8. UNIT 7_OBS & GYN DRUGS_T...,.K-1.pptx

Obstetrics drugs

1. UNIT 7 Drugs used in Obstetrics & Gynaecology 2/24/2024

2. INTRODUCTION Obstetrics is a science dealing with care of a pregnant woman during antenatal, and puerperal stages. Care of a pregnant woman is almost impossible without some form of pharmacological intervention. During pregnancy some drugs cross the placenta and can harm the fetus . 2/24/2024

3. SPECIFIC OBJECTIVES At the end of the lecture student nurses should be able to describe: Oxytocic and Prostaglandins (Uterine contraction) Sedative Drugs Analgesic Drugs 2/24/2024

4. Oxytocic and Prostaglandins Drugs 2/24/2024

5. OXYTOCICS Oxytocic drugs are used to: I nduce abortion Augment labour / Induce labour Management of incomplete abortion P revent post partum haemorrhage in the third stage of labour. 2/24/2024

6. OXYTOCIC DRUGS CONT’D These drugs include Oxytocin, Ergometrine, Ergometrine + Oxytocin (Syntometrine) Prostaglandins. 2/24/2024

7. Oxytocin ( S yntocinon) Presentation: Injection containing 5 units, 10 units per ml of oxytocin Indications : Induction or augmentation of labour, management of third stage of labour. Dose : Induction of labour; 10 units in one liter of 5% dextrose solution or Normal saline by IV infusion. Initially 5 drops /minute then increase the rate by 5 drops every 30 minutes until efficient contractions are obtained (over 10 minutes 3 contraction lasting 40 seconds). Do no not exceed 60 drops/minute. Management of third Stage;10 units. Control of post-partum hemorrhage: 20 units in 5% dextrose by IV. 2/24/2024

8. Oxytocin (Syntocinon ) cont’d Side effects: Hyperstimulation leading to uterine rupture and foetal asphyxia, maternal hypertension and sub arachnoid hemorrhage, intoxication. Caution : previous caesarean section, concomitant use with prostaglandins. Contra-indications: foetal distress, placenta praevia . Obstruction: d o not give in Cephalopelvic disproportion (CPD ), D o not give in a hypertensive 2/24/2024

9. Ergometrine Maleate Presentation : Injection containing 500mcg ergometrine maleate; tablets containing 250mcg, 500mcg Ergometrine maleate. Indications : Incomplete abortion; management of third stage of labour, post partum haemorrhage. Dose : Oral; 500mcg – 1mg, intramuscular injection; 200 – 500mcg, intravenous injection; 100 – 500mcg. Side effects: Nausea, vomiting and transient increase in blood pressure Caution : renal impairment , multiple pregnancy. Contra-indications : Severe hypertension , cardiac disease, eclampsia 2/24/2024

10. Ergometrine + Oxytocin (Syntometrine) Presentation : Injection containing Ergometrine maleate 500mcg + oxytocin 5 units/ml ampoule Indications : Management of third stage of labour, incomplete abortion to prevent haemorrhage Dose : 1ml, intramuscular for incomplete abortion and management of third stage of labour Side effects: Vomiting, nausea and hypertension. Contra-indications : Severe heart disease, severe hypertension. 2/24/2024

11. Prostaglandins These are used to induce abortion or augment labour as well as to minimize blood loss from the placenta. Examples of prostaglandins include; Gemeprost, Misoprostol, Dinoprostone Carboprost, 2/24/2024

12. Gemeprost Presentation: pessaries containing 1mg Gemeprost. I ndications: induction of abortion, cervical ripening for induction of labour in intra uterine foetal death. Dose: 1mg vaginal pessary inserted in posterior fornix 3 hours before surgery to maximum of 5mg. Side effects: nausea, vomiting, diarrhoea, flushing, muscle weakness, dyspnoea, chest pain, mild pyrexia, uterine rupture. Caution: obstructive airway disease, cardio vascular insufficiency, raised intraocular pressure 2/24/2024

