The green, pink and L-labelled WithOne boxes all contain fiber, but all three also contain stimulant laxative ingredients. First check whether a laxative is appropriate, then compare the exact formula and flavour. They are not everyday fiber or probiotic supplements.
I'm Irene, a Taiwan-born pharmacist licensed in Japan and working in a Japanese drugstore. I'll help you read beyond “plant-based” on the shelf and keep the sachet dose, water and one-week stop point together.
Sources checked: 13 October 2026. These are Japanese-market oral products; all three are designated Class 2 OTC medicines. Check the actual pack and leaflet when buying.
Before choosing a box
Do not combine them with another laxative, including another WithOne variant, and do not take large doses. If breastfeeding, the labels say not to take the medicine, or to avoid breastfeeding while taking it; discuss a suitable plan before use. Consult a doctor, pharmacist or registered medicine seller first if receiving medical treatment, pregnant or possibly pregnant, or if you have a history of allergic reactions to medicines or similar substances.
Severe abdominal pain, nausea or vomiting also require advice before use. If that describes your current situation, do not start by comparing flavours. A “plant-based” description does not remove these precautions.
Three oral products, three formulas
| Japanese shelf name | Flavour | Formula detail to recognise |
|---|---|---|
| New WithOne / 新ウィズワン | Chocolate | Plantago husk + sennosides + cascara extract |
| New WithOne α / 新ウィズワンα | Peach | Plantago husk + sennosides + Smilax extract; marketed around skin roughness accompanying constipation |
| WithOne L / ウィズワンエル | Yogurt | Plantago husk + sennosides + spore-forming lactic acid bacteria + nicotinamide |
If a family member requested a particular WithOne, match the full name. If choosing for yourself after the safety check, flavour and formula preference can narrow the options; the labels do not establish a universal best product. The L formula still contains a stimulant laxative. The α skin-related wording concerns symptoms accompanying constipation, not a general acne or beauty treatment.
Why the same fiber amount does not make them identical
Amounts in 3 sachets, adult maximum daily amount
| Amounts in 3 sachets, adult maximum daily amount | Plantago husk | Sennosides A+B equivalent | Other active ingredients |
|---|---|---|---|
| New WithOne | 3,000 mg | 32.58 mg | Cascara dry extract 53.6 mg |
| New WithOne α | 3,000 mg | 48 mg | Smilax extract 43.2 mg |
| WithOne L | 3,000 mg | 48 mg | Spore-forming lactic acid bacteria 130 mg; nicotinamide 5 mg |
Plantago husk takes up water and increases stool bulk; sennosides stimulate bowel movement. New WithOne also contains cascara, so the lower sennoside number does not establish that it is gentler overall. The total granule weight also differs: three sachets weigh 3.6 g for New/α and 4.8 g for L. Compare the labelled dose, not a spoonful or the apparent volume of powder.
How much, and how much water?
| Age | One dose, for each of these three products |
|---|---|
| 15 years and over | ¾–1 sachet |
| 11–14 years | ½–⅔ sachet |
| 3–10 years | ¼–⅓ sachet |
| Under 3 | Do not use |
Take 1–3 times daily after meals, without chewing, with a glass of water or warm water, approximately 180 mL. Start with the smallest labelled amount and adjust gradually within the directions according to bowel movements and stool condition. Children need adult supervision. If unsure how to measure a partial sachet, ask the pharmacist rather than estimating with a household spoon.
The shared dose ranges do not mean you should take all three, automatically use three full sachets a day, or keep adding doses because nothing happened immediately. Keep the chosen box and its instructions with you.
The stop point is about one week
If symptoms do not improve after about one week, stop and consult a doctor, pharmacist or registered medicine seller with the product or leaflet. Stop immediately and seek advice for rash, redness, itching, severe abdominal pain, nausea or vomiting after use. Stop and seek advice if diarrhoea persists or worsens; do not wait for the week to end.
A partly used sachet and a similarly named suppository
Fold the opening of a partly used sachet closed, store it and use the remainder as soon as possible. Keep it cool and dry, away from direct sunlight and children; do not transfer to another container or use past expiry. The labels note that sennosides may colour urine yellow-brown or red. Do not use that note to dismiss suspected bleeding or other new symptoms.
ウィズワン坐剤 is a separate suppository for rectal use. It is not another flavour of these granules, and the oral dosing table does not apply. Likewise, old online pages headed only ウィズワン can show different ingredients and age limits; match the current full name on your box.
You do not need the whole range. Choose one suitable product, keep the water and dose instructions close, and reconsider self-treatment if constipation does not improve. For everyday travel adjustments before medicine, see the travel constipation guide.
