The natural scent of vaginal discharge is typically mild, often described as musky or slightly sour due to beneficial Lactobacilli bacteria. This slightly acidic environment indicates good vaginal health. Noticing an ammonia-like odor can be unsettling, but it often points to manageable causes. Any noticeable change in odor warrants attention, even if the reason is simple.
The Connection Between Ammonia, Urea, and Dehydration
The ammonia smell is frequently linked to external contamination from urine or sweat, which is exacerbated by the body’s natural waste processes. Ammonia itself is a highly toxic byproduct created when the liver breaks down proteins. To safely dispose of it, the liver converts ammonia into a less toxic compound called urea.
Urea is carried through the bloodstream to the kidneys, where it is filtered out and excreted in the urine. When the body is dehydrated, the kidneys conserve water, making the resulting urine highly concentrated with urea. This concentrated urine smells strongly of ammonia, and any residual urine on the vulva or underwear can easily transfer this scent to the discharge.
Sweat also contributes to the ammonia odor because it contains urea excreted through the skin. If sweat mixes with discharge and lingers on skin or clothing, the urea can break down further, intensifying the scent. Addressing hydration and hygiene, such as changing out of sweaty clothes promptly and rinsing the vulva after urination, often resolves the issue.
How Internal Factors Shift Discharge Chemistry
If the ammonia smell persists despite good hydration and hygiene, the cause is a change in the body’s internal chemistry, often due to diet or biological processes. A high-protein diet increases ammonia production because the liver must process more nitrogen waste into urea. Certain nutritional supplements, particularly high doses of water-soluble B vitamins, are also excreted in the urine and can result in a stronger odor.
Changes in the vaginal microflora can also lead to the internal production of ammonia-like odors. Bacterial Vaginosis (BV) is commonly known for causing a “fishy” odor from the release of amines, but it can sometimes present with a more chemical smell. This happens when the overgrowth of certain anaerobic bacteria breaks down proteins in the vaginal discharge, releasing various odorous amines.
Less commonly, a persistent ammonia smell can indicate systemic metabolic issues related to how the body handles urea. Conditions affecting the kidneys or liver can impair their ability to efficiently process and excrete urea. This leads to elevated concentrations in the bloodstream and subsequently in all bodily fluids, including sweat and discharge.
When to Consult a Healthcare Professional
A persistent ammonia odor that does not resolve after simple changes to hydration and hygiene warrants professional advice. Seek consultation if the odor is accompanied by other physical symptoms, which often suggest an underlying infection. These warning signs include pain or burning during urination, itching or irritation of the vulva, and a noticeable change in the discharge’s color or consistency, such as a thin gray or white appearance.
A healthcare provider will begin the diagnostic process by performing a pelvic exam and taking a medical history. They will perform in-office tests, including a vaginal pH test, since a bacterial imbalance like BV often raises the pH above the normal range of 3.8 to 4.5. A wet mount, where a discharge sample is examined under a microscope, can identify signs of infection or the presence of specific organisms.
If an infection is diagnosed, treatment involves prescription medications, such as antibiotics or antifungals. If initial tests rule out a local infection, the physician may order blood or urine tests to evaluate kidney and liver function, addressing the possibility of systemic issues affecting urea metabolism.