I would advise not to use Aloe Vera gel for treating pimples. For mild pimples (low-grade Acne Vulgaris), starting treatment with a Tretinoin 0.025% Ointment is a good option. This ointment also has anti-wrinkle and anti-ageing effects.
Next Steps
Consult a General Physician/Dermatologist for further workup.
Health Tips
This Ointment can make your face dry, so use adequate moisturizers.