Alexandrian Senna

This genus of about 260 species of perennials, shrubs, and trees occurs mainly in the tropics and subtropics. It is often included in Cassia. A few species are grown as ornamentals in warm regions or in greenhouses in temperate regions. Senna marilandica is one of the hardiest, but needs a sheltered situation outdoors in cold areas. The roots were used as a laxative by the Cherokee, and also to relieve fever, cramps, and heart problems. The use of S. alexandrina as a laxative was introduced to Europe by Arab physicians in the 9th and 10th centuries. Senna alexandrina is the main ingredient of most laxative preparations, but various other species also contain laxative anthraquinone glycosides (sennosides). The pods of S. fistula (pudding pipe tree) are up to 50cm (20in) long and contain a black pulp, which is used as a mild for S. alexandrina. Sennas are useful for a wide range of other complaints, ranging from ringworm (S. alata, S. obtusifolia, and S. sophera) to venereal disease (S. sieberiana and S. surattensis). Senna reticulata yields the antibiotic Rhein-cassic acid, which is effective against various bacterial and fungal infections. Senna obtusifolia (Sickle senna) was recorded in Chinese medicine druing the later Han dynasty (CE25-220). It is used in patent medicines and to treat hypertension, high cholesterol leves, constipation, skin diseases, and eye disorders. The seeds of S. laevigata, S. obtusifolia, S. occidentalis, and S. sericea are used as a coffee substitute in various parts of the world.

Native to Eurasia and cultivated in India and the Middle East, senna, a member of the pea family, is valued for the purgative action of its leaves and pods. Both contain substances called anthranoids, which strongly stimulate contractions in the colon and speed elimination. Because senna pods contain about twice as many antharanoids as the leaves, the leaves are considered a safer choice.

Shrubby perennial with pale green, pinnate leaves, 5-15cm (2-6in) long, divided into 3-8 pairs of pointed, lanceolate leaflets. Yellow to tawny-yellow flowers, about 1cm (½in) acorss, are borne in axillary racemes, to 20cm (8in)long, in spring and summer, followed by straight pods, to 7cm (3in) long.

