# Situation: A 34-year-old woman with a body mass index (BMI) of 42 kg/m², hypertension, and obstructive sleep apnea treated with continuous positive airway pressure (CPAP) undergoes laparoscopic Roux-en-Y gastric bypass. She has no diabetes. At discharge she is prescribed lifelong supplements, including calcium and iron. Which calcium instruction is correct for her?

> source: MyMerci (mymerci.kr)  
> url: https://mymerci.kr/pages/nclex_q.php?qn_id=630368  
> language: ko  
> subject: Nursing Practice IV — Care of Clients with Problems in Nutrition and Gastrointestinal, Metabolism and Endocrine, Perception and Coordination

## 문제

Situation: A 34-year-old woman with a body mass index (BMI) of 42 kg/m², hypertension, and obstructive sleep apnea treated with continuous positive airway pressure (CPAP) undergoes laparoscopic Roux-en-Y gastric bypass. She has no diabetes.

At discharge she is prescribed lifelong supplements, including calcium and iron. Which calcium instruction is correct for her?

## 보기

1. Calcium citrate in divided doses, taken apart from iron **✔ 정답**
2. Calcium carbonate in divided doses, taken apart from iron
3. Calcium citrate as a single daily dose, taken with iron
4. Calcium carbonate as a single daily dose, taken with iron

**정답: 1**

## 해설

Gastric bypass leaves a small pouch that makes little acid and bypasses the duodenum, where calcium is mainly absorbed. Calcium citrate does not need acid for absorption, so it is preferred, and it is taken in divided doses because only about 500 to 600 mg is absorbed at once. Calcium blocks iron absorption, so the two are taken at different times.

## 심화 해설

The correct calcium instruction
After Roux-en-Y gastric bypass, the client should take calcium citrate in divided doses, apart from iron. Each part of the instruction addresses a specific absorption problem created by the surgery or by the interaction between calcium and iron.

Why citrate rather than carbonate
The bypass creates a small gastric pouch that produces little acid and routes food past the duodenum and proximal jejunum, where calcium is mainly absorbed. Calcium carbonate needs stomach acid to dissolve and be absorbed, so it works poorly in this low-acid setting. Calcium citrate does not need acid for absorption, so it is preferred after bariatric surgery. These changes make lifelong supplementation necessary to protect bone health and prevent secondary hyperparathyroidism.

Why divided doses and separation from iron
The body can absorb only about 500 to 600 mg of calcium at one time. A single large daily dose is therefore poorly absorbed, and the rest is wasted. Splitting the total into two or three doses through the day improves the amount absorbed. Calcium blocks iron absorption, and both are needed after gastric bypass, which also raises the risk of iron deficiency anemia. Taking them at different times protects iron absorption.

| Option | Form | Dosing | Iron | Assessment |
| --- | --- | --- | --- | --- |
| 1 | Citrate | Divided | Apart | Correct |
| 2 | Carbonate | Divided | Apart | Carbonate needs acid the pouch lacks |
| 3 | Citrate | Single | With iron | Single dose poorly absorbed; blocks iron |
| 4 | Carbonate | Single | With iron | Three errors |

Other supplement teaching
Watch out! Clients sometimes stop supplements once they feel well; deficiencies after bypass may develop slowly and without early symptoms, so lifelong adherence and periodic laboratory monitoring are essential. The usual regimen also includes a multivitamin with minerals, vitamin B12 (because intrinsic factor and acid are reduced), and vitamin D. Chewable or liquid forms may be easier to tolerate in the early weeks.

Exam takeaway
Key point! After gastric bypass: calcium citrate, in divided doses of no more than about 500 to 600 mg, taken separately from iron. Carbonate needs acid; the bypassed stomach and duodenum cannot provide good conditions for it.

## 임상 시나리오

Calcium After Gastric BypassChoosing the form and timing of supplements
Use calcium citrate: it does not need acid, which the small bypass pouch lacks. Calcium is mainly absorbed in the bypassed duodenum.

Take it in divided doses, because only about 500 to 600 mg is absorbed at one time.

Take calcium and iron at different times, since calcium blocks iron absorption.

CautionSupplements are lifelong. Deficiencies of calcium, iron, vitamin B12, and vitamin D may develop silently, so periodic laboratory monitoring is needed.

## 핵심 개념

- **Roux-en-Y gastric bypass** — Bariatric surgery that creates a small gastric pouch connected directly to the jejunum.
- **Calcium citrate** — A calcium salt absorbed without stomach acid, preferred after gastric bypass.
- **Calcium carbonate** — A calcium salt that needs stomach acid for absorption.
- **Divided dosing** — Splitting a daily dose into smaller amounts to improve absorption.
- **Iron deficiency anemia** — Anemia from low iron stores, a common complication after gastric bypass.

## 같은 주제 문제

- [Situation: A 52-year-old man with alcohol use disorder is admitted for poor oral intake. H…](https://mymerci.kr/pages/nclex_q.php?qn_id=630266)
- [Situation: A 52-year-old man with alcohol use disorder is admitted for poor oral intake. H…](https://mymerci.kr/pages/nclex_q.php?qn_id=630267)
- [Situation: A 52-year-old man with alcohol use disorder is admitted for poor oral intake. H…](https://mymerci.kr/pages/nclex_q.php?qn_id=630268)
- [Situation: A 52-year-old man with alcohol use disorder is admitted for poor oral intake. H…](https://mymerci.kr/pages/nclex_q.php?qn_id=630269)
- [Situation: A 46-year-old woman has had heartburn and regurgitation after meals for 6 month…](https://mymerci.kr/pages/nclex_q.php?qn_id=630270)
- [Situation: A 46-year-old woman has had heartburn and regurgitation after meals for 6 month…](https://mymerci.kr/pages/nclex_q.php?qn_id=630271)
- [Situation: A 46-year-old woman has had heartburn and regurgitation after meals for 6 month…](https://mymerci.kr/pages/nclex_q.php?qn_id=630272)
- [Situation: A 38-year-old man comes to the outpatient clinic with epigastric pain for the p…](https://mymerci.kr/pages/nclex_q.php?qn_id=630273)

---

More free questions: [기출문제](https://mymerci.kr/)

_학습 참고용입니다. 실제 임상은 최신 지침과 소속 기관 프로토콜을 따르세요._