13. Misoprostol (Cytotec) Presentation: Pessaries containing 3mg, tablet containing 500mcg Indication: induction of abortion, cervical ripening for induction of labour in intra uterine foetal death. Dose: 1mg vaginal pessaries inserted in posterior fornix every 6hours to maximum of 6mg, oral 500mcg every hour Side effects: Nausea, vomiting, diarrhoea, muscle weakness, dyspnoea, chest pain, uterine rupture, mild pyrexia, abruptio placenta, still birth. Contraindication : Placenta praevia, Cephalopelvic disproportion (CPD), and Foetal distress. 2/24/2024

14. Dinoprostone : Presentation: Pessaries containing 3mg Dinoprostone, Tablets containing 500mcg Dinoprostone. Indications : Induction and augmentation of labour Dose : By vaginal induction of labour insert pessary high into posterior fornix 3mg followed by 3mgs after 6 hours to maximum 6 mg. Oral; 500mcg followed by 0.5 – 1 mg (1.5mg maximum) at hourly intervals. Side effects: Nausea, vomiting, diarrhea , muscle weakness, dyspnoea, chest pain, mild pyrexia, uterine rupture , abruptio placenta, fever. 2/24/2024

15. Dinoprostone cont’d: Caution: Same as cytotec Contra-indications : Same as cytotec 2/24/2024

16. Alkalinizing Agents These are drugs used to prevent premature labour in women of 24 -33 weeks gestation. The administration of these drugs is seen useful in postponing labour long enough to allow ; Transfer patient for specialist treatment for operative delivery if emergencies arise such as cord prolapse and breach presentation Administration of corticosteroids to hasten fetal lung maturation 2/24/2024

17. The goal for these drugs is to reduce uterine contractions and arrest cervical dilation using the lowest effective dose of this same drugs Alkalinizing Agents are also called Myometrial relaxants 2/24/2024

18. Myometrial relaxants These drugs include Beta2 adregenoreceptor agonist such as; Salbutamol Magnesium Sulphate 2/24/2024

19. Salbutamol Presentation : Tablets containing 2mg, 4mg salbutamol sulphate. Intravenous infusion containing 1mg/ml salbutamol as sulphate Indications : uncomplicated premature labour, foetal asphyxia due to hypertonic uterine action. Dose : Intravenous infusion premature labour starting with 50mcg/minute gradually increase to 150 –350mcg/minute and continue for 12 – 24 hours after contractions have stopped. Oral; 4mg every 6 – 8 hours 2/24/2024

20. Salbutamol cont’d Side effects: Nausea, vomiting, flushing, sweating, tremor , tachycardia Contra-indications : not for use in 1st and 2nd trimesters (not effective). 2/24/2024

21. Magnesium Sulphate Presentation : Injection containing 50% (5g) ampoule. Indications : Fulminant pre-eclampsia, Eclampsia. Dose : loading Dose of 14g. I V administration; 4g(20%) intravenous. slowly over 5 -20minutes then 10mg(50%) (5g in each buttock). Total loading dose 14g. Maintenance dose : 5g magnesium sulphate in alternate buttock every 4 hours. A total of six maintenance doses are recommended. 2/24/2024

22. Magnesium Sulphate cont’d Side effects: Hypermagnesaemia, nausea, hypotension, arrhythmias, coma, respiratory depression, loss of tendon reflexes, muscle weakness, drowsiness, confusion. Caution: Vital signs and magnesium sulphate blood levels must be closely monitored. Antidote: 10mls of 10% calcium gluconate intravenous slowly to manage the toxicity 2/24/2024

23. Nursing Considerations : MgSO4 Assess patient’s deep tendon reflex Do lung function test to assess patients breathing patterns. Observe for respiratory depression which is a side effect of MgSO4 Give an antidote: Calcium gluconate for severe side effects to replace calcium. Give with caution in pregnant mother with cardiac conditions Discontinue therapy if pulmonary oedema occurs and initiate a diuretic therapy.eg Lasix 2/24/2024

24. SEDATIVES 2/24/2024

25. Sedatives Sedatives are used to produce relaxation, drowsiness and sleepiness, hence these drugs are useful in labour to settle the patients. The drugs are also important during labour because of their calming effects and because they counteract the emetic effects of labour itself. The most commonly used drugs are as follows: 2/24/2024