Common Name:
Alexandrian Senna
Other Names:
Alexandria Senna, India Senna, Khartoum Senna, Senna, Tinnevelly Senna
Botanical Name:
Senna alexandrina syn. Cassia angustifolia, C. senna, Cassia spp.
Family Name:
Native Location:
Arabia, Djibouti, Somalia
Well-drained soil in sun. Senna marilandica needs rich, moist, sandy oil. Pot-grown plants may be damaged by root mealy-bugs.
By seed sown in spring at 18-24°C (64-75°F); by semi-ripe cuttings in summer. Prune to shape and remove dead or badly placed growths in early spring.
Leaves are picked before and during flowering; pods are collected in autumn when ripe. Both are dried for use in infusions, powders, tablets, and tinctures.
1m (3ft)
50-60cm (20-24in)
Min. 5°C (41°F)
Parts Used:
Leaves (fan xie ye), pods.
A sweet, cooling, laxative herb with a tea-like aroma and anti-bacterial effects.
Medicinal Uses:
Internally for constipation. Usually prescribed with carminatives (such as Coriandrum sativum see, Coriander, or Zingiber officinale see, Ginger) to reduce griping.
To treat constipation, liver disease, jaundice, anemia, and typhoid fever. Germany's Commission E has approved the use of senna to treat constipation.
Typical Dose:
A typical dose of senna may range from 0.1 to 0.2 gm herb mixed with 150 ml hot water, steeped for 10 minutes, strained and taken as a tea.
Possible Side Effects:
Senna's side effects include nausea, vomiting, cramping, diarrhea, flatulence, irregular heartbeat, and kidney damage.
Drug Interactions:
Taking senna with these drugs may increase the risk of hypokalemia (low levels of potassium in the blood):
Acetazolamide, (Apo-Acetazolamide, Diamox Sequels)
Azosemide, (Diat)
Bepridil, (Vascor)
Bumetanide, (Bumex, Burinex)
Chlorothiazide, (Diuril)
Chlorthalidone, (Apo-Chlorthalidone, Thalitone)
Ethacrynic Acid, (Edecrin)
Etozolin, (Elkapin)
Flecainide, (Tambocor)
Furosemide, (Apo-Furosemide, Lasix)
Hydrochlorothiazide, (Apo-Hydro, Microzide)
Hydroflumethiazide, (Diucardin, Saluron)
Indapamide, (Lozol, Nu-Indapamide)
Insulin, (Humulin, Novolin R)
Mannitol, (Osmitrol, Resectisol)
Mefruside, (Baycaron)
Methazolamide, (Apo-Methazolamide)
Methyclothiazide, (Aquatensen, Enduron)
Methylprenidsolone, (Depo-Medrol, Medrol)
Metolazone, (Mykrox, Zaroxolyn)
Olmesartan and Hydrochlorothiazide, (Benicar HCT)
Polythiazide, (Renese)
Prednisone, (Apo-Prednisone, Deltasone)
Sildenafil, (Viagra)
Torsemide, (Demadex)
Trichlormethiazide, (Metatensin, Naqua)
Urea, (Amino-Cerv, UltraMide)
Xipamide, (Diurexan, Lumitens)
Taking senna with these drugs may increase the risk of arrhythmia (irregular heartbeat):
Acebutolol, (Novo-Acebutolol, Sectral)
Adenosine, (Adenocard, Adenoscan)
Amiodarone, (Cordarone, Pacerone)
Bepridil, (Vascor)
Bretylium, (Bretylium)
Digitalis, (Digitek, Lanoxin)
Diltiazem, (Cardizem, Tiazac)
Disopyramide, (Norpace, Rhythmodan)
Dofetilide, (Tikosyn)
Esmolol, (Brevibloc)
Flecainide, (Tambocor)
Ibutilide, (Corvert)
Insulin, (Humulin, Novolin R)
Lidocaine, (Lidoderm, Xylocaine)
Methylprednisolone, (Depo-Medrol, Medrol)
Mexiletene, (Mexitil, Novo-Mexiletine)
Moricizine, (Ethmozine)
Phenytoin, (Dilantin, Phenytek)
Prednisone, (Apo-Prednisone, Deltasone)
Procainamide, (Procanbid, Pronestyl-SR)
Propafenone, (Rhythmol, GenPropafenone)
Propranolol, (Inderal, InnoPran XL)
Quinidine, (Novo-Quinidin, Quinaglute DuraTabs)
Sildenafil, (Viagra)
Sotalol, (Betapace, Sorine)
Tocainide, (Tonocard)
Verapamil, (Calan, Isoptin SR)
Taking senna with these drugs may decrease blood levels of estrogen:
Cyproterone and Ethinyl Estradiol, (Diane-35)
Estradiol, (Climara, Estrace)
Estradiol and Norethindrone, (Activella, CombiPatch)
Estradiol and Testosterone, (Climacteron)
Estrogens, Conjugated A/Synthetic, (Cenestin)
Estrogens, Conjugated/Equine, (Premarin, Congest)
Estrogens, Conjugated/Equine, and Medroxyprogesterone, (Premphase, Prempro)
Estrogens (Esterified), (Estratav, Menest)
Estrogens (Esterified) and Methyltestosterone, (Estratest, Estratest H.S.)
Estropipate, (Ogen, OrthoEst)
Ethinyl Estradiol, (Estinyl)
Ethinyl Estradiol and Desogestrel, (Cyclessa, Ortho-Cept)
Ethinyl Estradiol and Ethynodiol Diacetate, (Demulen, Zovia)
Ethinyl Estradiol and Etonogestrel, (NuvaRing)
Ethinyl Estradiol and Levonorgestrel, (Alesse, Triphasil)
Ethinyl Estradiol and Norelgestromin, (Evra, Ortho Evra)
Ethinyl Estradiol and Norethindrone, (Brevicon, Ortho-Novum)
Ethinyl Estradiol and Norgestimate, (Cyclen, Ortho Tri-Cyclen)
Ethinyl Estradiol and Norgestrel, (Cryselle, Ovral)
Mestranol and Norethindrone, (Necon 1/50, Ortho-Novum 1/50)
Polyestradiol, (Polyestradiol)
Taking senna with these drugs may increase the drug's therapeutic and adverse effects:
Cascara, (Cascara)
Docusate, (Colase, Ex-Lax Stool Softener)
Docusate and Senna, (Peri-Colace, Senokot-S)
Lactulose, (Constulose, Enulose)
Magnesium Hydroxide, (Dulcolax Milk of Magnesia, Phillip's Milk of Magnesia)
Magnesium Hydroxide and Mineral Oil, (Phillips' M-O)
Magnesium Citrate, (Citro-Mag)
Magnesium Oxide, (Mag-Ox 400, Uro-Mag)
Magnesium Sulfate, (Epsom Salts)
Polyethylene Glycolelectrolyte Solution, (Colyte, MiraLax)
Psyllium, (Metamucil, Reguloid)
Sorbitol, (Sorbilax)
Lab Test Alterations:
  • May decrease blood levels of estriol.
  • May decrease twenty-four-hour urine tests of estriol.
  • May reduce serum potassium levels.
  • May confound results of diagnostic urine tests that rely on color change by discoloring urine (pink, red, purple, or orange.
Disease Effects:
  • May worsen potassium deficiency and electrolyte imbalances.
  • May worsen diarrhea and dehydration.
  • May worsen gastrointestinal ailments.
  • May worsen heart ailments by causing an electrolyte imbalance.
Supplement Interactions:
Leaves may cause contact dermatitis.
Excess or frequent usage may cause nausea, vomiting, abdominal pain, inflammation of the gastrointestinal tract, and deterioration in bowel function (laxative dependency).
Contraindicated during pregnancy, and for colitis or spastic constipation.
Encyclopedia of Herbs ~ Deni Bown ~ Copyright © 1995, 2001, Doring Kindersley Limited ~ pg. 366
The Essential Herb-Drug-Vitamin Interaction Guide by Geo. T. Grossberg,MD and Barry Fox,PhD Copyright©2007 Barry Fox,PhD Pp. 420-422