How to give azithromycin to a rat? - briefly
Administer azithromycin to a rat by oral gavage using a calibrated syringe with a flexible feeding needle, diluting the drug in sterile water and dosing according to body weight (e.g., 10 mg/kg). Observe the animal for 24 hours, noting any adverse reactions or signs of distress.
How to give azithromycin to a rat? - in detail
Azithromycin administration to a laboratory rat requires precise dose calculation, sterile preparation, and appropriate delivery method. The following steps outline a complete protocol.
Calculate the dose.
- Determine the intended therapeutic dose in milligrams per kilogram (mg/kg). Common experimental regimens range from 10 mg/kg to 30 mg/kg.
- Weigh the animal on a calibrated scale; record the mass to the nearest gram.
- Multiply the dose (mg/kg) by the animal’s weight (kg) to obtain the required amount of drug (mg).
Prepare the suspension.
- Use pharmaceutical‑grade azithromycin powder.
- Dissolve the calculated amount in sterile physiological saline (0.9 % NaCl) or sterile water for injection.
- Adjust the final volume so that the concentration allows delivery of the full dose in a volume not exceeding 0.2 mL per 100 g body weight, minimizing gastric irritation.
- Vortex briefly; if any particles remain, filter through a 0.22 µm sterile syringe filter.
Select the route.
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Oral gavage (preferred for precise dosing).
- Equip a stainless‑steel gavage needle sized for the rat’s body weight (e.g., 20 G, 1.5 in).
- Restrain the animal gently, tilt the head upward, and insert the needle along the esophageal axis, avoiding the trachea.
- Deliver the calculated volume slowly (≈1 mL/30 s).
- Observe the animal for signs of regurgitation; if observed, repeat the procedure with a new needle.
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Mixed in feed or drinking water (suitable for chronic administration).
- Incorporate the drug into a known quantity of chow or water to achieve the target mg/kg/day based on average daily intake.
- Verify homogeneity by sampling the mixture and measuring concentration with spectrophotometry or HPLC.
- Record actual consumption daily to adjust concentrations as needed.
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Subcutaneous injection (alternative when oral route is contraindicated).
- Use a sterile 26‑30 G needle and inject the prepared solution into the dorsal scapular region.
- Limit the injection volume to ≤0.5 mL per 100 g to prevent tissue damage.
Safety and monitoring.
- Wear gloves, lab coat, and eye protection throughout preparation and administration.
- Dispose of sharps in designated containers.
- After dosing, monitor the rat for at least 30 minutes for adverse reactions: lethargy, respiratory distress, or abnormal posture.
- Record body weight, food and water intake, and clinical observations daily for the duration of treatment.
Documentation.
- Log the batch number of azithromycin, preparation date, concentration, administered volume, and individual animal identifiers.
- Maintain a temperature‑controlled storage record for the drug stock (2‑8 °C, protected from light).
Following these procedures ensures accurate, reproducible delivery of azithromycin to a rat while minimizing stress and potential complications.