26. Promethazine(Phenergan ) Presentation: 12.5mg , 25mg, 50mg tabs 25mg and 50mg/ml Dose: In early stages of labour 25-50mg im or iv, then 25-75mg after labour or prn maximum dose of 100mg per day. Side Effects: Dizziness , sleepiness, confusion, disorientation, drowsiness, blurred vision, nausea, vomiting, dry mouth. Contraindication: Hypersensitivity, intestinal obstruction 2/24/2024

27. Chlorpromazine (Largactil ) Presentation: 25mg/ml injection,10mg, 25mg, 50mg and 100mg tablets Dose : 10-25mg prn Side Effect: Nasal congestion, dysuria, blurred vision, dizziness, sleepiness, confusion, disorientation, drowsiness, nausea, vomiting, tachycardia Contraindication: Hypersensitivity and Intestinal obstruction 2/24/2024

28. Diazepam (Valium) Presentation : 5mg/ml injection, 2mg, 5mg and 10mg tablets Dose : 2-10mg prn Side Effects : Drowsiness, headache, fatigue, hallucinations, blurred vision, insomnia, tremor, transient amnesia. Contraindications : Glaucoma, Hypersensitivity and Alcohol intoxication 2/24/2024

29. Analgesic Drugs 2/24/2024

30. ANALGESICS Analgesics are used for relief of pain during labour. Nevertheless, it is recognized that women’s need for relief of pain varies as some women do not need pain relief during labour. Some of the analgesics used in labour are as follows: Pethedine Morphine Diclofenac Ibuprofen Paracetamol 2/24/2024

31. Pethidine This is a controlled drug and mostly administered to mothers who have given birth through caesarean section, reason being that they experience severe pain Mode of Action : action is thought to be via the opiate receptors , altering the patients perception of pain . Indication : It is particularly useful in severe , acute or severe chronic pain. Presentation :10mg , 25mg, 50mg, 75mg and 100mg/ml injection, 50mg and 25mg tablets 2/24/2024

32. Pethidine Cont’d Dosage : 50-100mg intramuscular, frequency it is given in three doses, when one is just from operating theatre, another after 8 hours and the last dose also after 8 hours Side-Effects : Nausea,vomiting,dizziness,drowsiness,weakness,hallucinations,dry mouth , palpitations and respiratory depression. Contraindications : Acute asthma, head injury, increased intracranial pressure , seizures, renal or hepatic diseases . 2/24/2024

33. Morphine Mode of Action : As for Pethidine Presentation : 10mg, 15mg, 20mg and 30mg/ml injection, 10mg, 15mg and 30mg tablets. Dosage: 10mg subcutaneously or IM, 10-30mg PO 10-20mg P.R.N, Doses to be repeated only after four hours. Side Effects: As for Pethidine Contraindications: As for Pethidine 2/24/2024

34. Diclofenac Mode of Action : It relieves pain by inhibiting prostaglandins to secret histamines which induces inflammation. Presentation : Tablets 25mg, 50mg, Injection ampules 75mg. Dose: 50mg tds x 3/7 tabs, 75mg tds x 3/7 im Side Effects: Headache , dizziness, nervousness, peripheral oedema, fluid retention, peptic ulceration, constipation and acute renal failure. Contraindications : Hypersensitivity, Impaired renal and hepatic function and Peptic ulcer disease 2/24/2024

35. Ibuprofen Mode of Action : As for Diclofenac Presentation : 200mg tablets Dosage: 400mg prn not exceed 1200mg per day less than three days. Side Effects: As for Diclofenac Contraindications: As for Diclofenac 2/24/2024

36. Other Uterine Relaxants Salbutamol Nifedipine Aspirin Indomethacin Indication : - Dysmenorrhea Threatening abortion Premature labour Contraction ring during labour. 2/24/2024

37. REFERENCES Sue Jordan, (2002), PHARMACOLOGY FOR MIDWIVES, Creative, Print and Design, Britain. Linda. J, (1998), NURSE PRACTIONER’S DRUG HANDBOOK, 2nd Edition, Spring House Corporation, USA. 2/24/2024

38. END OF PRESENTATION 2/24/2024