Golongan Cara Kerja Benefit Efek Samping Jenis Obat

Ca Ch Blocker Blocking transmembrane calcium transport Reduce intra-cellular calcium

- Per oral

- Low cost

- Minimum side effects

Constipation, diarrhea, dizziness or lightheadedness, Flushing, headache, nausea.

- Uncommon: vasodilation, drug induced hepatitis, fluid retention, hypocalcaemia, hypoglycaemia, hypotension, tachycardia, altered uteroplacental blood flow

Nifedipine

- Initial dose 20mg

- Followed by 3 doses: 20mg every 30 minutes if contractions continue

- Maintenance dose: 20-40mg orally four hourly for 48 hours

- Max dose 160mg/24 hours)

- Caution with doses > 60mg

-  After 72 hours, if maintenance is required, patients can be changed to long-acting nifedipine 30-60 mg daily

Anti-PG / NSAID Block the PG receptors - Per oral Concerns exist regarding premature ductal closure, oligohydramnios, necrotizing enterocolitis, and intraventricular hemorrhage when NSAIDs are administered during the third trimester

Indomethacin, celecoxib, sulindac, ketorolac, rofecoxib

- Indomethacin:

50 mg loading dose followed by 25–50 mg orally every 6 hours for up to 48 hours.

Oxytocin Receptor Blocker Memblokir reseptor oksitosin di uterus menurunkan kontraksi uterus

Given the lack of clear overall clinical benefit with atosiban, it is also considered reasonable not to use atosiban in clinical practice.

- Common: Headache, dizziness, vomiting, tachycardia, hypotension, hyperglycaemia

- Rare: PPH, serious allergic, fetal death in very premature infants

Atosiban

- Initial IV 6.75mg in 0.9 ml slowly injected over one minute

- A continuous infusion 24 ml/hr up to 3 hours

- A continuous infusion 8ml/hr up to 45 hours

MgSO4 Proposed mechanisms of action include competition with calcium at motor end plates and/or at plasma membrane voltage-gated channels

Because of its familiarity and presumed safety, magnesium sulfate has been a mainstay of tocolytic therapy since 1971

(http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3971910/)

Before 32 weeks’ gestation confers significant fetal neuroprotection. This has resulted in a reduced incidence and severity of cerebral palsy.

- Loading dose of 4–6 g in 10%–20% solution over 30 minutes

- Followed by a continuous infusion of 2 g per hour

- Titrated until a maximum of 4 g/hour is reached or until the patient has less than one contraction per 10 minutes

- Calcium gluconate should be readily available for reversal of any toxic side effects

Nitrate Advocated based on observations in animals that

Similar efficacy to ritodrine Transdermal nitroglycerine (a nitric oxide donor)

nitric oxide synthase activity was correlated with labor, but functional studies in humans were contradictory

Beta agonist Reduce the sensitivity to calcium & total intracellular calcium concentrations Myometrial relaxation

Compared to placebo, beta-agonists have been shown to reduce the incidence of delivery within 48 hours

Rarely used today due to their adverse side effect profile - palpitations, tremor, tachycardia, pulmonary oedema, myocardial ischaemia, and hyperglycaemia

Ritodrine, terbutaline, nylidrin, salbutamol, fenoterol, hexoprenaline, isoxsuprine

Isoxsuprine:

- 200-500 mcg / minute as IV infusion- Once labour has been arrested, administered

10 mg every 3-8 mg IM inj for several days- May continue prophilaxys orally: 30-90 mg

daily in divided doses