🇲🇾 NPRA — Bahagian Regulatori Farmasi Negara
Arahan Kerja · PKKK/300/UAT/037
Ujian Keseragaman Berat
Uniformity of Weight Test — Comprehensive Guide
Step-by-step procedure guide based on NPRA's official SOP for uniformity of weight testing of pharmaceutical products. Covering uncoated tablets, coated tablets, hard capsules, soft capsules, and lozenges per USP 43 <2091>.
📄 PKKK/300/UAT/037
📘 USP 43 <2091>
🏛️ PKKK/200/UAT/002
📋 Terbitan 3, Semakan 1
◈ 1. Tujuan (Purpose)
This work instruction (Arahan Kerja) serves as a translation of the Tatacara Pengujian Uniformity of Weight (Document No. PKKK/200/UAT/002). Where discrepancies exist between this work instruction and the test procedure, the test procedure shall be used as the primary reference.
💡 Key Objective: To determine whether traditional pharmaceutical products tested comply with the
prescribed uniformity of weight requirements.
◈ 2. Skop (Scope)
This work instruction applies to the uniformity of weight test for traditional pharmaceutical products in the following dosage forms:
Tablet
Kapsul (Capsule)
Lozenges
⚠️ Exclusion: This test is NOT applicable for products in pill (pil) and pastille (pastilles) dosage forms.
◈ 5. Tanggungjawab (Responsibilities)
5.1 Ketua Seksyen
- Review investigation reports for samples that fail the uniformity of weight test
- Endorse the decision for tests that do not pass
5.2 Ketua Unit / Responsible Officer
- Ensure this procedure is followed during uniformity of weight testing
- Review investigation reports for samples that fail
- Endorse pass/fail decisions
5.3 Pegawai Farmasi
- Supervise analyses conducted by Pegawai Farmasi and Penolong Pegawai Farmasi
- Review test reports
- Conduct investigations for out-of-specification samples and prepare reports for failed samples
5.4 Penolong Pegawai Farmasi U29
- Conduct the uniformity of weight test following the established procedure
- Prepare the test report
◈ 6. Prosedur (Procedure)
📋 Pre-Test Requirement: Before conducting this test, ensure a minimum of 20 tablets/capsules
are available for testing. If insufficient, the sample shall be reported as 'Lulus' (Pass) but with remarks
noting "Ujian keseragaman berat tidak dapat dijalankan kerana sampel yang diterima tidak mencukupi".
General Requirements
6.1
Ensure the balance used has an appropriate minimum weight capacity for weighing 1 unit of sample.
6.2
Use forceps when weighing the sample.
6.3
If the sample needs to be held by hand, use gloves.
6.4.1
Weigh each of 20 randomly selected tablets/lozenges individually.
6.4.2
Calculate the average weight and determine the acceptance limits (minimum and maximum) using the table and formula below.
USP 43 Acceptance Limits
| Average Weight | USP 43 Limit |
|---|---|
| < 0.130 g | Not more than 2 tablets exceed ±10% AND no tablet exceeds ±20% of average weight |
| 0.130 – 0.324 g | Not more than 2 tablets exceed ±7.5% AND no tablet exceeds ±15% of average weight |
| > 0.324 g | Not more than 2 tablets exceed ±5% AND no tablet exceeds ±10% of average weight |
📐 Limit Calculation Formula
Minimum limit (h%) = Average weight − (Average weight × h / 100)
Maximum limit (h%) = Average weight + (Average weight × h / 100)
Example (h = 10%):
Minimum = Average weight − (Average weight × 10/100)
Maximum = Average weight + (Average weight × 10/100)
Minimum = Average weight − (Average weight × 10/100)
Maximum = Average weight + (Average weight × 10/100)
6.4.3
Based on the limits obtained, calculate the minimum and maximum values as per the formula above.
6.4.4
Record the test decision in form PKKK/UAT/002A.
6.5.1
Weigh each of 20 randomly selected coated tablets.
6.5.2
Determine the acceptance limits using the table and formula in section 6.4.2 and 6.4.3.
6.5.3
Record the test decision in form PKKK/UAT/002A.
⚠️ If Failed: Place 20 tablets into a beaker filled with water at 37°C (use a dissolution apparatus to set the temperature).
6.5.4
If the test fails, place 20 tablets into a beaker with water at 37°C.
6.5.5
Stir the beaker gently for no more than 5 minutes. If the tablet coating has begun to dissolve, repeat this step for a shorter duration.
6.5.6
Dry the tablets at 50°C for 30 minutes in an oven.
6.5.7
Weigh each of the 20 dried tablets.
6.5.8
Determine the acceptance limits and calculate min/max as per sections 6.4.2 and 6.4.3.
6.5.9
Record the test decision in form PKKK/UAT/002A.
Stage 1 — Initial 20 Capsules
6.6.1
Weigh each of 20 randomly selected capsules.
6.6.2
Calculate the average weight. Acceptance limit: ±10% (as per section 6.4.3).
USP Limit: No capsule shall exceed ±10% of the average weight.
6.6.3
Record the test decision in form PKKK/UAT/002A.
