D-83-1

For the assessment of delayed-type hypersensitivity (DTH), the standard adult dose of Candida Albicans antigen is 0.1 mL.

• Administration: The dose is administered strictly via the intradermal route. This involves using a tuberculin syringe to inject the solution just below the surface of the skin, usually on the volar surface (inside) of the forearm.
• Observation: A successful injection should produce a small, distinct bleb (pale elevation of the skin) approximately 6-10 mm in diameter.
• Reading the Results: The reaction must be evaluated by a healthcare professional 48 to 72 hours after the injection. A positive reaction is generally defined as an area of induration (palpable hardness) measuring 5 mm or greater in diameter. Redness (erythema) without hardness is not considered a positive result.

Candida Albicans antigen is approved for use in pediatric patients. The dosage is generally the same as the adult dose:

• Children (All Ages): 0.1 mL administered intradermally.
• Considerations: In very young infants (under 6 months of age), the immune system may not yet be sufficiently developed to show a response to Candida, even if they are healthy. Therefore, results in infants must be interpreted with extreme caution.

Renal Impairment

No dosage adjustments are required for patients with kidney disease. Because the drug is administered locally in a minute volume and is not cleared by the kidneys, renal function does not affect the safety or efficacy of the test.

Hepatic Impairment

No dosage adjustments are required for patients with liver disease. The metabolism of the fungal extract occurs at the site of injection and does not involve hepatic pathways.

Elderly Patients

While the standard 0.1 mL dose is used, healthcare providers should be aware that immune responsiveness naturally declines with age (immunosenescence). A smaller or absent reaction in an elderly patient may reflect a natural age-related decline in T-cell function rather than a specific disease state.

This medication is not 'taken' by the patient in the traditional sense. It is a diagnostic procedure performed by a clinician.

• Preparation: The skin site (usually the forearm) is cleaned with an alcohol swab and allowed to dry.
• Injection: The needle is inserted at a 5 to 15-degree angle. The patient may feel a slight stinging or burning sensation as the bleb forms.
• Aftercare: Do not apply bandages, creams, or lotions to the injection site. Do not scratch or rub the area, as this can cause irritation that might be mistaken for a positive test result.
• Storage: Vials must be stored in a refrigerator at 2°C to 8°C (36°F to 46°F). They should never be frozen.

Since this is a one-time diagnostic test, a 'missed dose' is not applicable. However, if a patient fails to return within the 48-to-72-hour window for the result to be read, the test is considered invalid and must be repeated. A repeat test should generally be performed on the opposite arm.

An overdose of Candida Albicans antigen is highly unlikely due to the small volume (0.1 mL) administered. However, if a significantly larger volume were accidentally injected:

• Signs: Severe local inflammation, blistering, or skin necrosis (tissue death) at the injection site. In highly sensitive individuals, systemic symptoms like hives or wheezing could occur.
• Emergency Measures: If a systemic allergic reaction occurs, epinephrine and antihistamines should be administered immediately. Localized over-reactions are managed with cool compresses and, in some cases, topical corticosteroids.

> Important: Follow your healthcare provider's dosing instructions. Do not attempt to self-administer this product or interpret your own results.

Most patients receiving the Candida Albicans antigen test will experience some level of localized reaction, as this is the intended purpose of the diagnostic tool. Common effects include:

• Local Erythema (Redness): This is a normal part of the inflammatory response. It usually appears within 24 hours and peaks around 48-72 hours. It may feel slightly warm to the touch.
• Induration (Hardness): A firm, raised bump at the site of injection. This is the primary marker of a positive test. It may feel like a small, hard pea under the skin.
• Pruritus (Itching): Many patients report mild to moderate itching at the injection site. This is caused by the release of histamines and other inflammatory mediators during the T-cell response.
• Local Tenderness: The site may be slightly sore when touched or when clothing rubs against it.

• Vesiculation (Blistering): In individuals who are highly sensitive to Candida, the immune response may be vigorous enough to cause small, fluid-filled blisters at the injection site.
• Hyperpigmentation: After the reaction fades, some patients (particularly those with darker skin tones) may notice a temporary darkening of the skin at the injection site that can last for several weeks.
• Lymphadenopathy: Occasionally, the lymph nodes near the injection site (e.g., in the armpit) may become slightly swollen or tender as they process the antigen.

