The following information is for people with Diabetes:
People with Diabetics in their family need special instructions. If you are a Diabetic or harbor the Type-2 gene within your genetic code then pumping will be much more difficult and you will have to be extra careful. Diabetes destroys one's vascular system over time. The elevated blood sugar causes nicks in your vessel walls that in time lead to cardiovascular diseases of all sorts (hypertension, stroke, heart attack). People with Diabetes have poor feet and hand circulation and... you guessed it, POOR GENITAL CIRCULATION. Most of the Viagra, Cialis and Levitra sold in the world is consumed by men with either Diabetes or Type-2 Diabetes.
Pumping with Diabetes is soooo much more risky than people who do not have the disease. Diabetic pumpers have an increased risk of damaging the capillaries of the inner foreskin as well as an increased risk of water blisters... most will notice that the skin of the penis damages much more quickly also. Not only are Diabetics at an increased risk of damaging their blood vessels and tissue, they are slower to heal as well.
Do you have a grandparent with Diabetes? If you do, then you probably harbor the Type-2 gene. If you have a parent, Aunt or Uncle who is Diabetic then you DEFINITELY have the gene. There are many factors which can accelerate the instance of full blown Diabetes in Type-2 people and on the other hand there are other factors that can slow it's development. Being overweight is a death sentence for those with the Type-2 gene, it is basically the path to Diabetes for them. So, those who have a family history of Diabetes and are overweight... pumping can provide significant risks to the health of one's penis.
What to do?
Well, patience and an unenthusiastic approach are both needed. Patience you say? You will need to go much slower and pump lighter and less frequently. You will have to watch that gauge like a hawk and never pump above 6 inches of mercury. You will have to take breaks more frequently and apply cold to the head of the penis (for around 30 seconds)to prevent water blisters from forming. You will need a medicated wonder ointment like Carmex to apply to the inner foreskin to keep it moisturized and protected.
Dampening down the enthusiasm is necessary to not overpump, once you see your cock growing and get used to a bit more size, you will need to gather all of your forces to chill out and not go for even more size too fast. Once you pack the tube... go ahead and get out, staying in the tube too long after you've packed it increases the chances of a water blister forming by nearly 70%, so watch it. If you do get a blister, pop that mofo with a sterilized needle (alcohol is fine, get the 90%) and apply cold and then Carmex on the site of the blister. Check it every hour or so and re-pop it with the needle and repeat the cold and Carmex. You can also crush up an aspirin and apply the powder to the blister and then cover it with Carmex to seal it. Dryness and the friction from rubbing against fabric is horrible for blisters, so get some tight briefs and pack up your cock with it's moisturizer on. You will get moisturizer all over your briefs, but your cock will stay hydrated and healthy.
If you are a Diabetic pumper, PM me and I can give you an extra tip that can save your blood vessels from damage.