If Failed — Content Weight Verification
6.6.4
If the test fails, repeat the test by re-weighing all capsules individually. Ensure each capsule identity is tracked.
6.6.5
Open each capsule, remove the contents, and clean the shell. Remove any adhering material from the shell.
6.6.6
Weigh each empty shell individually.
6.6.7
Calculate the content weight of each capsule: difference between the filled capsule weight and the empty shell weight.
6.6.8
Calculate the average content weight. Acceptance limit: ±10% and ±25% (as per section 6.4.3).
USP Limit: Not more than 2 capsules exceed ±10% AND no capsule exceeds ±25% of the average weight.
6.6.9
Record the test decision in form PKKK/UAT/002B.
Stage 2 — Additional 40 Capsules (if 3–6 fail ±10%)
6.6.10
If 3 to 6 capsules exceed ±10% and fall within the ±10–25% range, weigh an additional 40 capsules following steps 6.6.5–6.6.7.
6.6.11
Calculate the average content weight of all 60 capsules. Acceptance limit: ±10% and ±25% (as per section 6.4.3).
USP Limit: Not more than 6 capsules exceed ±10% AND no capsule exceeds ±25% of the average weight.
6.6.12
Record the test decision in form PKKK/UAT/002C.
Stage 1 — Initial 20 Capsules
6.7.1
Weigh each of 20 randomly selected soft capsules.
6.7.2
Calculate the average weight. Acceptance limit: ±10% (as per section 6.4.3).
USP Limit: No capsule shall exceed ±10% of the average weight.
6.7.3
Record the test decision in form PKKK/UAT/002A.
If Failed — Content Weight Verification
6.7.4
If the test fails, repeat by re-weighing all capsules individually. Ensure each capsule identity is tracked.
6.7.5
Inside a fume cupboard, cut each capsule open, remove the contents, and clean the shell with hexane solvent followed by acetone.
6.7.6
Allow the solvent to evaporate from the shells for no more than 30 minutes inside the fume cupboard.
6.7.7
Weigh each empty shell individually.
6.7.8
Calculate the content weight of each capsule: difference between the filled capsule weight and the empty shell weight.
6.7.9
Calculate the average content weight. Acceptance limit: ±10% and ±25% (as per section 6.4.3).
USP Limit: Not more than 2 capsules exceed ±10% AND no capsule exceeds ±25% of the average weight.
6.7.10
Record the test decision in form PKKK/UAT/002B.
Stage 2 — Additional 40 Capsules (if 3–6 fail ±10%)
6.7.11
If 3 to 6 capsules exceed ±10% and fall within the ±10–25% range, weigh an additional 40 capsules following steps 6.7.5–6.7.8.
6.7.12
Calculate the average content weight of all 60 capsules. Acceptance limit: ±10% and ±25% (as per section 6.4.3).
USP Limit: Not more than 6 capsules exceed ±10% AND no capsule exceeds ±25% of the average weight.
6.7.13
Record the test decision in form PKKK/UAT/002C.
◈ Decision Flow Summary
LULUS (Pass)
- Tablets: ≤2 units outside primary limit, none outside secondary limit
- Capsules (Stage 1): All within ±10%
- Capsules (Stage 2): ≤2 of 20 outside ±10%, none outside ±25%
- Capsules (Stage 3): ≤6 of 60 outside ±10%, none outside ±25%
TIDAK LULUS (Fail)
- Tablets: >2 units outside primary limit OR any unit outside secondary limit
- Capsules: Any unit exceeds ±25% OR >6 of 60 exceed ±10%
- Report investigation and provide laporan siasatan
◈ 7. Rekod Kualiti (Quality Records)
| No. | Quality Record | Form No. |
|---|---|---|
| 7.1 | Borang Ujian Keseragaman Berat | PKKK/UAT/002A |
| 7.2 | Borang Ujian Keseragaman Berat Kapsul (Isi Kapsul) — Peringkat Pertama | PKKK/UAT/002B |
| 7.3 | Borang Ujian Keseragaman Berat Kapsul (Isi Kapsul) — Peringkat Kedua | PKKK/UAT/002C |
◈ Rujukan (References)
USP 43 <2091>
Weight Variation in Dietary Supplements
PKKK/200/UAT/002
Tatacara Uniformity of Weight
◈ Sejarah Semakan (Revision History)
| Edition | Rev. | Date | Key Changes |
|---|---|---|---|
| 1 | 0 | 15 Nov 2016 | Initial release |
| 1 | 1 | 10 Jul 2017 | Updated by Nur Syazana Ahmad Nordin |
| 2 | 0 | 10 Feb 2020 | Updated effective date |
| 2 | 1 | 15 Dec 2020 | Updated responsibilities |
| 3 | 0 | 1 Sep 2023 | Updated document numbering to PKKK/300/UAT/037; reference to PKKK/200/UAT/002 |
| 3 | 1 | 15 Nov 2024 | Updated institution name; reference from USP 35 to USP 43; updated responsibilities |
🏛️ SISTEM KUALITI NPRA — APPROVED COPY