• Skin Necrosis: In extremely rare cases of hyper-reactivity, the skin at the center of the injection site may break down or form an ulcer. This requires medical attention to prevent infection.
• Fainting (Vasovagal Syncope): This is usually a reaction to the needle stick itself rather than the Candida extract.
• Scarring: While rare, a very severe local reaction or subsequent infection of the site could lead to a small permanent scar.

While Candida Albicans antigen is administered in very small amounts, systemic allergic reactions are possible.

> Warning: Stop the procedure (if still ongoing) and call your doctor or seek emergency care immediately if you experience any of the following:

• Anaphylaxis: A life-threatening allergic reaction characterized by a sudden drop in blood pressure, difficulty breathing, and loss of consciousness.
• Angioedema: Severe swelling of the lips, tongue, or throat, which can obstruct the airway.
• Generalized Urticaria (Hives): The appearance of itchy welts all over the body, not just at the injection site.
• Wheezing or Chest Tightness: Signs of bronchial constriction.
• Tachycardia: A rapid or pounding heartbeat combined with a feeling of lightheadedness.

There are no known long-term systemic side effects associated with a single diagnostic dose of Candida Albicans antigen. The substance is rapidly broken down by the body's immune cells. The only potential long-term effect is a localized change in skin pigmentation at the injection site, which almost always resolves over time.

No FDA black box warnings are currently issued for Candida Albicans antigen. However, the product labeling contains strong precautions regarding the risk of systemic allergic reactions and the necessity of having emergency equipment (like epinephrine) available during administration.

Report any unusual symptoms to your healthcare provider. If you notice signs of infection at the injection site (increasing pain, pus, or red streaks spreading from the site), contact your doctor immediately.

Candida Albicans antigen is intended for intradermal use only. It must never be injected intravenously, as this could cause a severe systemic inflammatory response or anaphylaxis. Because the extract is derived from a biological source, there is a theoretical risk of variability in potency, although modern manufacturing processes (such as those used for Candin®) are highly standardized to minimize this risk.

Patients should be observed for at least 20 to 30 minutes following the injection to monitor for immediate allergic reactions. If a patient has a known history of severe allergy to yeast or yeast-containing products, the healthcare provider must weigh the diagnostic benefits against the risk of a severe reaction.

No FDA black box warnings for Candida Albicans. Unlike some therapeutic allergenic extracts used for 'allergy shots' (immunotherapy), the diagnostic use of Candida Albicans involves a much smaller, single dose, which significantly reduces the risk profile compared to products that require a black box warning.

• Allergic Reactions / Anaphylaxis Risk: Although rare, any foreign protein injected into the body carries the risk of anaphylaxis. Facilities administering this test must have an 'anaphylaxis kit' containing epinephrine (1:1000), antihistamines, and oxygen.
• Bleeding Disorders: Patients with thrombocytopenia (low platelets) or those on anticoagulant therapy (blood thinners like warfarin or apixaban) may experience significant bruising or bleeding at the injection site. The injection should be performed with a very fine-gauge needle, and pressure should be applied for an extended period afterward.
• Infection Risk: As with any procedure that breaks the skin, there is a minor risk of localized infection. Sterile technique is mandatory.
• Anergy Interpretation: A negative test result does not always mean the patient has a diseased immune system. Some healthy individuals simply do not react to Candida. Diagnosis of immunodeficiency should never be based on a single skin test.

There are no ongoing laboratory tests (like blood counts) required for the use of Candida Albicans antigen. The primary 'monitoring' is the physical examination of the injection site by a healthcare professional 48 to 72 hours post-administration. If the test is being used to monitor the progression of a disease (like HIV), it may be repeated at intervals determined by the specialist.

Candida Albicans antigen does not cause drowsiness or cognitive impairment. Patients are generally safe to drive or operate machinery immediately after the 20-30 minute observation period, provided they do not feel faint from the injection process.

There is no direct interaction between alcohol and Candida Albicans antigen. However, heavy alcohol consumption can acutely suppress certain aspects of the immune response, which might theoretically lead to a 'false negative' or diminished skin test result. It is best to avoid excessive alcohol for 24 hours before and 48 hours after the test.

As this is a one-time diagnostic tool, there is no 'discontinuation' or 'tapering' required. There is no risk of withdrawal syndrome.

