Yes, toenail fungus (onychomycosis) can potentially damage your heart, but it's rare and usually involves severe, untreated cases where the fungus enters the bloodstream, spreading from the foot to the heart lining, causing a serious infection called fungal endocarditis, especially in those with weakened immune systems or damaged heart valves. It's crucial to treat toenail fungus to prevent it from becoming a systemic issue, notes this article from Foot and Ankle Specialists of the Mid-Atlantic.
People with toenail fungus are at a higher risk of developing other fungal infections—including those that affect the heart. Toenail fungus can sneak up on you—especially if you're immunocompromised or have preexisting health conditions.
If cellulitis is left untreated, the infection can spread to the bloodstream and become a life-threatening condition for many individuals. This is the most serious result of an untreated toenail fungus, which can be avoided with treatment from a medical professional.
It can cause other problems as well which include: Athlete's foot - results in cracked red skin on the foot. Cellulitis - swollen red skin that needs antibiotic treatment. Onycholysis - toenail separates from the nail bed.
Studies have found that nail particles small enough to enter the lungs contain endotoxins, fungi, fungal arthrospores, and other microbial debris. These particles have been shown to trigger the release of IL-8, which is responsible for attracting neutrophils in inflammatory regions.
If toenail fungus goes untreated, it worsens, causing the nail to thicken, discolor (yellow/brown), become brittle, crumble, and potentially separate from the nail bed, leading to pain, odor, and difficulty walking; it can spread to other nails/skin (athlete's foot) and, in rare cases, lead to serious bacterial infections like cellulitis, especially for those with diabetes or weakened immunity, potentially causing permanent nail damage or systemic issues.
While rare, severe cases of toenail fungus can potentially lead to systemic infection, especially in individuals with compromised immune systems. In such cases, the fungus may enter the bloodstream and spread to other parts of the body, including vital organs.
Circulatory problems linked with heart disease or linked to uncontrolled diabetes can cause ridges, grooves or pitted patterns across toenails. Illness, trauma and these disease conditions serve as stressors that temporarily halt matrix cells that produce new nail material. Have them evaluated by your podiatrist.
You may have a higher risk of getting toenail fungus if you have: Athlete's foot (tinea pedis). Diabetes. Hyperhidrosis (a disorder that makes you sweat a lot).
Fungal diseases
Diagnosis and Tests
If your healthcare provider thinks you may have invasive candidiasis, they'll take a sample of your blood for a blood culture.
To permanently kill toenail fungus, you need professional treatment, with oral antifungal medications like terbinafine (Lamisil) being the most effective for clearing the infection, though they require months of use and liver monitoring. Prescription topical creams (e.g., Jublia, Kerydin) and medicated nail polishes (Penlac) are also options, often used with nail thinning or combined with oral meds. Laser therapy can be effective by heating the fungus but isn't a first-line treatment and lacks strong evidence for a permanent cure.
Fungal skin infections won't usually go away without treatment. If they aren't treated, they could get worse and spread to other parts of your body. You're also more likely to pass them to other people. A fungal nail infection doesn't necessarily need treatment if it's not causing you any problems.
Three early warning signs of heart failure include persistent fatigue/weakness, shortness of breath (especially with activity or lying down), and swelling (edema) in your legs, ankles, and feet, often accompanied by rapid weight gain from fluid buildup, all signaling your heart isn't pumping efficiently enough. Other key indicators are a chronic cough (sometimes with pink mucus) and heart palpitations.
Fungal endocarditis is an infrequent but debilitating condition with a poor prognosis. The disease can present as native valve endocarditis, prosthetic valve endocarditis, inflammation of the endocardial surface, or cardiac device-related infective endocarditis.
Heart failure nails often show nail clubbing, where fingertips enlarge and nails curve downward like an upside-down spoon due to poor oxygen flow, feeling soft and warm, but can also present as blueish tints (cyanosis) or splinter hemorrhages (tiny red lines under nails) from heart infections (endocarditis). Other signs can include Terry's nails (mostly white with a pink tip) or Mees lines (horizontal white bands). These changes signal serious underlying issues, requiring prompt medical evaluation.
A podiatrist can treat the infection effectively and thoroughly with prescription anti-fungal medications and creams. They may alternatively use a special laser that passes light energy through the nail and under the nail bed to target and eradicate the fungi.
Complications. A severe case of nail fungus can be painful and may cause permanent damage to your nails. And it may lead to other serious infections that spread beyond your feet if you have a suppressed immune system due to medication, diabetes or other conditions.
Athlete's foot is caused by the same type of fungi (dermatophytes) that cause ringworm and jock itch. Damp socks and shoes and warm, humid conditions favor the organisms' growth.
Something as simple as a stubbed toe or a badly clipped toenail can lead to a toenail fungal infection. One study found that contracting a fungal infection of the foot can potentially lead to lower limb cellulitis, a more advanced condition that can cause infections in the blood, joints, bones, and heart chambers [6].
7 Unexpected Signs of Heart Problems in Your Feet
The thoracic area – the ball of the foot
This section of the foot corresponds with the thoracic area in the body from the shoulder girdle to the diaphragm. Several vital reflexes are situated here: the heart, lungs, oesophagus, trachea, bronchi, thyroid and thymus glands, diaphragm and solar plexus.
Poisons: Arsenic poisoning may cause white lines and horizontal ridges. Silver intake can cause a blue nail.
The strongest toenail fungus treatments are typically prescription oral antifungal medications like Terbinafine (Lamisil), which have high success rates (70-80%), or combination therapies (oral meds + topicals/laser) for severe cases, as they attack the fungus from multiple angles. Other effective options include laser therapy (hot or cold), which can clear fungus by heating or stimulating the nail, and strong prescription topical lacquers like ciclopirox (Loprox) for less severe infections, requiring diligent application.
Nail changes are among the dermatological disorders associated with liver disease; these include onychomycosis in addition to other changes as onychorrhexis, dystrophic nails, leukonychia, longitudinal striations, brittle nails, clubbing of fingers, and longitudinal melanonychia [8].