Pregnancy

When prescribing medications during pregnancy, it’s essential to consider both the safety of the mother and the developing fetus. The goal is to balance the need for treatment with the lowest possible risk. 

1. Nausea and Vomiting
   1. Doxylamine + Pyridoxine (Vitamin B6): A combination used for morning sickness, available as Diclegis or Pyridoxine (Vitamin B6) alone.
   2. Metoclopramide (e.g., Maxolon, Pramin): Can be used for more severe nausea and vomiting.
   3. Ondansetron (e.g., Zofran, Ondansetron Sandoz): Generally considered safe, though there is some debate about potential risks.
2. Pain and Fever
   1. Paracetamol (Panadol): The first-line painkiller in pregnancy.
3. Hypertension
   1. Methyldopa: Often the first choice for treating hypertension in pregnancy.
   2. Labetalol: Also commonly used.
   3. Nifedipine (e.g., Adalat, Nifedipine Sandoz): A calcium channel blocker, suitable for pregnancy.
4. Gestational Diabetes (GDM) and Pre-existing Diabetes
   1. Diet and Lifestyle Modification: The first step in managing GDM and pre-existing diabetes; involves dietary changes and increased physical activity. If diet and lifestyle modifications are insufficient to control blood glucose levels, pharmacotherapy is required 
   2. Insulin
      1. First-Line Treatment: Insulin is the first-line treatment for diabetes in pregnancy because it does not cross the placenta and has a long history of safe use.
   3. Oral Hypoglycemic Agents
      1. Metformin: Can be used in GDM and pre-existing type 2 diabetes; crosses the placenta but studies have shown it to be safe with no increase in congenital anomalies.
      2. Glibenclamide (Glyburide): Less commonly used; can be considered if insulin is not acceptable to the patient, but there are concerns about its transfer to the fetus and potential neonatal hypoglycemia.
5. Infections
   1. Penicillins (e.g., Amoxicillin, Amoxil): Generally considered safe.
   2. Cephalosporins (e.g., Cephalexin, Keflex): Also typically safe in pregnancy.
   3. Macrolides (e.g., Erythromycin, Roxithromycin): Usually safe, though there’s some concern with certain macrolides.
   4. Nitrofurantoin (e.g., Macrodantin): Can be used for urinary tract infections but avoid near term due to the risk of hemolytic anemia in the newborn.
6. Asthma
   1. Cat A – Salbutamol and Budesonide
   2. Cat B3 – Fluticasone, LABA
7. Depression and Anxiety
   1. Selective Serotonin Reuptake Inhibitors (SSRIs): Some SSRIs like Sertraline and Fluoxetine are considered relatively safe, but there are potential risks.
   2. Serotonin and Norepinephrine Reuptake Inhibitors (SNRIs): Some are used, but with caution.
   3. Tricyclic Antidepressants: Some are considered relatively safe.
8. Gastroesophageal Reflux Disease (GORD)
   1. Antacids (e.g., Mylanta, Tums): First-line for mild symptoms.
   2. H2 Blockers (e.g., Ranitidine, Famotidine): For more persistent symptoms.
   3. Proton Pump Inhibitors (e.g., Omeprazole, Pantoprazole): Used if H2 blockers are ineffective, though generally with caution.
9. Constipation
   1. Bulk-forming Laxatives (e.g., Psyllium, Metamucil): First choice.
   2. Stool Softeners (e.g., Coloxyl): Also considered safe.
10. Allergies
    1. Second Generation Antihistamines (e.g., Loratadine, Cetirizine): Preferred due to less drowsiness.
11. General Considerations
    1. Folic Acid Supplementation: Recommended for all pregnant women to prevent neural tube defects.
    2. Iron Supplements: Often necessary due to increased iron requirements.

Always evaluate the risk-benefit ratio before prescribing, and consult current guidelines or a specialist if unsure. It’s important to use the lowest effective dose for the shortest duration necessary. Pregnant patients should be monitored regularly for any adverse effects.

Drugs to Avoid

The quick answer is anything not on the list above shoud be avoided, however here are some common drugs and why they are avoided.

1. Anti-Emetics
   1. Prochlorperazine (Stemetil) is category C
2. Analgesics
   1. Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) – e.g., Ibuprofen, Aspirin, Naproxen: While low-dose aspirin may be prescribed under specific medical conditions, most NSAIDs are avoided, especially in the third trimester. They can lead to premature closure of the ductus arteriosus (a vital blood vessel in the fetus), increased risk of miscarriage, and other complications like reduced amniotic fluid levels.
   2. Opioids – e.g., Codeine, Oxycodone, Hydrocodone: These are generally avoided, especially in the first and third trimesters, due to risks of dependence, withdrawal symptoms in the newborn (neonatal abstinence syndrome), and potential developmental issues. They may be used in certain controlled circumstances and under strict medical supervision.
   3. COX-2 Inhibitors – e.g., Celecoxib: These drugs, similar to NSAIDs, can affect the fetal cardiovascular system and are typically avoided during pregnancy.
3. Antibiotics
   1. Tetracyclines (e.g., doxycycline, minocycline): These antibiotics can affect bone growth and tooth coloration in the fetus. They are known to be deposited in bones and teeth, leading to discoloration and potential defects.
   2. Fluoroquinolones (e.g., ciprofloxacin, levofloxacin): These can cause cartilage damage. There’s also a concern about potential effects on the musculoskeletal system of the developing fetus.
   3. Trimethoprim: Especially in the first trimester, it’s avoided due to the risk of folate antagonism, which can lead to neural tube defects.
   4. Sulfonamides (e.g., sulfamethoxazole): in the first trimester, avoided due to the risk of folate antagonism, which can lead to neural tube defects. During late pregnancy, they may increase the risk of jaundice and kernicterus (a type of brain damage) in newborns.
   5. Aminoglycosides (e.g., gentamicin, tobramycin): They can be toxic to the ears (ototoxicity) of the fetus, potentially leading to hearing loss.
4. Anti-hypertensives
   1. ACE Inhibitors (e.g., Enalapril, Lisinopril): These drugs are associated with a high risk of congenital malformations, particularly when used in the second and third trimesters. They can cause kidney problems in the fetus, reduced amniotic fluid, and other developmental issues.
   2. Angiotensin II Receptor Blockers (ARBs) (e.g., Losartan, Valsartan): Similar to ACE inhibitors, ARBs are avoided due to the risk of fetal harm, particularly in the later stages of pregnancy.