> Important: Discuss all your medical conditions, especially any history of fainting or severe allergies, with your healthcare provider before starting Candida Albicans testing.

There are no drugs that are strictly 'contraindicated' in the sense of causing a lethal chemical reaction with Candida Albicans antigen. However, certain drugs make the test clinically useless because they prevent the immune system from reacting:

• High-Dose Systemic Corticosteroids: Drugs like prednisone (usually doses >20mg/day) or dexamethasone significantly suppress T-cell activity. If a patient is on these medications, the Candida skin test will likely be negative, regardless of the patient's actual immune health. The test should be delayed until the steroid dose is reduced or discontinued, if medically feasible.

• Immunosuppressants: Medications used to prevent organ transplant rejection (e.g., cyclosporine, tacrolimus, mycophenolate mofetil) or to treat autoimmune diseases (e.g., azathioprine) will blunt the DTH response.
• Biologic Response Modifiers: TNF-alpha inhibitors (e.g., adalimumab, etanercept) and other biologics used for rheumatoid arthritis or psoriasis can interfere with the cytokine cascade required for a positive skin test.
• Chemotherapy: Cytotoxic agents that lower white blood cell counts (neutropenia/lymphopenia) will result in a diminished or absent reaction.

• H1-Antihistamines: While antihistamines (like diphenhydramine or loratadine) primarily block the 'immediate' (Type I) allergic response (the 'wheal and flare'), they may slightly reduce the redness (erythema) associated with the DTH response. They generally do not affect the 'induration' (the hard bump), which is the most important part of the reading.
• NSAIDs: High doses of non-steroidal anti-inflammatory drugs (like ibuprofen or naproxen) may theoretically reduce the localized swelling, though this is rarely clinically significant for the test interpretation.

There are no known interactions with specific foods, including dairy, grapefruit, or caffeine. The diagnostic efficacy of the intradermal injection is not affected by the patient's diet.

• Echinacea and Astragalus: These supplements are often taken to 'boost' the immune system. While there is no definitive data, they could theoretically enhance the local inflammatory response.
• St. John's Wort: No known interaction.
• Immunosuppressive Herbs: High doses of herbs with purported immunosuppressive properties (sometimes used in traditional medicine) could potentially lead to a false-negative result.

• Tuberculin Skin Test (PPD): Candida Albicans antigen is often administered at the same time as a PPD test but at a different site (e.g., the other arm). It does not interfere with the PPD result; rather, it helps interpret it by checking for anergy.
• Viral Vaccines: Administration of live virus vaccines (like MMR or Varicella) can temporarily suppress cellular immunity for up to 4-6 weeks. The Candida skin test should be performed either on the same day as the vaccine or delayed by at least one month to avoid a false-negative result.

> Important: Tell your doctor about ALL medications, supplements, and herbal products you are taking, especially those that affect your immune system.

Candida Albicans antigen must NEVER be used in the following circumstances:

• Previous Severe Systemic Reaction: If a patient has ever experienced anaphylaxis or a severe systemic allergic reaction to a previous Candida Albicans skin test, they must not receive it again. The risk of a repeat, potentially fatal reaction outweighs any diagnostic benefit.
• Known Hypersensitivity to Yeast: Since the extract is derived from Candida albicans, individuals with a documented, severe allergy to yeast-derived products are at high risk.
• Acute Infection at the Site: The injection should not be performed through skin that is currently infected, burned, or affected by active eczema or psoriasis, as this will make the results impossible to read and may worsen the skin condition.

In these cases, the healthcare provider will perform a risk-benefit analysis:

• Bleeding Disorders: In patients with severe hemophilia or very low platelets, the risk of a hematoma (a large bruise) at the injection site is high.
• Recent Live Vaccine Administration: As mentioned, a live vaccine within the last 4 weeks may cause a false-negative result. The test is not 'dangerous' in this case, but it may be inaccurate.
• Pregnancy: While not strictly contraindicated, it is usually avoided unless the diagnostic information is critical for managing a serious maternal illness.

• Other Fungal Extracts: Patients allergic to other fungi (like Saccharomyces or Aspergillus) may show cross-reactivity. However, because this is a diagnostic test, 'cross-sensitivity' often manifests as a positive test result, which is generally the goal of the procedure, provided it does not become a systemic allergic reaction.

> Important: Your healthcare provider will evaluate your complete medical history, including any history of 'needle phobia' or fainting, before prescribing Candida Albicans antigen testing.

