PIPERAZINE CITRATE
Clinical safety rating: caution
Comprehensive clinical and safety monograph for PIPERAZINE CITRATE (PIPERAZINE CITRATE).
Piperazine citrate acts as a gamma-aminobutyric acid (GABA) receptor agonist in nematodes, causing hyperpolarization of nerve membranes and flaccid paralysis of the worm, which is then expelled by normal peristalsis. It does not affect mammalian neuromuscular junctions due to differences in GABA receptor sensitivity.
| Metabolism | Piperazine is partially metabolized in the liver via N-methylation and oxidation. Approximately 20-40% of the dose is metabolized, with the remainder excreted unchanged in the urine. The metabolic pathways are not fully characterized, but CYP450 enzymes are minimally involved. |
| Excretion | Primarily renal (60-70% unchanged); biliary/fecal elimination accounts for 10-20% of the dose. |
| Half-life | Terminal elimination half-life: 2-4 hours in patients with normal renal function; may be prolonged in renal impairment. |
| Protein binding | Less than 10% bound to plasma proteins. |
| Volume of Distribution | Vd approximately 0.5-0.6 L/kg, indicating distribution mainly in extracellular fluid. |
| Bioavailability | Oral bioavailability is variable (30-60%) due to first-pass metabolism. |
| Onset of Action | Orally: Onset of anthelmintic effect within 2-4 hours after administration. |
| Duration of Action | Duration of action: Approximately 4-6 hours after a single oral dose; clinical efficacy for ascariasis may persist for 24-48 hours due to worm expulsion. |
| Molecular Weight | 143.2 |
| Action Class | Antiprotozoal agents |
| Brand Substitutes | Piperazine Citrate 750mg Syrup, Avizine Syrup, Antepar 750mg Syrup, Piperazine Citrate Syrup |
Adults: 3.5 g orally once daily for 2 days; may repeat after 1 week if needed.
| Dosage form | SYRUP |
| Renal impairment | GFR 10-50 mL/min: reduce dose by 50%; GFR <10 mL/min: contraindicated. |
| Liver impairment | Child-Pugh A: no adjustment; Child-Pugh B: reduce dose by 50%; Child-Pugh C: avoid use. |
| Pediatric use | Children 2-12 years: 75 mg/kg/day (max 3.5 g/day) orally once daily for 2 days. |
| Geriatric use | Use lowest effective dose; monitor for neurotoxicity and renal function; reduce dose if CrCl <50 mL/min. |
| 1st trimester | Piperazine is generally avoided during the first trimester due to limited safety data and potential teratogenic risk based on animal studies. Use only if clearly needed and no alternative. |
| 2nd trimester | Use with caution. No well-controlled studies in humans. Animal studies have shown adverse effects, but potential benefits may warrant use in some cases. |
| 3rd trimester | Use near term only if necessary. Theoretical risk of neonatal adverse effects such as muscle spasm or neurotoxicity. |
Clinical note
Comprehensive clinical and safety monograph for PIPERAZINE CITRATE (PIPERAZINE CITRATE).
| Placental transfer | Piperazine crosses the placenta (animal studies). Human data limited; transfer likely occurs. |
| Breastfeeding | Piperazine is excreted into breast milk in small amounts. Adverse effects in nursing infants have not been reported, but caution is advised due to potential neurotoxicity. Monitor infant for signs of muscle spasm or drowsiness. |
■ FDA Black Box Warning
None
| Serious Effects |
Hypersensitivity to piperazineRenal impairment (accumulation risk)Epilepsy or seizure disorders (may lower seizure threshold)Concomitant use with neurotoxic drugs
| Precautions | May cause neurotoxicity (e.g., dizziness, ataxia, seizures) especially in patients with renal impairment or pre-existing neurological disorders, Avoid use in patients with epilepsy or other seizure disorders, Use with caution in patients with hepatic or renal disease, May interfere with urine screening tests for catecholamines, causing false elevations, Concomitant use with pyrantel pamoate is contraindicated due to antagonistic effects |
| Food/Dietary | No significant food interactions. Take with food if gastrointestinal upset occurs. Avoid alcohol as it may increase central nervous system side effects. |
Loading safety data…
| Lactation Rating | L3 (Moderately Safe) |
| Teratogenic Risk | No adequate well-controlled studies in pregnant women. Animal studies not available. Potential risk unknown. Avoid use in first trimester unless benefits outweigh risks. |
| Fetal Monitoring | Monitor for maternal gastrointestinal disturbances, neurotoxicity; fetal monitoring not standard. |
| Fertility Effects | No known adverse effects on fertility in humans. |
| Clinical Pearls | Piperazine citrate causes paralysis of the worm musculature by blocking acetylcholine at the myoneural junction, leading to expulsion via peristalsis. It is primarily used for ascariasis and enterobiasis. Avoid in patients with epilepsy or renal impairment. Monitor for neurotoxicity (ataxia, confusion) especially in overdose. Can be given with a laxative to enhance worm expulsion. |
| Patient Advice | Take this medication exactly as prescribed, usually as a single dose or over 7 days. · You may pass worms in your stool; this is expected and indicates the drug is working. · Do not drive or operate heavy machinery if you experience dizziness or drowsiness. · Complete the full course even if you feel better to ensure all worms are eliminated. · Practice good hand hygiene and wash bedding in hot water to prevent reinfection. · Seek medical attention if you experience severe headache, vomiting, or vision problems. |