Short answer: The CombiPatch Patient Information says that if you forget to apply a new CombiPatch, you should apply a new one as soon as possible. The Instructions for Use add that stopping or forgetting a patch may bring spotting or bleeding, and symptoms may come back. CombiPatch is changed every 3 to 4 days, and only one patch is worn at a time.
| Situation | What the label says |
|---|---|
| Schedule | A new patch every 3 to 4 days (twice weekly) on the lower abdomen (Dosage and Administration) |
| Forgot to apply a new patch | Apply a new CombiPatch as soon as possible (Patient Information) |
| After a late change | Not stated |
| Patch fell off | Reapply the same patch to another area of the lower abdomen, or a new one; keep the original schedule (Dosage and Administration) |
| How many at once | Only 1 patch during each 3- to 4-day interval (Dosage and Administration) |
| Missed or stopped patches | May bring spotting or bleeding, and symptoms may come back (Instructions for Use) |
Patient Information: "If you forget to apply a new CombiPatch, you should apply a new CombiPatch as soon as possible."
Instructions for Use: "If you stop using your CombiPatch or forget to apply a new CombiPatch as scheduled you may have spotting, or bleeding, and your symptoms may come back."
The label does not say whether the next change after a late patch moves or stays on the original days.
Dosage and Administration: "If a system should fall off, the same system may be reapplied to another area of the lower abdomen. If necessary, a new transdermal system may be applied, in which case, the original treatment schedule should be continued. Only 1 system should be worn at any 1 time during the 3- to 4-day dosing interval."
The Patient Information says bathing, swimming or showering will not affect CombiPatch.
Clinical Pharmacology says estradiol has a short elimination half-life of about 2 to 3 hours, and serum estradiol returns to untreated postmenopausal levels within 4 to 8 hours after the patch is removed. Norethindrone has a reported half-life of 6 to 8 hours and falls below 50 pg/mL within 48 hours after removal.
This page summarizes FDA labeling. It is not personalized medical advice; confirm what to do with your prescriber or pharmacist.