Water for injection

Approved Indications:

• Solvent and diluent for parenteral preparations:
  Used to reconstitute or dilute drugs intended for intravenous (IV), intramuscular (IM), subcutaneous (SC), or intradermal administration.
• Vehicle for parenteral solution preparation:
  Employed in the manufacture or compounding of sterile, nonpyrogenic injectable solutions when combined with suitable solutes.
• Irrigation (when explicitly labeled):
  May be used to moisten surgical dressings, tissue, or instruments during procedures.

Important Clinical Notes:

• Not for direct IV administration alone. Water for Injection is hypotonic, and direct injection can result in hemolysis.
• Must always be used after mixing with appropriate solutes or drugs to make the solution isotonic.

Route:

• Parenteral (via IV, IM, SC, intradermal routes) only after reconstitution with an active pharmaceutical agent or solute.

Dosage:

• Adults and Pediatrics:
  The volume of Water for Injection used depends on the specific drug being diluted or reconstituted, its required concentration, and the route of administration.
• Elderly:
  No specific dose adjustment required; however, attention to fluid volume is critical in patients with reduced renal or cardiac function.
• Special Populations:
• Renal impairment: Use cautiously to avoid fluid overload.
• Hepatic impairment: No specific adjustment, but caution advised when fluid balance is compromised.

Administration Instructions:

• Use only sterile technique during handling.
• Inspect for particulates or discoloration before use.
• Single-use containers should be used immediately after opening and any unused portion discarded.
• Only use WFI for reconstitution of drugs that are approved for parenteral use.

Water for Injection has no intrinsic pharmacologic activity. It serves as a sterile, pyrogen-free vehicle or diluent for preparing injectable drug formulations. By hydrating and dissolving solutes, WFI allows accurate dosing and safe parenteral delivery. It supports drug bioavailability and tissue compatibility when used to prepare isotonic or appropriately concentrated solutions. The therapeutic action is entirely dependent on the active medication it is used to reconstitute.

Water for Injection does not exhibit pharmacokinetics by itself. However, once administered in combination with an active drug:

• Absorption: Immediate with IV; variable with IM or SC routes based on drug properties.
• Distribution: Water disperses throughout total body water compartments.
• Metabolism: Not metabolized.
• Excretion: Eliminated unchanged via renal excretion.
• Onset/Duration: Determined by the active pharmaceutical ingredient used with WFI.

Pregnancy:

• FDA Category – Not Assigned (Excipient)
• Water for Injection is considered safe during pregnancy when used solely as a vehicle for approved medications. It does not cross the placenta or cause fetal harm.

Lactation:

• Water for Injection is safe during breastfeeding. It is not excreted into breast milk and poses no known risk to nursing infants. Caution applies only to the drug administered with WFI.

• Primary Therapeutic Class: Pharmaceutical Aid (Parenteral Diluent)
• Subclass: Sterile Nonpyrogenic Water (Excipient Class)
• Type: Non-active ingredient used in injectable drug formulation

• Direct intravenous injection without solutes (risk of hemolysis due to hypotonicity)
• Use with incompatible or unstable drugs
• Known hypersensitivity to the container materials (e.g., latex or plastic components, if applicable)
• Use in large volumes in patients with renal, cardiac, or hepatic failure without fluid monitoring

• Never inject WFI directly without additives, due to severe risk of hemolysis.
• Single-dose containers lack preservatives — discard any unused portion immediately.
• Use with caution in:
• Patients with renal impairment, congestive heart failure, or pulmonary edema
• Neonates and critically ill patients, where fluid volume must be strictly controlled
• Monitoring Required:
• Clinical assessment of fluid and electrolyte status is essential if large volumes are used.
• Monitor for signs of fluid overload, especially in high-risk patients.
• Handling Precautions:
• Maintain aseptic conditions.
• Ensure compatibility with intended drugs.

When used appropriately as a diluent, Water for Injection causes no direct side effects. However, improper use can result in adverse reactions:

Local Effects (at injection site):

• Pain or irritation (related to the drug, not WFI itself)

Systemic Effects (from incorrect use):

• Hemolysis from hypotonic injection
• Fluid overload or electrolyte imbalance (especially in patients with impaired renal/cardiac function)
• Febrile reaction or infection if sterility is compromised

Rare:

• Hypersensitivity or reaction to packaging materials
• Contamination-related complications (pyrogenic reaction)

• No pharmacologic drug interactions known for WFI itself.
• However:
• Compatibility issues may arise with certain drugs.
• Stability of active ingredients may vary in aqueous solution.
• pH and ionic strength may affect solubility or precipitation of reconstituted drugs.

Important Note: Always consult specific drug labeling or compatibility data before mixing with WFI.

• No recent safety warnings or indication changes directly related to WFI.
• Reinforced by USP and FDA guidelines to:
• Avoid direct injection of hypotonic water
• Use only in combination with appropriate sterile solutes
• Maintain aseptic preparation standards in clinical and manufacturing settings
• EMA and WHO emphasize strict sterility and handling protocols to prevent contamination and ensure patient safety in all injectable formulations.

• Temperature: Store at 20°C to 25°C (68°F to 77°F)
• Permitted Excursions: 15°C to 30°C (59°F to 86°F)
• Light Protection: Store in original packaging; protect from excessive light exposure
• Humidity: Protect from moisture and contamination
• Handling:
• Use aseptic technique during withdrawal and reconstitution
• Discard any unused portion of single-use vials immediately
• Refrigeration: Not required
• Do Not Freeze