What You Need to Know About Herbal Stimulant Laxatives

Herbs known for their laxative effects can be found in a variety of dietary supplements, weight-loss teas, and colon cleansing preparations. Before you think about using one of these products, it is important to be educated about their safety and effectiveness. This overview can help you make an educated decision about whether or not herbal laxatives are right for you.

Types of Herbal Stimulant Laxatives

The following herbs have been associated with having a laxative effect:

• Aloe latex
• Cascara sagrada
• Frangula
• Rhubarb (Rheum)
• Senna

Of the above herbs, senna is the one most often used as an ingredient in commercial laxative preparations, such as Black Draught, ExLax, Fletcher's, Senexon, SennaGen, and Senokot.

How Do They Work?

Herbal laxatives contain chemical compounds called anthranoids, which stimulate cells in the intestine. Anthranoids induce gut motility, which leads to a decrease in transit time.

They also reduce fluid absorption from the intestines into the body and increase fluid secretion in the colon, with the "end result" of softer stools.

Safety Concerns

Ongoing scientific research is looking at the relationship between regular use of anthranoid-containing herbal laxatives and the following health conditions:

Melanosis coli: Regular use of herbal stimulant laxatives has been associated with a condition known as melanosis coli, in which the pigmentation of the lining of the colon changes to a dark-brown color. This change in pigmentation may be seen as early as four months following regular use of anthranoid-containing herbs, and it generally disappears within six months to a year following cessation of the use of these herbs.

Colorectal cancer: The jury is still out as to whether regular use of herbal stimulant laxatives contributes to an increased risk of colorectal cancer. Conflicting results have been seen in animal studies, and studies on humans remain limited. Research is also being conducted to determine whether or not constipation plays a role in terms of increasing the risk of colon cancer.

Side Effects

A variety of side effects have been associated with the use of herbal stimulant laxatives, ranging from mild to severe.

In general, in the cases in which herbal laxatives were linked to severe reactions, such as electrolyte deficiency and even death, the affected individual consumed the herb in excessive amounts.

Seek immediate medical attention (call your healthcare provider or go to the emergency room) if you experience any of the following symptoms:

• Prolonged bouts of diarrhea
• Vomiting
• Severe stomach cramping
• Dizziness, fainting, or excessive fatigue
• Bloody stools or rectal bleeding
• Numbness or tingling in limbs, fingers and toes.
• Irregular or fast heart rate (tachycardia or arrhythmia)

The Bottom Line

Herbal stimulant laxatives appear to be an appropriate choice for the short term treatment of constipation, as long as you take care to do the following:

• Read labels to make sure you know what ingredients you are introducing into your body.
• Carefully follow the dosage recommendations.

For prolonged or chronic constipation (fewer than three bowel movements a week or difficult passing stools), consider alternative treatments such as increasing fluid and fiber intake, dietary changes, and bowel retraining. Herbal laxatives are not for long-term use.

If you are pregnant or breastfeeding, talk to your healthcare provider before taking an herbal stimulant laxative. 

Additionally, some herbal stimulant laxatives may interact with other medications that you are taking. If you are taking prescription or nonprescription drugs, be sure to check with your healthcare provider or pharmacist before taking herbal stimulant laxatives.