Medical chemistry

Isotonicity

A solution is isotonic with plasma at ~0.9% NaCl (saline) or ~5% glucose. Plasma osmolarity ~285–295 mOsm/L.

Isotonic calculation

Sodium chloride equivalent (E): substance mass × E + NaCl = 0.9% equivalent. For a 1% drug with E=0.2: add 0.7% NaCl.

Percentage solutions

% mass/volume: 1% = 1 g per 100 ml. Dilution C1V1=C2V2. Chlorhexidine 0.05% from 20% concentrate — 1:400.

Buffers & pH

Eye drops — pH 6.5–8.5, active stability — in narrow ranges. Phosphate buffer is the standard for solutions.

Reconstitution

Antibiotics/peptides from powder: solvent volume → mg/ml concentration. Reconstituted storage — per instructions, usually fridge, days.

DIY limits

Sterile preparations aren't made at home — sepsis risk. Isotonic rinses/washes — yes; injections — only ready-made drugs.

Reference material for understanding pharmaceutical chemistry. Not instructions for compounding — dosing and sterility are a doctor's/pharmacist's job.

About Medical chemistry

Medical chemistry — isotonic solutions, percentages, buffers, reconstitution. Chemistry & Lab: Molar mass, dilution, pH, gases, safety. Use our tools without registration or installing software. All calculations happen in your browser — your data is never sent to a server.