What injection can be used to treat itching?

Injectable Treatments for Itching

For severe, refractory itching that has failed topical and oral therapies, intramuscular triamcinolone acetonide (40-80 mg IM) is the primary injectable corticosteroid option indicated for severe allergic conditions including contact dermatitis and atopic dermatitis when oral therapy is not feasible. 1

When Injectable Therapy Is Indicated

Injectable treatment for itching should be reserved for specific clinical scenarios:

• Grade ≥3 pruritus (constant itching limiting self-care or sleep) that has failed topical steroids and oral antihistamines 2
• Severe allergic conditions including contact dermatitis and atopic dermatitis where oral therapy is not feasible 1
• Incurable lymphoma-associated pruritus where oral corticosteroids may provide relief 2
• Anaphylaxis with severe itching requires epinephrine autoinjector (0.3 mg IM) as primary treatment 2

Specific Injectable Options

Intramuscular Corticosteroids

• Triamcinolone acetonide 40-80 mg IM is FDA-approved for severe allergic dermatologic conditions including contact dermatitis, atopic dermatitis, and bullous dermatitis herpetiformis when oral therapy is not feasible 1
• This should only be used after failure of topical moderate/high-potency steroids and oral antihistamines 2

Epinephrine (For Anaphylaxis Only)

• Epinephrine 0.3 mg IM autoinjector is indicated specifically for anaphylaxis-related itching (e.g., from bee/wasp stings), not for routine pruritus management 2
• Should be administered at first sign of anaphylaxis with tongue/throat swelling, difficulty breathing, or disseminated hives 2

Treatment Algorithm Before Considering Injections

You must exhaust this stepwise approach before injectable therapy:

1. First-line (Topical): Moderate/high-potency topical steroids (mometasone furoate 0.1% or betamethasone valerate 0.1% ointment) applied to affected areas 2, 3

2. Second-line (Oral antihistamines): Non-sedating H1 antihistamines like loratadine 10 mg daily or fexofenadine 180 mg daily 2, 3

3. Third-line (Neuromodulators): Gabapentin 900-3600 mg daily or pregabalin 25-150 mg daily for patients failing antihistamines 2, 3

4. Fourth-line (Antidepressants): Paroxetine, mirtazapine, or other antidepressants as alternatives 2, 3

5. Only then consider: Systemic/injectable corticosteroids for severe refractory cases 2, 1

Critical Caveats

• Injectable corticosteroids are NOT first-line therapy for routine itching—they carry significant systemic side effects and should be reserved for severe, refractory cases 2, 1
• Antihistamines have limited efficacy in non-histamine-mediated itch (like atopic dermatitis), despite widespread use 4, 5
• Reassess after 2 weeks of any treatment tier; if no improvement or worsening, escalate to next level 2
• For cancer therapy-related pruritus: If grade ≥3, interrupt the causative drug until symptoms resolve to grade 0-1, and consider discontinuation if no improvement after 2 weeks of treatment 2, 3
• Avoid escalating methylprednisolone above 2 mg/kg/day—there is no benefit to higher doses 2

Cause-Specific Injectable Considerations

• Hepatic pruritus: Rifampicin is first-line (not injectable steroids) 2, 3
• Uremic pruritus: Optimize dialysis parameters first; injectable steroids are not indicated 2, 3
• Lymphoma-associated pruritus: Oral corticosteroids may be used for incurable cases, but injectable forms are not specifically recommended 2