Boosting supply is one of the most common topics in all breastfeeding groups, as mothers we tend to worry constantly over everything, and worrying about supply is no different.

Breastmilk supply is based on the basic principles of demand and supply, the more removal of milk from the breast, (demand), the more your body will produce (supply) to meet those demands. The most effective and safe way to maintain and increase supply is to empty the breast frequently and effectively, whether by feeding your baby on demand at the breast, or sticking to a schedule of 8 to 10 pumping sessions within 24 hours in the first few weeks of exclusively pumping.

Often new mothers are quickly prescribed medications by their baby’s pediatrician or by their gynae without first finding out if there is true low supply or what could be causing symptoms of low supply or slow weight gain. More often than not, it is due to something such as incorrect latch or a weak sucking reflex in baby, or unrealistic and unnecessary scheduling of feeds or sleep training, all of which are easily remedied without the need for galactagogues.

A lot of the times when a mother feels her supply is low it is due to perceived low supply, and not true low supply, as explained here and here.

If you feel your supply is low, it is best to consult with a breastfeeding expert such as a certified lactation consultant or La Leche League leader to address any underlying issues to help with supply.  

Stress, dehydration and exhaustion can all impact supply and on top of the underlying stressors of everyday mothering, the added worry can further impact supply issues, it is important to find balance and ask for help where needed, safe co-sleeping practices can help you achieve more sleep, keeping hydrated and making sure you eat a diet high in healthy fats like avocado, nuts and berries can help boost your energy levels, avoid high sugary foods and drinks or highly caffeinated drinks as they can spike your energy levels and leave you feeling even more drained once they wear off.
If you genuinely feel that medication is your only option, then it is important to discuss all side effects and information with your doctor.

Medications such as sulpirides (eglynol and esperide) are often prescribed off label as a lactation aide, but their primary use is for the treatment of schizophrenia and severe depressive disorders. If you are taking enough of a medication to “benefit” from the side effects then the medication is having an effect on your brain. Weaning from anti-physcotics should be done slowly and under the guidance of a certified medical practitioner.

Other medications such as Domperidone (Motilium) can have adverse reactions with mothers who suffer underlying heart conditions, but according to Dr Jack Newman, this option is still safer than other medications such a sulpirides.

Always consult with a certified lactation specialist such as a Le Leche League Leader or certified Lactation Consultant (IBCLC or SACLC) with regards to supply issues, unfortunately not all medical practitioners specialize in breastfeeding and have a very limited and outdated knowledge on breastmilk and breastmilk production. It is important to rule out any easily resolved issues before leaning towards medical or herbal medicines for supply issues.

If you are looking for trusted breastfeeding support, check out this link for names of certified lactation consultants and La Leche League leaders near you.
Herbal supplements, although natural, are not always safe or free from side effects, you should discuss taking any supplement with a knowledgeable practitioner. Always be aware of any changes in behaviour and bowel movements with baby when starting supplements. Most galactagogues are anecdotal and offer only temporary increases in supply.

Some mothers or babies can be allergic to herbal supplements such as fenugreek as explained in this article.
Jungle juice is frequently recommended for use to boost breastmilk supply, however there is nothing in jungle juice that is considered a galactagogue.

Jungle juice is simply a very sugary hydration solution, and as far as hydration solutions go, there are several healthier and more effective alternatives to this high sugar, high calorie drink.

The ingredients in jungle juice can cause thrush due to the very high sugar content, can lead to weight gain and is extremely dangerous for mothers who are insulin resistant or diabetic.
Jungle juice does not increase supply, it increases hydration, which can aide in lactation. Some healthier alternatives to jungle juice are: plain water, homemade fruit infused water and coconut water.

It is important to understand that there are no magic pills or foods that will increase your milk supply if breastmilk is not being removed effectively and frequently from the breast.

One of the most effective and safest manners in which to increase and maintain supply is to pump often, feed on demand if nursing or using techniques such as power pumping.