Three of these five are sennosides 8.6mg, the same standardized dose, at between roughly 2 and 17 cents a tablet. Two do not state their dose at all.
MAJOR
Why we like it
Senokot
Why we like it
Prunelax
Why we like it
GenCare
Why we like it
Senokot
Why we like it| Product | Rank | Brand | Best For | Score |
|---|---|---|---|---|
| MAJOR Senna 8.6 mg Natural Vegetable Laxa... | #1 | MAJOR | Best Value | 9.8 |
| Senokot Regular Strength Laxatives for Co... | #2 | Senokot | Best Known Brand | 9.6 |
| Prunelax Ciruelax Regular Strength Laxati... | #3 | Prunelax | Best Stated Dietary Exclusions | 9.4 |
| GenCare Senna Laxative 8.6mg Tablets, Nat... | #4 | GenCare | Best Mid-Size Bottle | 9.3 |
| Senokot Extra Strength Senna Laxative Tab... | #5 | Senokot | Highest Stated Strength | 9.1 |
Buyer checklist
We read all five listings off the live Amazon.com pages, bullets and detail tables both, and compared them on the three things that are stated and checkable: the active ingredient and its amount, the number of tablets in the package, and the package directions as printed. Because senna is an over-the-counter drug sold under a standardized monograph rather than a dietary supplement, the active ingredient is directly comparable between brands in a way supplement ingredients usually are not, which is what makes a cost-per-tablet comparison meaningful here. Where a listing did not state a milligram figure we have said so rather than assuming it matched the others. We have not taken any of these products, we are not recommending that anyone take them, and nothing here is dosing guidance: the package directions we quote are quoted as the package's own, and the decision to use a stimulant laxative, at what amount and for how long, belongs to you and a pharmacist or doctor who knows your situation and your other medicines. Constipation that does not resolve, or that comes with pain, bleeding or vomiting, is a reason to seek medical help rather than to buy a larger bottle.
Because senna tablets are sold in the United States under an over-the-counter drug monograph, which specifies the active ingredient and the permitted amounts rather than leaving them to each manufacturer. That is why three of these five state exactly sennosides 8.6mg, and why GenCare can print Compares to Senokot on its label without that being a vague claim. It is the same situation as generic ibuprofen or generic antihistamines: the regulated active ingredient is the same, and what a brand sells on top of it is packaging, familiarity and distribution. It also means a cost-per-tablet comparison across these products is genuinely apples to apples, which is rare.
On the evidence of these labels, mostly familiarity and package size rather than a different drug. Senokot is the long-established brand and is made by a named pharmaceutical company, Atlantis Consumer Health Care, which some buyers reasonably value, and its listing is the one that spells out the one-week warning. MAJOR is also a pharmaceutical manufacturer, selling the same 8.6mg sennosides in a 1000-count bag at a fraction of the per-tablet cost. The practical catch at the cheap end is quantity: a thousand tablets of a product that should not be used for more than a week at a time is far more than a household needs, and tablets do expire.
It is the standard warning on stimulant laxatives and it is the single most important thing on any of these packages. Senna works by stimulating the bowel wall rather than by softening stool or adding fluid, and prolonged daily use of a stimulant laxative is specifically what the labels warn against, which is why Senokot's listing says not to use it longer than one week without consulting a doctor. If constipation is persistent rather than occasional, the question is why, and that is a medical question with a lot of possible answers. Buying a bigger bottle is the one response the labels themselves rule out.
We do not know, and it is a fair thing to notice. Prunelax's active-ingredient field reads simply Senna and its bullets refer to senna leaf extracts without a figure, while Senokot Extra Strength describes a standardized senna concentrate that is extra strength without saying extra strength relative to what, numerically. Both are regulated products and both carry a Drug Facts panel on the physical package where the amount must appear, so the information exists; it is the marketplace listing that omits it. The practical consequence is that you cannot compare either one on dose from the listing alone, and if dose matters to you, the Drug Facts panel or a pharmacist is where to get it.