L612 Pill Identification
The tablet imprinted with L612 is an over the counter (OTC) antihistamine. It is a generic formulation equivalent to brand-name Claritin (10 mg) or Vicks QlearQuil 24 Hour Allergy Relief.
Attribute Specification
- Active Ingredient – Loratadine (10 mg)
- Appearance – White, oval tablet
- Imprint – “L612” on one side, plain on the reverse
- Manufacturer / Distributor – LNK International, Inc. (commonly distributed under store-brand labels like Target, Kroger, Walgreens, or Vicks)
- Drug Class – Second-Generation Antihistamine (H1 Receptor Antagonist)
- Legal Status – Over the Counter (OTC) / Non-controlled
Mechanism of Action
Loratadine provides targeted relief from allergic reactions by blocking histamine activity in the body:
- Selective Receptor Antagonism: Loratadine is a long-acting, tricyclic peripheral histamine receptor antagonist. During an allergic reaction, mast cells release histamine, which binds to receptors and causes classic allergy symptoms (sneezing, swelling, itching, and mucus production). Loratadine competitively inhibits histamine at these sites.
- Non-Sedating Profile: Unlike first-generation antihistamines (such as diphenhydramine/Benadryl), loratadine does not readily cross the blood-brain barrier. Because it acts primarily outside the central nervous system, it causes significantly less drowsiness.
- Active Metabolite: Loratadine is metabolized in the liver (via CYP3A4 and CYP2D6 enzymes) into its active metabolite, desloratadine, which extends its therapeutic effect over a 24-hour period.
Therapeutic Indications & Dosage
Standard Uses
Prescribed or used OTC for the temporary relief of symptoms caused by hay fever, seasonal allergies, or upper respiratory allergies:
- Sneezing
- Runny nose (rhinorrhea)
- Itchy, watery eyes
- Itching of the nose, throat, or skin (urticaria / hives)
Standard Dosage Guidance
- Adults and Children (Ages 6 and older): 10 mg (1 tablet) orally once daily. Do not exceed 10 mg (1 tablet) in a 24-hour period.
- Children under 6 years: Standard 10 mg film-coated tablets are not recommended. Liquid or chewable formulations are typically used for younger pediatric populations.
- Administration: Swallow whole with water. It may be taken with or without food.
Side Effects
Loratadine is generally well-tolerated, but some individuals may experience mild adverse effects.
Common Side Effects
- Mild headache
- Fatigue or feeling tired
- Dry mouth
- Somnolence (drowsiness) – rare at recommended doses, but can occur in sensitive individuals
Uncommon / Severe Side Effects (Consult a Doctor)
- Severe allergic reaction (anaphylaxis: rash, swelling of the face/throat, severe dizziness, difficulty breathing)
- Fast, pounding, or irregular heart rate (palpitations)
- Severe dizziness or feeling close to passing out
- Severe abdominal pain or jaundice (yellowing of eyes/skin, indicating potential liver stress)
Precautions & Warnings
- Dose Adjustments for Kidney or Liver Disease: Patients with pre-existing liver impairment or severe renal insufficiency process loratadine more slowly. A lower starting dose (e.g., 10 mg taken every other day) is typically recommended under medical supervision.
- Allergy Skin Testing: Antihistamines interfere with allergic skin tests. Loratadine should be discontinued at least 48 to 72 hours prior to any allergy skin testing to prevent false-negative results.
- Alcohol & Sedatives: Although non-drowsy for most people, taking loratadine with alcohol or central nervous system depressants can increase the risk of fatigue or lightheadedness.
- Pregnancy & Breastfeeding: Loratadine is considered low risk during pregnancy and lactation, but nursing mothers should consult a doctor as small amounts pass into breast milk.
- Overdose Risk: Overdosage (taking more than 10 mg in 24 hours) does not increase efficacy and significantly raises the likelihood of severe drowsiness, headache, and tachycardia (rapid heartbeat).