Pregnancy Category C: Animal reproduction studies have not been conducted with Candida Albicans antigen. It is also not known whether it can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity.

• Risks: The primary concern during pregnancy is the risk of a systemic allergic reaction (anaphylaxis), which could lead to maternal hypoxia (low oxygen) and subsequent fetal distress.
• Clinical Use: Candida Albicans antigen should be given to a pregnant woman only if clearly needed. Most clinicians prefer to delay elective diagnostic skin testing until after delivery.

It is not known whether the components of Candida Albicans antigen are excreted in human milk. However, because the dose is minute (0.1 mL) and administered intradermally, systemic absorption is negligible. It is generally considered unlikely to pose a risk to the nursing infant. The decision to test should consider the mother's clinical need and the benefits of breastfeeding.

• Approved Use: Candida Albicans antigen is safe and effective for use in children to assess cellular immunity.
• Efficacy in Infants: In infants under 6 months of age, a negative result is common and does not necessarily indicate an immune deficiency, as the child may not have had enough environmental exposure to Candida to develop a DTH response.
• Safety: The side effect profile in children is similar to that in adults, primarily consisting of local redness and itching.

• Immunosenescence: Patients over age 65 often show reduced responses to DTH antigens. Studies have shown that the diameter of induration may be smaller in the elderly compared to younger adults.
• Interpretation: A negative result in an elderly patient should be interpreted cautiously and in the context of their overall clinical picture.
• Polypharmacy: Elderly patients are more likely to be on medications (like steroids for arthritis) that could interfere with the test results.

There are no specific restrictions or dosage changes for patients with renal impairment. The test is safe for patients on hemodialysis, though it is worth noting that end-stage renal disease (ESRD) itself can sometimes cause a state of mild anergy.

There are no specific restrictions or dosage changes for patients with hepatic impairment. The test is safe for patients with cirrhosis, though severe liver disease may also contribute to a suppressed immune response (anergy).

> Important: Special populations require individualized medical assessment. Always inform your doctor if you are pregnant or planning to become pregnant before any diagnostic procedure.

Candida Albicans antigen acts as a diagnostic 'probe' for the cell-mediated immune system. Unlike drugs that bind to specific receptors to change physiological function, this antigen triggers a Type IV Delayed-Type Hypersensitivity (DTH) reaction.

The molecular process involves:

1. 1Antigen Presentation: The Candida proteins are captured by dermal dendritic cells.
2. 2T-Cell Recruitment: These cells travel to local lymph nodes and present the antigen to sensitized T-lymphocytes.
3. 3Cytokine Release: Activated T-cells migrate back to the injection site and release cytokines (IFN-gamma, TNF-alpha).
4. 4Inflammation: These cytokines increase vascular permeability and recruit macrophages, leading to the physical induration measured by the clinician.

• Dose-Response: There is a threshold effect; 0.1 mL is the standard dose required to elicit a response in a sensitized individual. Increasing the dose further primarily increases the risk of local tissue damage rather than diagnostic accuracy.
• Time to Onset: The reaction is 'delayed.' It is rarely visible before 24 hours.
• Peak Effect: The maximum induration typically occurs between 48 and 72 hours.
• Duration: The localized bump usually persists for 4-7 days before being reabsorbed by the lymphatic system.

| Parameter | Value |

|---|---|

| Bioavailability | Negligible (Intradermal) |

| Protein Binding | N/A (Local Action) |

| Half-life | N/A (Biologically degraded at site) |

| Tmax | 48-72 hours (for physical response) |

| Metabolism | Proteolytic degradation by local macrophages |

| Excretion | Lymphatic clearance of fragments |

• Composition: A sterile solution containing the water-soluble antigens of Candida albicans. It contains proteins, polysaccharides, and glycopeptides.
• Molecular Weight: Variable (complex mixture of fungal proteins).
• Solubility: Soluble in aqueous buffered solutions.
• Preservatives: Often contains phenol (0.4%) to maintain sterility and stability.

Candida Albicans is classified as a Non-Standardized Fungal Allergenic Extract. It is part of a group of diagnostic antigens that includes Mumps Skin Test Antigen and Tuberculin Purified Protein Derivative (PPD). Within the EPC (Established Pharmacologic Class) system, it is recognized for its role in identifying immune system status.