What to do if I have a rash on my face with fever?

Facial Rash with Fever: Immediate Assessment and Management

If you have a facial rash with fever, seek immediate medical evaluation to rule out life-threatening infections like meningococcemia or Rocky Mountain Spotted Fever, though viral exanthems and drug reactions are more common causes. 1, 2

Critical Red Flags Requiring Emergency Evaluation

You need urgent assessment if ANY of these are present:

• Non-blanching petechial or purpuric rash (doesn't fade when pressed) with high fever and severe headache—this suggests meningococcemia, which can progress to life-threatening purpura fulminans within hours 3
• Rash involving palms and soles with fever, headache, and recent tick exposure or travel to endemic areas—this pattern suggests advanced Rocky Mountain Spotted Fever with 5-10% mortality risk 1, 4
• Altered mental status, severe headache, or neck stiffness accompanying the rash and fever—these indicate possible meningoencephalitis 1
• Rapid progression of rash from blanching macules to petechiae over 24-48 hours 1

Most Likely Diagnoses Based on Rash Characteristics

If Rash SPARES the Face (Trunk and Extremities Only)

Viral exanthems are the most common cause, particularly enteroviral infections that characteristically spare the palms, soles, face, and scalp 2, 4. These include:

• Human herpesvirus 6 (roseola)—macular rash appearing after high fever resolves 4
• Parvovirus B19—"slapped cheek" appearance initially, though this involves the face 4
• Epstein-Barr virus—especially if you recently took ampicillin or amoxicillin 2, 4

If Rash INVOLVES the Face

Rocky Mountain Spotted Fever typically spares the face, making this diagnosis less likely if facial involvement is prominent 1. However, critical exceptions exist:

• RMSF rash appears 2-4 days after fever onset as small blanching pink macules on ankles, wrists, or forearms, evolving to maculopapular lesions that spread centrally but usually spare the face 1, 4
• Up to 20% of RMSF cases never develop rash, and absence of rash is associated with increased mortality 4, 3
• Less than 50% have rash in the first 3 days of illness 4

Human Monocytic Ehrlichiosis can involve the face but occurs in only 30% of adults, appearing later (median 5 days after fever onset) with variable patterns from petechial to diffuse erythema 1, 4

Drug Hypersensitivity Reactions

Query about ANY new medications in the past 2-3 weeks, particularly antibiotics, NSAIDs, or anticonvulsants 2. Drug eruptions present as:

• Fine reticular maculopapular rashes or broad flat erythematous macules and patches 2, 4
• Can include petechial components 2
• Up to 40% of patients may not recall or report new medications, making this a commonly missed diagnosis 2
• Prominent itchiness with sparing of palms and soles in the absence of fever favors drug reaction over infection 2

Immediate Diagnostic Workup Required

Do not wait for laboratory confirmation if tickborne rickettsial disease is suspected—initiate treatment immediately 4. However, obtain:

• Complete blood count with differential—looking for leukopenia and thrombocytopenia, which are critical red flags for RMSF/ehrlichiosis 1, 4
• Comprehensive metabolic panel—hyponatremia and elevated hepatic transaminases suggest rickettsial disease 1, 4
• Acute serology for Rickettsia rickettsii, Ehrlichia chaffeensis, and Anaplasma phagocytophilum if tick exposure or endemic area travel 4
• Peripheral blood smear if thrombocytopenia present to differentiate causes 2

Treatment Decisions

If Tickborne Rickettsial Disease Suspected

The CDC recommends initiating doxycycline 100 mg twice daily immediately if fever + rash + headache + tick exposure or endemic area exposure are present, without waiting for laboratory confirmation 4.

• Clinical improvement expected within 24-48 hours of starting doxycycline 4
• Severe complications (meningoencephalitis, ARDS, multiorgan failure) occur with delayed treatment 4

If Drug Reaction Suspected

Discontinue the offending agent immediately and provide symptomatic treatment with antihistamines for pruritus 2. Prednisone may be considered but carries risk if infection is present 5.

If Viral Exanthem Suspected

Supportive care with antihistamines for pruritus and monitoring for development of classic viral syndrome features 2. The absence of fever does not exclude viral exanthems, as fever may have resolved or been mild 2.

Critical Pitfalls to Avoid

• Do not wait for the classic triad of fever, rash, and tick bite in RMSF—it is present in only a minority at initial presentation 3
• In darker-skinned patients, petechial rashes may be difficult to recognize, increasing risk of delayed diagnosis 2, 3
• Rash on palms and soles is not pathognomonic for any single condition—consider RMSF, meningococcemia, secondary syphilis, endocarditis, and drug reactions 1, 3
• Absence of rash does not exclude serious disease—up to 20% of RMSF cases and 50% of early meningococcal cases lack rash 3

Red Flags Requiring Immediate Re-evaluation

Return for urgent assessment if you develop:

• Fever (if initially afebrile) or worsening fever despite treatment 2
• Progression of petechiae to purpura or ecchymoses 2
• Development of systemic symptoms (confusion, severe headache, difficulty breathing) 2
• Involvement of palms and soles 2