (one of the most popular herbal remedies) failed to provide any relief, pelargonium demonstrated "moderate evidence for efficacy" in treating uncomplicated respiratory infections.

Acute Bronchitis

Pelargonium may also help relieve the symptoms of bronchitis, suggests a 2013 review of studies from Germany. As with the previous studies, there was some evidence of a beneficial effect, but the results were largely skewed by the poor quality of the research.

Based on the current evidence, the researchers concluded that an oral extract of P. sidoides may provide modest relief of bronchitis in children. Tablet formulations, by contrast, appear to have no effect.

Further research is needed to substantiate these results.

Possible Side Effects

The safety of pelargonium remedies is largely untested. Commonly cited side effects include stomach upset, nausea, heartburn, or worsening respiratory symptoms.

Pelargonium contains a substance known as coumarin that acts as an anticoagulant (blood thinner). Because of this, you should avoid taking pelargonium with prescription anticoagulants like warfarin as this could lead to excessive bleeding. For the same reason, you should stop taking pelargonium at least two weeks before surgery or a dental procedure.

Pelargonium should also be used with caution in people with autoimmune diseases like psoriasis, rheumatoid arthritis, lupus, and autoimmune hepatitis, according to the European Medicines. Doing so may activate the antibodies that trigger autoimmune symptoms.

Speak with your healthcare provider before using any herbal supplement. Due to the lack of safety research, pelargonium remedies should be not be used by children, pregnant women, or nursing mothers.

Liver Damage

There is also some concern that the long-term or excessive use of pelargonium may cause liver injury.

According to a 2016 study from Germany, P. sidoides was among five herbs suspected of causing liver toxicity when used for medicinal purposes. Others culprits included valerian (Valeriana), peppermint (Mentha piperita), St. John's wort (Hypericum perforatum), and Tasmanian blue gum (Eucalyptus globulus).

In one of the reported cases, liver impairment occurred after using a pelargonium extract for just five days.

If you decide to take pelargonium (especially highly concentrated extracts), call your healthcare provider if you experience any signs of liver toxicity, including fatigue, stomach pain, nausea, dark urine, light stools, or yellow skin or eyes

You should also avoid pelargonium if you have liver disease, are a heavy drinker, or take medications metabolized by the liver.

Dosage and Preparation

There are no guidelines directing the appropriate use of pelargonium supplements. The "safe" dose can vary and may be influenced by age, sex, weight, medications, and general health.

Pelargonium remedies are typically sold as extracts, tinctures, oral suspensions, syrups, or gel caps. As a general rule of thumb, never take more than is prescribed on the product label. Even so, it is not known at what point a pelargonium supplement may become toxic.

Pelargonium is only intended for short-term use, ideally or no longer than five to seven days. The remedies and supplements are easily sourced online and at many health food stores.

What to Look For

Dietary supplements are not subject to rigorous testing and research in the United States. Because of this, the quality of a product can vary, sometimes considerably. To ensure quality and safety, only purchase pelargonium products from a reputable manufacturer with an established brand presence.

While many vitamin manufacturers will voluntarily submit their products for testing by an independent certifying body like ConsumerLab or the U.S. Pharmacopeia (USP), herbal supplement manufacturers rarely do. This can leave you blind as to what is inside a supplement or what may be missing.

For safety sake, avoid buying dried or powdered pelargonium, which may contain pesticides, heavy metals, and other toxins. You should also resist the temptation of making your own tincture or extract as you will be little able to control either the concentration or dose.

Other Questions

Is the South African geranium edible?

Most types of geranium are edible, and the African geranium is no exception. The flowers have a fragrant, slightly peppery flavor, while the leaves have a pleasantly sour, grassy taste.

Fresh geranium can also be made into tea by steeping ¼ cup of finely chopped flowers and leaves with one cup of boiling hot water. Some people believe that sipping geranium tea can help ease indigestion.

However, you should avoid consuming too much fresh geranium as the oxalic acid in the plant (which imparts the flavorful tang) may cause indigestion, nausea, vomiting, and diarrhea. You should also steer clear of any flowers or leaves that may have been sprayed with pesticides or exposed to chemical fertilizers.

When it comes to medicinal use, it is the root of the South African geranium that is believed to be beneficial rather than the stems, leaves, or blossoms.

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

By Cathy Wong
Cathy Wong is a nutritionist and wellness expert. Her work is regularly featured in media such as First For Women, Woman's World, and Natural Health.