Amoxicillin Trihydrate

Product Story

Amoxicillin was synthesized in 1972 at Beecham Research Laboratories in the UK, building on the earlier success of ampicillin (1961). The team, led by researchers who had previously developed the first semi-synthetic penicillins, created amoxicillin by adding a hydroxyl group to ampicillin's phenyl side chain. This single structural change — which chemically distinguishes amoxicillin from its predecessor — dramatically improved oral absorption: from ~35% bioavailability for ampicillin to approximately 80-95% for amoxicillin. The compound was launched as Amoxil in 1974 and has since become one of the most prescribed antibiotics in global medical history.

Amoxicillin exerts its bactericidal effect by irreversibly binding to penicillin-binding proteins (PBPs) on the bacterial cell wall, specifically inhibiting transpeptidase enzymes that cross-link peptidoglycan strands during cell division. This leads to cell lysis and death. Its aminopenicillin structure extends the spectrum beyond penicillin G to include many Gram-negative organisms — notably E. coli, H. influenzae, and H. pylori — while retaining strong activity against streptococci and enterococci. The trihydrate form ensures crystalline stability, with three water molecules incorporated into the crystal lattice to prevent the hygroscopic degradation that plagues the anhydrous form.

Amoxicillin's clinical advantage over ampicillin is threefold: superior oral bioavailability enabling twice-daily (BID) dosing versus ampicillin's three-to-four-times daily regimen; higher and more sustained serum concentrations; and significantly fewer gastrointestinal side effects. This pharmacokinetic profile, combined with the addition of beta-lactamase inhibitors (clavulanic acid as co-amoxiclav), has made amoxicillin the backbone of first-line therapy for respiratory tract infections, urinary tract infections, and H. pylori eradication worldwide. The WHO lists amoxicillin on its Model List of Essential Medicines, and the co-amoxiclav combination is listed as an Access-group antibiotic.

As of mid-2026, global amoxicillin trihydrate API demand exceeds 25,000 metric tons annually, driven by high-volume manufacturing in India and China. China dominates the upstream intermediate supply chain (6-APA, produced from penicillin G via enzymatic cleavage) and accounts for the largest share of amoxicillin API production. Price volatility is closely linked to 6-APA feedstock costs and production capacity utilization in Shijiazhuang and Inner Mongolia. KingWish supplies GMP-certified amoxicillin trihydrate meeting BP/EP/USP/CEP/IN HOUSE standards, supporting pharmaceutical manufacturers worldwide with competitive lead times and full regulatory documentation.

Quality Specifications

Therapeutic Applications

• Respiratory tract infections: First-line oral therapy for community-acquired pneumonia, acute bronchitis, and sinusitis caused by S. pneumoniae and H. influenzae.
• Urinary tract infections: First-line treatment for uncomplicated UTIs caused by susceptible Enterobacteriaceae. BID dosing improves compliance over ampicillin.
• H. pylori eradication: Component of standard triple therapy (amoxicillin + clarithromycin + proton pump inhibitor) for 7-14 days. Amoxicillin resistance in H. pylori remains low compared to clarithromycin.
• Otitis media: Pediatric oral suspension for acute otitis media. High-dose regimen (80-90 mg/kg/day) recommended in regions with high penicillin-nonsusceptible pneumococcal rates.
• Dental infections: Prophylaxis and treatment of odontogenic infections; also used for infective endocarditis prophylaxis in at-risk patients per AHA guidelines.