Toenail fungus, medically known as onychomycosis, may be an embarrassing condition, but it’s relatively common. While there are plenty of home remedies ready and available, toenail fungus can be a hassle to get rid of, and treatment can be a long and winding process, especially as the condition worsens and spreads. This is why it’s best to seek treatment at the first signs of a fungal infection, before the fungus spreads to neighboring nails. It’s fairly easy to spot the earliest visible signs of a fungal infection. Here are the main toenail fungus symptoms to watch out for:

Scaling under the nail (subungual hyperkeratosis)
White or yellow streaks on or under the nail (lateral onychomycosis)
Crumbling corners or tip of the nail (distal onychomycosis)
Yellow spots at the bottom of the nail (proximal onychomycosis)
Flaking white areas on the nail’s surface
Loosening or complete loss of the nail

While there are other nail conditions and infections that mimic the symptoms of fungal nail infections, there are also common, yet highly evident, signs that prove you are definitely affected by toenail fungus. Toenail fungus can affect parts of the nail, the entirety of the nail, or even several nails at a time. If you notice one or more of the following, you may be suffering (or about to suffer) from toenail fungus:

A white or yellow spot under the nail
White or yellow streaks on the nail
A whitish to yellow-brown discoloration on the nail
A darker color nail caused by debris build-up under the nail
Distorted or warped nail
Loose nail or nail lifting off the nail bed
Thickened nail
Brittle and crumbling nails
A foul smell or odor coming from the nail

Going back, there are multiple nail conditions that can be mistaken for toenail fungus. If you are unsure whether you are experiencing symptoms of toenail fungus or any of these other nail conditions, it’s best to seek advice from a medical professional before undergoing treatment. Here are some nail conditions that tend to mimic toenail fungus symptoms:

Lines and ridges

These are relatively common and can be considered normal. Lines and ridges on your nails are harmless, and can be caused by multiple factors including nail biting and chemotherapy.

Senile nails

This happens due to aging. As you age, your nails become brittle and develop ridges. The nail layers also tend to separate at the end of the nails. Senile nails are also relatively harmless.

Whitish or yellowing nails

This usually occurs due to onycholysis (not to be confused with onychomycosis), or the painless separation of the nail from the nail bed. The off-white and yellow color you see is the air beneath the nails. Persistency of this condition can make your nails susceptible to a fungal infection.

Red or black nails

This is due to hematoma, or blood collecting under the nail. This is usually caused by trauma (such as stubbing your toe). The discolored area will grow out, and can be trimmed off.

Green nails

This is caused by pseudomonas bacteria, a type of bacteria that causes infections, that grow under a nail that has been partially separated from the nail bed. This infection may cause your nail to emit a foul odor.

Pitted nails

This is usually associated with psoriasis or other skin conditions that affect the nail matrix or the area under the skin just behind the nail. The affected nails can also be a tan color.

Swelling and/or redness of the skin around the nails

Also called paronychia, this is caused by an infection of the skin at the cuticle, typically caused by bacteria. Chronic paronychia occurs when a cuticle becomes inflamed or irritated over time.

Chronic nail trauma

Certain damage to the nails caused by repetitive trauma or athletic endeavors (such as starting and stopping, and kicking) can look a lot like a fungal infection.